%0 Conference Paper %B 81st Annual Conference, Savannah, Georgia %D 2022 %T 3779. Determining the Center of Gravity of the Electric No Emissions Low Drag Airframe (NELDA) %A Christl K. Haley %K 03. Center Of Gravity %K 10. Weight Engineering - Aircraft Design %K Student Papers %X

Although climate change has become an impending issue for all of humanity, it has brought nations together to design and create a variety of systems that leave little to no carbon footprint. The No Emission Low Drag Airframe (NELDA) is a unique electric aircraft design which aims to join this world-wide mission. The author (the airframe design lead) and her senior design team from the University of Colorado Boulder spent the fall semester of 2021 designing this commuter aircraft. NELDA can fly 6 passengers at a cruise altitude of 12,000 ft MSL, at a cruise speed of 150 knots for 1.5 hours with a 30-minute reserve, making this a perfect aircraft for short, direct flights. The characteristics for this aircraft aim to be certified under Federal Aviation Regulation (FAR) 23 to ensure the safety of every passenger. Multiple trade studies were conducted to determine the design choices that make up this innovative aircraft. These studies resulted in an aft-mid-mounted wing, a canard, fixed tricycle landing gear, butterfly doors, and a pusher-propeller powertrain configuration. The specific energy, density, volume, and weight of the electric powertrain were estimated using a 5-year prediction for solid-state batteries. Since these batteries do not exist today, it was very challenging to accurately model and place the power system. The range and endurance of NELDA were used to determine the volume, number, and weight of the batteries. The safety of passengers, size of the batteries, and functionality of each battery were all considered while determining where and how to place the batteries among the other major components of NELDA. Additionally, it was critical to strategically place each of the components to achieve an acceptable static margin of 10%, as well as predictable dynamic and static flight characteristics. The designers of NELDA believe that their successful commuter electric airplane design will be part of the beginning of new, improved, clean aerial transportation.

%B 81st Annual Conference, Savannah, Georgia %I Society of Allied Weight Engineers, Inc. %C Savannah, Georgia %P 27 %G eng %U https://www.sawe.org/papers/3779/buy %0 Conference Paper %B 2021 SAWE Tech Fair %D 2021 %T 3768. Mass Properties Reporting %A Ma, Yiyuan %A Yan, Jin %A Elham, Ali %K 10. Weight Engineering - Aircraft Design %K 11. Weight Engineering - Aircraft Estimation %K Student Papers %X

The Ultra-High Aspect Ratio Wing (UHARW) concept can improve the aircraft's aerodynamic efficiency and reduce fuel consumption. The Twin-Fuselage (TF) configuration is one of the most promising concepts for the UHARW design to reduce the wing bending moments and shear forces. This paper presents the development of a semi-empirical method for the weight estimation of TF aircraft in the initial sizing stage. A physics-based wing weight estimation method is improved for higher aerodynamic analysis fidelity and composite materials, which is used in the design of experiments and the results are applied for regression analysis to establish a semi-empirical method. Eventually, the established semi- empirical weight estimation method is integrated into a TF aircraft conceptual design and performance analysis framework, and a mid-range TF aircraft and a long-range TF aircraft are designed and sized to illustrate its application and efficiency in rapidly estimating the TF aircraft weight breakdown.

 

%B 2021 SAWE Tech Fair %I Society of Allied Weight Engineers, Inc. %C Virtual Conference %P 28 %8 11/2021 %U https://www.sawe.org/papers/3768/buy %L 10, 11 %1

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%2 15 %3 20 %4 SAWE3730 %0 Conference Paper %B 2020 SAWE Tech Fair %D 2020 %T 3734. Dynamic Computer Simulation of Aircraft Buoyancy %A Stubbers, Peter %K 10. Weight Engineering - Aircraft Design %X

I

Aircraft buoyancy is an important consideration in safe aircraft design. FAR 25.801 requires that in the event of emergency water landings, an aircraft must float long enough for passengers and crew to escape and board life rafts.

Current methods do not include any analysis of stability, and each solution must be developed for an exclusive aircraft and configuration.

To demonstrate compliance with this regulation, this study describes an improved method using a dynamic computer simulation developed with Simcenter Amesim that models the aircraft's position, orientation, weight, center of gravity, and center of buoyancy during a water landing. Internal geometry is modeled at points where water can leak into the plane as air tanks with variable flow rate orifices, allowing a simulation to show the change in buoyancy characteristics as water leaks into the aircraft and predict how much time passengers and crew will have for safe egress.

This method improves upon past methods, allowing for a wider range of testing. Physical validation is beyond the scope of this study.

 

%B 2020 SAWE Tech Fair %I Society of Allied Weight Engineers, Inc. %C Virtual Conference %P 97 %8 07/2020 %U https://www.sawe.org/papers/3734/buy %L 10 %1

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%2 15 %3 20 %4 SAWE3730 %0 Conference Paper %B 2020 SAWE Tech Fair %D 2020 %T 3739. Rotorcraft Mass Assessment in an Integrated Design Framework %A Schwinn, Dominik B. %A Peter Weiand %K 10. Weight Engineering - Aircraft Design %K 21. Weight Engineering - Statistical Studies %K 24. Weight Engineering - System Design %X

Mass estimation is an essential discipline in the design process of aeronautical vehicles. The maximum take-off mass determines most other design parameters and should therefore be estimated sufficiently precise from the beginning. In the conceptual design phase fast analyses are required in order to allow trade-off studies. In general, this phase is dominated by the use of analytical and statistical methods. At the end of this design stage, a basic external layout has been elaborated and basic design parameters have been determined.

During the subsequent preliminary design stage, physics based higher fidelity methods are applied to further elaborate the design and to establish an internal configuration. The constantly increasing computational power allows comparably fast analyses in this design stage that may alter the configuration established in the conceptual design stage.

Particular challenges in this design approach arise with unconventional configurations, such as compound rotorcraft, or with different propulsion systems to be integrated, for instance electric or hybrid systems, because of a lack of sufficient statistical data.

The German Aerospace Center (DLR) has established the integrated design environment IRIS (Integrated Rotorcraft Initial Sizing) to allow an assessment of virtual rotorcraft configurations. It covers the conceptual and parts of the preliminary design stage and uses the data model CPACS (Common Parametric Aircraft Configuration Schema) for the parametric rotorcraft description.

Component masses in IRIS are estimated using various statistical methods during the conceptual design stage. Finite Element (FE) methods are applied in the preliminary design phase to allow a more precise estimation of the structural mass which may influence the maximum take-off mass and therefore the performance characteristics calculated in the conceptual design stage.

This paper introduces the design environment IRIS, and in particular the PANDORA framework (Parametric Numerical Design and Optimization Routines for Aircraft) which is used for the statistical estimation of the rotorcraft component masses and the structural sizing process to determine the fuselage mass.

 

%B 2020 SAWE Tech Fair %I Society of Allied Weight Engineers, Inc. %C Virtual Conference %P 15 %8 07/2020 %U https://www.sawe.org/papers/3739/buy %L 10, 21. 24 %1

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%2 15 %3 20 %4 SAWE3730 %0 Conference Paper %B 2020 SAWE Tech Fair %D 2020 %T 3760. Design for Positive Static Margin for a Radio-Controlled Box-Wing Aircraft %A Bellerjeau, Charlotte %K 10. Weight Engineering - Aircraft Design %K 34. Advanced Design %K Student Papers %X

This paper will detail the aerodynamic design of a small unmanned box-wing aircraft to facilitate the study of turbulence by Dr. Brian Argrow at the CU Boulder. A design with no fuselage was necessary for the data collection, which presented a longitudinal stability challenge. The key to eventually achieving a stable design was weight placement for positive static margin. This paper will include the design process used to confront these issues. The initial choices of stagger, gap, decalage, and relative sweep are made using a simple model leveraging previous box-wing research. These, as well as the airfoil selection, are then investigated further using Athena Vortex Lattice (AVL) to analyze lift, drag, and stability. The final airframe design has a gap and stagger of 1 chord length, decalage of 5 degrees, and relative sweep of 30 degrees. A cambered NACA 6412 airfoil on the top wing and a reflexed NACA23112 airfoil on the bottom wing are selected, which combine to induce a positive pitching moment and aid in longitudinal stability. The resulting box-wing aircraft was flight tested successfully and will serve as an ideal platform for research at CU Boulder.

 

%B 2020 SAWE Tech Fair %I Society of Allied Weight Engineers, Inc. %C Virtual Conference %P 12 %8 07/2020 %U https://www.sawe.org/papers/3760/buy %L 10, 34, Student Papers %1

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%2 15 %3 20 %4 SAWE3730 %0 Conference Paper %B 78th Annual Conference, Norfolk, VA %D 2019 %T 3714. Weight and Design Data for World War II – Era United States Military Aircraft %A Dudley M Cate %K 10. Weight Engineering - Aircraft Design %K 30. Miscellaneous %X

Sources of weight data for World War II-era U.S. military aircraft recently were located in the U.S. Federal Archives. The data is to the level of detail found in a short group weight statement. To the author’s knowledge, the weight data has not heretofore been publicly available. It was felt to be worthwhile to electronically tabulate the data and then make it available via the SAWE.

The paper begins with an introduction that identifies the groundrules and constraints associated with the material in the paper. The rest of the paper presents both weights and weight fractions for the weight empty groups and the useful load items for a wide range of aircraft. The aircraft are arranged by type (fighter, bomber, etc.), military service (Army or Navy), and, in general, chronologically by model (P-40, P-39, P-47, etc.). Also included for each aircraft are the weights of alternate fuel and payload items.  For most of the aircraft, the weight empty and gross weight obtained from the archived data are validated by comparing them with weights found in open sources. Values for some of the weight-related design attributes for each aircraft are provided. Accompanying this data is a brief discussion of weight-related considerations for each aircraft.

The large number of aircraft for which data are included presents a clear picture of how group and total weights and weight fractions changed with time (e.g., from the pre-war Boeing P-26 to the post-war Lockheed P-80). The data also permit comparison of the differences between, for example, radial-engined and in-line-engined fighters, between Army and Navy fighters, between Navy dive bombers and torpedo bombers, and between biplane and monoplane trainers, to mention just a few of the possibilities.

%B 78th Annual Conference, Norfolk, VA %I Society of Allied Weight Engineers, Inc. %C Norfolk, Virginia %P 39 %8 05/2019 %U https://www.sawe.org/papers/3714/buy %L 10, 30 %1 Non-Member Price: $20.00; Member Price: $15.00 %2 15 %3 20 %4 SAWE3714 %0 Conference Paper %B 78th Annual Conference, Norfolk, VA %D 2019 %T 3729. Application of SAWE Course “Developing Basic Parametric Methods” to Nacelle Weight Estimating %A Fisher, Doug %K 10. Weight Engineering - Aircraft Design %K 11. Weight Engineering - Aircraft Estimation %K 21. Weight Engineering - Statistical Studies %X

This paper details how the learning contained in SAWE course “Developing Basic Parametric Methods” was applied at Collins Aerospace for estimating nacelle weights of new commercial and business jet aircraft. Collins has decades of experience developing nacelles and a large database of historical weight data, but has not effectively leveraged that data into better weight estimating tools. Learning from this course was applied to develop improved methods of estimating the weight of nacelles for new product proposals. This has allowed us to not only provide better weight estimates but also better understand the limits of our data and estimating methods.

%B 78th Annual Conference, Norfolk, VA %I Society of Allied Weight Engineers, Inc. %C Norfolk, Virginia %P 17 %8 05/2019 %U https://www.sawe.org/papers/3729/buy %L 10, 11, 21 %1 Non-Member Price: $20.00; Member Price: $15.00 %2 15 %3 20 %4 SAWE3729 %0 Conference Paper %B 76th Annual Conference, Montreal, Canada %D 2017 %T 3690. Weight Optimization of Environmental Control System of Corporate Jets %A Mitry, Ragaa %K 10. Weight Engineering - Aircraft Design %K 24. Weight Engineering - System Design %X

The environmental control system (ECS) is an essential system in the aircraft; it provides air supply, thermal, humidity, ventilation, and cabin pressurization for the crew and passengers. It is also used for engine anti-ice, main door sealing, avionic cooling, and smoke detection.
ECS is sized to meet the aircraft mission. It is the highest power-consuming system on the aircraft.

The basic designs of the ECS used on most aircraft, in both corporate jets and commercial airliners, are remarkably similar. In simplified terms, air is first compressed to high pressure and temperature in the engine compressors, cooled in a precooler before entering the fuselage then conditioned by an air cycle machine (ACM) where excess moisture is removed and the temperature necessary for heating or cooling the airplane is established. The conditioned air is then delivered to the cabin and cockpit through the duct distribution system to maintain a comfortable environment.

To optimize the system from the weight point of view, a complete analysis of each component must be considered and evaluated. The weight of the ECS is driven by the bleed air pressure and temperature which determines the size of the precooler (Reference SAWE Paper # 3648; Engine Integration to Aircraft of Corporate Jets).The thermal heating and cooling load will determine the extracted bleed airflow quantity, which in turn, will impact the ACM size and weight.

Most of the ECS components are designed and provided by suppliers but the air distribution ducts are laid out by the airframers and that deserves more attention. The adverse effect of paying little attention to duct optimization is a weight penalty and cost increase. The ducts’ layout, size, and shape can lead to increased cabin’s noise which is usually treated by additional sound attenuation materials on the account of weight, cost, and maintainability. The duct noise can also lead to other problems such as vibration and passenger’s discomfort.
This paper will focus on addressing the air distribution duct design and layout as related to weight optimization.

%B 76th Annual Conference, Montreal, Canada %I Society of Allied Weight Engineers, Inc. %C Montreal, Canada %P 20 %8 05/2017 %U https://www.sawe.org/papers/3690/buy %1 Non-Member Price: $20.00; Member Price: $15.00 Members: First 10 product downloads are Free. %2 15 %3 20 %4 SAWE3690 %0 Conference Paper %B 75th Annual Conference, Denver, Colorado %D 2016 %T 3655. Weight and Structural Optimization in Aircraft Design %A Alves, William %A da Silva, Juliana %K 10. Weight Engineering - Aircraft Design %K 22. Weight Engineering - Structural Design %K 28. Weight Reduction - Processes %K 34. Advanced Design %X Given the competitiveness of the current market, there is a growing movement in the sense of increase the efficiency of aeronautical product in an appropriate life cycle for airliners needs. In the context of aeronautical structures, the challenge is to increase structural efficiency within the number of cycles required for life in service, meeting reliability requirements and loads, without losing sight of the dynamic performance of structural components. This article is intended to present the main structural optimization techniques and estimating the gains made at various stages of development of the aircraft design. %B 75th Annual Conference, Denver, Colorado %I Society of Allied Weight Engineers, Inc. %C Denver, Colorado %P 30 %8 05/2016 %U https://www.sawe.org/papers/3655/buy %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE3655 %0 Conference Paper %B 75th Annual Conference, Denver, Colorado %D 2016 %T 3660. Development of a Conceptual Flight Vehicle Design Weight Estimation Method Library %A Walker, Andy %K 10. Weight Engineering - Aircraft Design %K 11. Weight Engineering - Aircraft Estimation %K Mike Hackney Best Paper Award %X

The state of the art in estimating the volumetric size and mass of flight vehicles is held today by an elite group of engineers in the Aerospace Conceptual Design Industry. This is not a skill readily accessible or taught in academia. To estimate flight vehicle mass properties, many aerospace engineering students are encouraged to read the latest design textbooks, learn how to use a few basic statistical equations, and plunge into the details of parametric mass properties analysis. Specifications for and a prototype of a standardized engineering “tool-box” of conceptual and preliminary design weight estimation methods were developed to manage the growing and ever-changing body of weight estimation knowledge. This also bridges the gap in Mass Properties education for aerospace engineering students. The Weight Method Library will also be used as a living document for use by future aerospace students. This “tool-box” consists of a weight estimation method bibliography containing unclassified, open -source literature for conceptual and preliminary flight vehicle design phases. Transport aircraft validation cases have been applied to each entry in the AVD Weight Method Library in order to provide a sense of context and applicability to each method. The weight methodology validation results indicate consensus and agreement of the individual methods. This generic specification of a method library will be applicable for use by other disciplines within the AVD Lab, Post- Graduate design labs, or engineering design professionals.

%B 75th Annual Conference, Denver, Colorado %I Society of Allied Weight Engineers, Inc. %C Denver, Colorado %P 171 %8 05/2016 %U https://www.sawe.org/papers/3660/buy %1 Non-Member Price: $85.50; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 85.5 %4 SAWE3660 %0 Conference Paper %B 75th Annual Conference, Denver, Colorado %D 2016 %T 3662. Minimizing Mass of a Spacecraft Structure %A Burkey, Larry %A Cervantes, Jorge %A Gillis, Lewis %A Graser, Evan %A Howard, Megan %A Iskra, Andrei %A Maurer, Taylor %A Peterson, Davis %A Williams, Margaret %K 10. Weight Engineering - Aircraft Design %K Student Papers %X The commercialization of the International Space Station (ISS) has created the opportunity for a wider variety of minisatellites to be launched to and deployed from the ISS. By utilizing ISS resupply vehicles, these spacecraft are launched to the ISS in a soft stowed configuration and undergo much lower vibration loads than in a typical launch configuration. The FeatherCraft spacecraft is designed to fully exploit this opportunity by offering a 100-kilogram spacecraft with 45 kilograms available for science payload use. This leaves only 5 kilograms for the required side panels and internal mounting surfaces that constitute the spacecraft structure. Most spacecraft structures represent approximately 20% of the total spacecraft mass, so the reduction of the structure to 5% of the total mass requires innovative mass-relieving techniques. To solve this problem, undergraduate aerospace engineering students at the University of Colorado at Boulder created FISH, the FeatherCraft Integrated Structural Housing, which achieves the required mass reduction and integrates with other spacecraft components. This unprecedented mass reduction is accomplished by utilizing composite materials, minimizing structure area and thickness, and finally using adhesives for attachments on nearly every interface. Critical components of the structure design were preliminarily verified through bending tests, Finite Element Analysis (FEA), and adhesive tests. A complete structural full-scale model will be tested under the expected vibrational loads and acceleration measurements will be taken to verify expected performance. The success of this novel design creates a new cost-effective approach to Low-Earth-orbiting missions. %B 75th Annual Conference, Denver, Colorado %I Society of Allied Weight Engineers, Inc. %C Denver, Colorado %P 26 %8 05/2016 %U https://www.sawe.org/papers/3662/buy %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE3662 %0 Conference Paper %B 74th Annual Conference, Alexandria, Virginia %D 2015 %T 3648. Engine Integration to Aircraft of Corporate Jets %A Mitry, Ragaa %K 10. Weight Engineering - Aircraft Design %X Engine selection is a crucial part of the preliminary design of the aircraft development to meet the aircraft mission. While significant efforts are focused on the engine characteristics, it is critical not to ignore the impact of the engine integration to the aircraft. Before making the final selection, it is important to evaluate the impact of the individual engine components on the overall aircraft weight and center of gravity (CG) beyond the engine itself. The engine’s main components; fan, compressor, combustor, turbine and nozzle; as developed by different engine manufacturers; typically share a similar architecture from engine to engine. By analyzing the impact of each component on several engine manufacturer proposals on various programs, it was observed that the compressor and the fan have significant impact on the aircraft integration. The compressor design has a large influence on the total engine performance as well as aircraft structure and systems. This paper focuses on the engine integration to the aircraft and discusses the importance of evaluating the bleed air extracted at various stages of the compressor where manufacturer’s provisions for low and high pressure bleed are commonly offered. In most cases, the manufacturers propose an engine solution based on existing design or developed from an existing design. The engine bleed air pressure and temperature impact the Environmental Control System (ECS) and the Cabin Pressurization Control System (CPCS), the higher the pressure and temperature of the extracted air, the bigger and heavier the associated precooler, ducts, and valves; which in turn increase the overall weight of the aircraft. Moreover, for aft engine mounted aircraft; the additional weight will shift the CG further aft. Weight estimates, based on different manufacturers’ design of compressor bleed air extraction stages and fan pressure, should be incorporated in the suppliers’ scorecard to ensure that the weight impact driven by the engine integration on the ECS, CPCS, and the airframe structure is within the weight limit, and minimized. If the weight projection exceeds the preliminary estimated weight, it should be immediately acknowledged as a potential problem to avoid a significant weight penalty and a compromised performance later in the program. %B 74th Annual Conference, Alexandria, Virginia %I Society of Allied Weight Engineers, Inc. %C Alexandria, Virginia %P 17 %8 05/2015 %U https://www.sawe.org/papers/3648/buy %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE3648 %0 Conference Paper %B 73rd Annual Conference, Long Beach, California %D 2014 %T 3615. Application Of A Flexible Wing Modeling And Physical Mass Estimation System For Early Aircraft Design Stages %A Dorbath, Felix %K 10. Weight Engineering - Aircraft Design %K 23. Weight Engineering - Structural Estimation %X State-of-the-art models in preliminary wing design apply physics-based methods for primary structures while using empirical correlations for secondary structures. Using those methods, a detailed optimization such as e.g. rear spar positions or flap size is only possible within a limited design space. Novel structural concepts such as multi-spar flap layouts or the introduction of composite materials cannot be analyzed using statistical methods and require extended higher level structural modeling. Therefore, a flexible wing modeling and physical mass estimation system for early aircraft design stages is developed — the WINGmass system. The core of the interdisciplinary tool chain is a central model generator that automatically generates all analysis models from the DLR aircraft data format CPACS (Common Parametric Aircraft Configuration Scheme). For the automatic model generation, a large amount of engineering rules are implemented in the model generator, to reduce the amount of required input parameters and therefore to relieve the aircraft designer. Besides the multi-model generator, the tool chain consist of a structural finite element model (incl. wing primary structures, flaps, flap tracks, ailerons, engine pylon and landing gear), a structural sizing algorithm and loads models for aerodynamic, fuel, landing gear and engine loads. The wing mass estimation system is calibrated against real mass values of the wing primary structures and the trailing edge devices of the Airbus A320 and A340-200. The results of the calibrated tool chain are compared to the masses of the primary structures of the B747-100 and the aluminum baseline version of the MD-90-40X. The calibration factors for composite primary structures are derived from the composite version of the MD-90-40X. Finally, the benefits of the extended physics-based modeling and the application of the WINGmass system in an interdisciplinary aircraft design environment are shown in an aircraft design study. The objective of this study is to compute the optimal wing shape in terms of mission fuel as a function of the take-off field length. Therefore, a parameter variation of the wing and flap geometry is performed, the engine scaled correspondingly and the mission fuel evaluated. %B 73rd Annual Conference, Long Beach, California %I Society of Allied Weight Engineers, Inc. %C Long Beach, California %P 23 %8 05/2014 %U https://www.sawe.org/papers/3615/buy %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE3615 %0 Conference Paper %B 72nd Annual Conference, St. Louis, Missouri %D 2013 %T 3594. Refined Preliminary Weight Estimation Method for Multidisciplinary Shape Optimization of Lifting Surfaces %A Elham, Ali %A van Tooren, Michel J. L. %K 10. Weight Engineering - Aircraft Design %X A strategic focus area for NASA is to pursue the development of technologies which support exploration in space beyond the current inhabited region of low earth orbit. An unresolved issue for crewed deep space exploration involves limiting crew radiation exposure to below acceptable levels, considering both solar particle events and galactic cosmic ray contributions to dosage. Galactic cosmic ray mitigation is not addressed in this paper, but by addressing credible, easily implemented, and mass efficient solutions for the possibility of solar particle events, additional margin is provided that can be used for cosmic ray dose accumulation. As a result, NASA’s Advanced Engineering Systems project office initiated this Radiation Storm Shelter design activity. This paper reports on the first year results of an expected 3 year Storm Shelter study effort which will mature concepts and operational scenarios that protect exploration astronauts from solar particle radiation events. Large trade space definition, candidate concept ranking, and a planned demonstration comprised the majority of FY12 activities. A system key performance parameter is minimization of the required increase in mass needed to provide a safe environment. Total system mass along with operational assessments and other defined protection system metrics provide the guiding metrics to proceed with concept developments. After a downselect to four primary methods, the concepts were analyzed for dosage severity and the amount of shielding mass necessary to bring dosage to acceptable values. Besides analytical assessments, subscale models of several concepts and one full scale concept demonstrator were created. FY12 work terminated with a plan to demonstrate test articles of two selected approaches. The process of arriving at these selections and their current envisioned implementation are presented in this paper. %B 72nd Annual Conference, St. Louis, Missouri %I Society of Allied Weight Engineers, Inc. %C Saint Louis, Missouri %P 27 %8 05/2013 %U https://www.sawe.org/papers/3594/buy %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE3594 %0 Conference Paper %B 72nd Annual Conference, St. Louis, Missouri %D 2013 %T 3606. Design Considerations Of Flight Control Systems In High Performance General Aviation Aircraft %A McCloud, Darrin %K 10. Weight Engineering - Aircraft Design %X The current trend for new business jet designs is for larger, faster aircraft at a minimum price point. Almost all of the slower entry-level planes use manual flight control systems while all of the large business jets are required to use powered flight control systems. What happens in the gray area in- between, when a manual flight control system is preferred but the size and speed of the aircraft make it difficult to design? Many design choices will impact the size, weight and effectiveness of the flight control system and the difference in these choices will determine whether the overall aircraft design is a success. Incorrect choices can lead to costly redesign, poor performance or flutter concerns. This paper will concentrate on design issues with traditionally controlled, manually powered jet aircraft and several design factors to be aware of during the early phase of aircraft development. %B 72nd Annual Conference, St. Louis, Missouri %I Society of Allied Weight Engineers, Inc. %C Saint Louis, Missouri %P 20 %8 05/2013 %U https://www.sawe.org/papers/3606/buy %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE3606 %0 Conference Paper %B 71st Annual Conference, Bad Gögging, Germany %D 2012 %T 3547. Implementation of a Tool Chain for Extended Physics-Based Wing Mass Estimation in Early Design Stages %A Dorbath, Felix %A Nagel, Björn %A Gollnick, Volker %K 10. Weight Engineering - Aircraft Design %K 23. Weight Engineering - Structural Estimation %K Mike Hackney Best Paper Award %X

The state-of-the-art methods in preliminary wing design are using models employing physics-based methods for primary structures while using empirical correlations for secondary structures. Using those methods, detailed optimization as e.g. rear spar positions or flap size is only possible within a limited design space. Novel structural concepts such as multi-spar flap layouts or the introduction of composite materials cannot be analyzed using statistical methods and require extended higher level structural modeling. Therefore an interdisciplinary tool chain is developed for extended physics-based wing mass estimation. The tool chain consists of the following components: one central model generator, a structural finite element model, a structural sizing algorithm and loads models for aerodynamic, fuel, landing gear and engine loads. The structural finite element wing model consists of the following main parts: wing box, fixed trailing edge devices, movable trailing edge devices, spoilers, landing gears and engine pylons. The model generator is able to create several different kinds of track kinematics, covering most of the track types used in state-of-the-art aircrafts. To make the complexity of the model generation process feasible for one aircraft designer, a knowledge based approach is chosen. Therefore the central model generator requires a minimum set of easy-to- understand input parameters. This enables the aircraft designer to focus on the design and not on calculating input parameters. To include the tool chain in a wider multidisciplinary aircraft design environment, the aircraft parameterization CPACS (Common Parametric Aircraft Configuration Scheme) is used as central data model for input and output. The developed tool chain is implemented as flexible as possible to enable the designer to analyze also novel structural concepts or wing configurations. On wing configurational level, the tool chain can handle most types of different wing concepts, such as e.g. blended wing bodies, strut-braced wings and box wings. On the structural concepts side, the tool chain is able to handle various different rib and spar layouts and different materials (incl. composites).

%B 71st Annual Conference, Bad Gögging, Germany %I Society of Allied Weight Engineers, Inc. %C Bad Gögging, Germany %P 21 %8 05/2012 %U https://www.sawe.org/papers/3547/buy %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE3547 %0 Conference Paper %B 71st Annual Conference, Bad Gögging, Germany %D 2012 %T 3571. An Advanced Quasi-Analytical Weight Estimation Method for Airplane Lifting Surfaces %A Elham, Ali %A La Rocca, Gianfranco %A van Tooren, Michel J. L. %K 10. Weight Engineering - Aircraft Design %X This paper describes a novel weight prediction method for aircraft lifting surfaces, which is able to combine the typical accuracy of finite element (FE) based weight estimation methods, with the computational speed of the classical semi empirical (class II) methods used in conceptual design. In the proposed method the use of semi empirical equations is limited to the estimation of the secondary weights of wing and tailplanes. The weight prediction of the primary structure is achieved by means of an advanced analytical method, which makes use of the actual geometry of aerodynamic surfaces and structural layout, and the computed lift forces distribution. In particular, a set of mathematical equations has been derived to relate the required structural properties of the wing box to the specific shape of the used airfoils. These equations allow modelling the skin, the spar caps and the stringers of the upper and lower side of a given wing box into two equivalent flat panels, and then calculate their “effective distance”. This distance is indeed the factor that allows accounting for the effect of the given airfoil shape on the stress distribution in the panels, and enable a more accurate panel weight estimation than other methods proposed in literature. A realistic estimation of the spanwise lift distribution is another key factor to achieve accurate weight predictions. To this purpose, a commercial Vortex Lattice Method tool has been employed top derive the aerodynamic loads on the given lifting surface. The load cases are defined according to airworthiness regulations. The load relief effects provided by fuel and engine installation, as well as by the weight of the wing structure, are taken into account. The total weight of the given lifting surface is computed by adding the analytically calculated weight of upper and lower panels, spars and ribs, to the weight of the secondary structure (e.g., movables and fixed leading and trailing edge) and to the so called non-optimum weight group, which accounts for joints, cut-outs, attachments, etc. The last two contributions are estimated by means of semi empirical relations. The proposed lifting surface weight prediction method has been validated using data of various airplanes of different size, category and manufacturer. The computational time is dramatically lower than any finite element based sizing tool, while the achieved level of accuracy is comparable or even higher. Each weight prediction takes about 10 second on a standard PC. The average error on lifting surface total weight is less than 2%. Besides, the achieved combination of speed, accuracy and high level of design sensitivity (designer can assess the effect on weight of such parameters as airfoil shape, number, position and orientation of structural items, etc.) make the proposed tool suitable for multidisciplinary design optimization studies. %B 71st Annual Conference, Bad Gögging, Germany %I Society of Allied Weight Engineers, Inc. %C Bad Gögging, Germany %P 19 %8 05/2012 %U https://www.sawe.org/papers/3571/buy %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE3571 %0 Conference Paper %B 69th Annual Conference, Virginia Beach, Virginia %D 2010 %T 3509. Airframe Wingbox Preliminary Design and Weight Prediction %A AINSWORTH, JAMES %A COLLIER, CRAIG %A YARRINGTON, PHIL %A LUCKING, RYAN %A LOCKE, JAMES %K 10. Weight Engineering - Aircraft Design %X Currently Collier Research is evaluating the performance of many panel concepts for highly loaded, commercial transport wingbox structures. Software development is taking place as well as many new commercial contracts to further the effort. Simultaneously the HyperSizer® commercial software is being used world-wide on many commercial aircraft for the analysis and design sizing of composite and metallic aircraft structures. This paper focuses on trade studies performed on an aircraft wingbox structure. The wingbox is modeled after a commercial transport jet. The loads on the upper and lower wing skin surface are axially compression paired with high shear loading caused by wing twist. Weight trends are quantified considering all possible design possibilities in order to determine the most structurally efficient combination of composite layups and panel cross section dimensions to achieve the lightest weight. Included are results obtained with HyperSizer for Metallic Integral Blade and Bonded Zee Stiffened panel concepts as well as Composite Hat and Tee Stiffened panel concepts. The HyperSizer optimum designs have scored based on the weight maturity level (WML) of the panel design. The study shows the composite hat stiffened panel is the lightest concept for a wingbox structure and is 30% lighter than the lightest metallic design. %B 69th Annual Conference, Virginia Beach, Virginia %I Society of Allied Weight Engineers, Inc. %C Virginia Beach, Virginia %P 41 %8 05/2010 %U https://www.sawe.org/papers/3509/buy %L 3497 %1 Non-Member Price: $20.50; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20.5 %4 SAWE3509 %0 Conference Paper %B 68th Annual Conference, Wichita, Kansas %D 2009 %T 3467. Weight Analytics %A Higgins, Chuck %K 10. Weight Engineering - Aircraft Design %K 18. Weight Engineering - Spacecraft Design %K 22. Weight Engineering - Structural Design %X Weight Analytics addresses the gathering, analyzing, reporting and sharing of critical weight data and opening new horizons for the use of this knowledge within the design process. In this paper we will show the use of a cubical data base, allowing the user to look at an infinite number of dimensions of data quickly, easily and intuitively. Automation of the collection, storage, analysis and reporting on this disparate data has until now been challenging at the least. With the flexibility of the Rubix Cube, data is quickly and easily sliced and diced along any number of relationships thus “elevating data to knowledge.” %B 68th Annual Conference, Wichita, Kansas %C Wichita, Kansas %P 13 %8 5/16/2009 %U https://www.sawe.org/papers/3467/buy %9 10. Weight Engineering - Aircraft Design ; 18. Weight Engineering - Spacecraft Design; 22. Weight Engineering - Structural Design ; 24. System Design %M 3436 %L 10;18;22;24 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE3467 %0 Conference Paper %B 68th Annual Conference, Wichita, Kansas %D 2009 %T 3474. U.S. Fighter Aircraft Design, Weight And Performance Trends %A Dudley M Cate %K 10. Weight Engineering - Aircraft Design %K 21. Weight Engineering - Statistical Studies %X Weight engineers struggle with aircraft weight because it is so critically important to aircraft performance. Nowhere is this truer than for fighter aircraft. The U.S. has been operating fighters since 1917 and designing them since almost that long ago. This paper presents three sets of information for U.S. fighters: the first set consists of quantitative trends versus time for some top-level design, weight and performance parameters for U.S. fighters. The parameters addressed include ones commonly cited in aircraft histories (max speed, combat ceiling, initial climb rate) plus others such as weight empty fraction, fuel fraction, wing loading and power- and thrust-to-weight ratios. The second set of information is the results of searches for correlations between design parameters (e.g., wing loading) and performance parameters (e.g., climb rate). The third set consists of brief descriptions and assessments of the requirements, technologies, design, performance and operational suitability of each of the fifty-odd aircraft in the database. %B 68th Annual Conference, Wichita, Kansas %C Wichita, Kansas %P 95 %8 5/16/2009 %U https://www.sawe.org/papers/3474/buy %9 10. Weight Engineering - Aircraft Design; 11. Weight Engineering - Aircraft Design ; 21. Weight Engineering - Statistical Studies %M 3436 %L 10;11;21 %1 Non-Member Price: $47.50; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 47.5 %4 SAWE3474 %0 Conference Paper %B 67th Annual Conference, Seattle, Washington %D 2008 %T 3443. Alternate & Overhead Space Utilization In Long-Range Commercial Aircraft %A Druckman, Ralph D. %K 10. Weight Engineering - Aircraft Design %K 20. Weight Engineering - Specifications %X The Overhead Space Utilization (OSU) feature provides operators of Boeing airplanes with a range of options as rest space for flight and cabin crew with minimal impact to passenger cabin floor area (and seat count) while avoiding loss of revenue belly cargo capacity. As use of longer-range passenger airplanes on routes with flight durations requiring rest periods for flight crew and cabin attendants increases over time, the need for providing dedicated rest facilities and space for other main cabin passenger service functions has become much more important. The paper covers the evolution of pre-OSU and OSU concepts and provides insights into impacts of incorporating OSU. It is intended to provide a historical perspective, rather than functioning as a design guide. %B 67th Annual Conference, Seattle, Washington %C Seattle, Washington %P 34 %8 5/19/2008 %U https://www.sawe.org/papers/3443/buy %9 10. Weight Engineering - Aircraft Design, 20. Weight Engineering - Specifications %M 3443 %L 10; 20 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE3443 %0 Conference Paper %B 67th Annual Conference, Seattle, Washington %D 2008 %T 3446. Weight Control Responsibility, Authority, & Accountability %A LaSalle, Kenneth %K 10. Weight Engineering - Aircraft Design %K 28. Weight Reduction - Processes %X The roles and responsibilities of the Weight Control Engineer are clearly defined within the Weight Engineering Organization at the Boeing Company. Unfortunately, personnel in other disciplines within the Boeing Company often misunderstand our role - for a variety of reasons. Couple that reality with the trend toward outsourcing design and build responsibilities – whereby partnering companies furnish personnel from various disciplines. Supplying Weight Control Engineers can sometimes present a dilemma if that function does not exist within that company or if the company simply uses the weight engineer as a data recorder. Typically, partnering companies request individuals to perform this role with limited or no understanding. The burden of responsibility now belongs to Boeing to provide the necessary training. Additionally, the new employee has minimal exposure to the weight engineering function. These conditions mandate a philosophy of continual training to address the needs of many incoming personnel to Weight Engineering. This paper focuses on highlighting weight control attributes, addressing responsibilities, command of subject / authoritative effectiveness, and resultant accountability. These principles are intended to establish the solid foundation. Coupled with other SAWE papers pertaining to Weight Control, they will both aid and expedite the individual toward becoming effective in performing weight control. %B 67th Annual Conference, Seattle, Washington %C Seattle, Washington %P 26 %8 5/19/2008 %U https://www.sawe.org/papers/3446/buy %9 10. Weight Engineering - Aircraft Design; 28. Weight Reduction - Processes %M 3446 %L 10; 28 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE3446 %0 Conference Paper %B 67th Annual Conference, Seattle, Washington %D 2008 %T 3447. Developmental and Operational Considerations of The Boeing 747 Dreamlifter %A Kwaterski, Ryan %K 10. Weight Engineering - Aircraft Design %X The 747 Dreamlifter is a modified 747-400B passenger airplane that is simultaneously similar and largely different when compared to airplane it was created from. Large portions of the fuselage structure have been replaced and expanded to allow the Dreamlifter to carry Boeing 787 Dreamliner sections from around the world to Everett, Washington for final assembly. Along with the drastic fuselage modifications, the Dreamlifter has an 18,000 pound aluminum aft pressure bulkhead, a swing tail to allow loading of full size 787 parts and a special main deck cargo restraint system that only accepts unique payload support devices. These devices are referred to as Shipping Mechanical Equipment (SME) and were created solely to carry 787 parts onboard the Dreamlifter. In addition to the unique physical attributes of the airplane and the SMEs, some very special ground support equipment has also been designed for loading and unloading payload along with opening and closing the swing tail. Due to the unique aspects of the 747 Dreamlifter, special care and thought was required to develop procedures and manuals that offer operational flexibility and requirements for safe operation. This involved such items as a streamlined loading schedule, item specific loadable regions on the main deck and significant mass properties analysis. Development and Operational Considerations of the Boeing 747 Dreamlifter will touch almost every aspect of the Dreamlifter program from developmental and mass properties analysis to operational concerns and the airplane’s main mission to deliver full-size 787 components to final assembly. %B 67th Annual Conference, Seattle, Washington %C Seattle, Washington %P 29 %8 5/19/2008 %U https://www.sawe.org/papers/3447/buy %9 10. Weight Engineering - Aircraft Design %M 3447 %L 10 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE3447 %0 Conference Paper %B 67th Annual Conference, Seattle, Washington %D 2008 %T 3450. Boeing Optistruct Usage: Challenges of Implementation and the Emergence of a New Design Role %A Rucks, Greg %K 10. Weight Engineering - Aircraft Design %K 28. Weight Reduction - Processes %X Since 2004, Boeing has been using Altair’s Hypermesh and Optistruct pre- and post- FE processors as a means of reducing airplane weight. The process consists of two main optimization methodologies: 1) topology, which determines optimal load paths by iteratively re-orienting material within a given design space to maximize stiffness and 2) size & shape, finalizing the geometry by fine-tuning dimensions via gauge property modification or FEM morphing. Unorthodox part shapes and sizing combinations tend to result from these processes on parts ranging from Flight Control Actuators to Wing Primary Structure to Power Distribution Panels and Racks within the Electronics Bay. The optimization methods and processes currently in use by Boeing have resulted in average weight savings of 20% on 100+ parts, which usually also exhibit performance improvements with respect to stiffness, stress, and resonant frequency. While the design process is technically sound and has provided valuable results, several logistical challenges nevertheless arise during implementation. These challenges are systemic in nature and suggest a fundamental re-thinking of the design team structure and the nature of the interactions among its constituent parts. %B 67th Annual Conference, Seattle, Washington %C Seattle, Washington %P 14 %8 5/19/2008 %U https://www.sawe.org/papers/3450/buy %9 10. Weight Engineering - Aircraft Design; 28. Weight Reduction - Processes %M 3450 %L 10; 28 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE3450 %0 Conference Paper %B 66th Annual Conference, Madrid, Spain %D 2007 %T 3403. Topology Optimization on the Example of an Advanced Trainer Aircraft %A Anton, Hansjürgen %A Hörnlein, Herbert %K 10. Weight Engineering - Aircraft Design %K 24. Weight Engineering - System Design %X During the concept and definition phase of an aircraft, it is essential to define a structural concept, which provides the required strength and stiffness constraints of the airframe, subjected to a minimum of weight. The most efficient way of load transfer is a straight and undisturbed load path. However, the design space of the airframe is restricted by the outboard profile, which is defined by aerodynamics and flight mechanics and is also determined by the inboard profile, which is driven by systems installations. Howeve,r there are situations where a major load path cannot be continued, as is ideal. This presentation shows an example of how topology optimization can give one an idea to find an alternative load path. The example is given by a main wing attachment frame, which has the task of carrying the wing bending moment from one wing to the other. However, the air intake duct disturbs the assumed load path. There were some doubts by experienced airframe designers whether this air vehicle concept would work in an acceptable way in terms of mass and strength. The results of the topology optimization unveiled an alternative load path, which is subsequently interpretable by airframe engineers. This presentation also shows how the process goes from a given design to data for manufacturing. %B 66th Annual Conference, Madrid, Spain %I Society of Allied Weight Engineers %C Madrid, Spain %P 12 %8 5/28/2007 %G eng %U https://www.sawe.org/papers/3403/buy %9 10. Weight Engineering - Aircraft Design; 24. Weight Engineering - System Design %M 3403 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE3403 %0 Conference Paper %B 66th Annual Conference, Madrid, Spain %D 2007 %T 3408. On-Board Weight and Balance Application %A Vacher, Sylvain %K 10. Weight Engineering - Aircraft Design %X Everyday operation requires aircraft operators to have a load control process/system in order to ensure that aircraft weights and associated center of gravity remain within limits. For that purpose, the ground flight preparation usually relies on Departure Control Systems that generate, for each flight, the load and trim sheet for the attention of the captain. For some years now, Electronic Flight Bag solutions have been developed to bring added value to this general process by providing pilots with an additional portable weight and balance application. Using this application, pilots can further improve the current process by saving time-consuming requests for load sheet re computation to the ground. This paper focuses on this added value that an on-board weight and balance application can bring to manage everyday load control. The example of Airbus last generation application (developed for the A380) is used. %B 66th Annual Conference, Madrid, Spain %I Society of Allied Weight Engineers %C Madrid, Spain %P 20 %8 5/28/2007 %G eng %U https://www.sawe.org/papers/3408/buy %9 10. Weight Engineering - Aircraft Design %M 3408 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE3408 %0 Conference Paper %B 66th Annual Conference, Madrid, Spain %D 2007 %T 3410. Initial Sizing Optimization of Anisotropic Composite Panels with T-Shape Stiffeners %A Herencia, J. Enrique %A Weaver, Paul %A Friswell, Michael %K 10. Weight Engineering - Aircraft Design %K 23. Weight Engineering - Structural Estimation %X This paper provides an approach to perform initial sizing optimization of anisotropic composite panels with T-shape stiffeners. The method divides the optimization problem into two levels. At the first level, composite optimization is performed using Mathematical Programming (MP), where the skin and the stiffeners are modeled using lamination parameters accounting for their anisotropy. Skin and stiffener laminates are assumed to be symmetric, or mid-plane symmetric laminates with 0, 90, 45, or -45 degree ply angles. The stiffened panel is subjected to a combined loading under strength, buckling, and practical design constraints. Buckling constraints are computed using Closed Form (CF) solutions and energy methods (Rayleigh-Ritz). Conservatism is partially removed in the buckling analysis considering the skin-stiffener flange interaction and decreasing the effective width of the skin. Furthermore, the design and manufacture of the stiffener is embedded within the design variables. At the second level, the actual skin and stiffener lay-ups are obtained using Genetic Algorithms (GAs), accounting for manufacturability and design practices. This two level approach permits the separation of the analysis (strength, buckling, etc), which is performed at the first level, from the laminate stacking sequence combinatorial problem, which is dealt efficiently with GAs at the second level. %B 66th Annual Conference, Madrid, Spain %I Society of Allied Weight Engineers %C Madrid, Spain %P 31 %8 5/28/2007 %G eng %U https://www.sawe.org/papers/3410/buy %9 10. Weight Engineering - Aircraft Design; 23. Weight Engineering - Structural Estimation %M 3410 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE3410 %0 Conference Paper %B 66th Annual Conference, Madrid, Spain %D 2007 %T 3411. Design Optimization in Aircraft Component Pre-Design %A Klemt, Tilo %A Oltmann, Kim %K 10. Weight Engineering - Aircraft Design %X An efficient use of CAE applications in modern aircraft development can lead to shorter development cycles and reduced development costs. This is a sophisticated task for a complex aircraft component with multidisciplinary requirements. In order to get the best possible design, extensive parameter studies are often carried out and the results compared; they may require substantial computations. This situation can often be found in other technical areas and results in the development of a software generation called ?PIDO? (Process Integration and Design Optimization). The traditional CAE development process uses trial and error analysis to find a design that satisfies all of the given requirements. Under normal circumstances, the weight engineer defines the parameters for computing the product attributes. The emerging class of PIDO works, in the opposite direction, by determining the optimal design parameters necessary to meet the target functional performance attributes. This paper is about the primary structure optimization of an aircraft vertical tail. The focus is on the bending-torsion-box variation to find a lightweight solution using a simplified stress model. %B 66th Annual Conference, Madrid, Spain %I Society of Allied Weight Engineers %C Madrid, Spain %P 11 %8 5/28/2007 %G eng %U https://www.sawe.org/papers/3411/buy %9 10. Weight Engineering - Aircraft Design %M 3411 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE3411 %0 Conference Paper %B 66th Annual Conference, Madrid, Spain %D 2007 %T 3412. Influence of Changing Aircraft Masses on Flight and Mission Performance %A Längler, Wolfgang %A Mario Zimmerman %K 10. Weight Engineering - Aircraft Design %K 26. Weight Growth %X The influence of changing aircraft masses on different flight and mission performances is to be demonstrated. In order to make the effects clear, all parameters (engine, fuel quantity, external stores, etc.) but mass are kept unchanged. Some fundamentals of flight mechanics are shown and compared to results of computer simulations of several modern fighters. %B 66th Annual Conference, Madrid, Spain %I Society of Allied Weight Engineers %C Madrid, Spain %P 18 %8 5/28/2007 %G eng %U https://www.sawe.org/papers/3412/buy %9 10. Weight Engineering - Aircraft Design; 26. Weight Growth %M 3412 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE3412 %0 Conference Paper %B 66th Annual Conference, Madrid, Spain %D 2007 %T 3415. Improve Your Sensor Image with Balance %A Mauersberger, Ralf %A Laudan, Timo %A Sellner, Werner %K 10. Weight Engineering - Aircraft Design %K 28. Weight Reduction - Processes %X During the preliminary design process of a new aircraft program, engineers often rely on approximated design parameter estimations based on existing aircraft databases, proprietary, or purchased experts? knowledge, as well as by means of safety factors. Once violations of targeted performance requirements or design constraints are identified too late in the development process, a number of cost and resource intensive iterations on the system design might be induced. The paper discusses a ?recipe? for weight engineers supporting the mass properties life cycle?s front-end by utilizing design freedom in early design phases and reducing changes in later development phases by a well directed approach considering uncertainties in the weight engineering process. Likewise, we address a new (weight) engineered way of thinking and working within the mass properties life cycle process. To substantiate the approach, the paper introduces a case study from the aerospace domain opening new capabilities in the weight engineering process. The authors postulate a higher quality of decisions as well as a negotiation support for weight engineers within the design process. Moreover, the continuous and systematic consideration of uncertainties enables the creation of an improved ?risk picture?, reduces system uncertainties in a target-oriented manner, and enables an optimization of resources with respect to the exchange of information with other disciplines. %B 66th Annual Conference, Madrid, Spain %I Society of Allied Weight Engineers %C Madrid, Spain %P 53 %8 5/28/2007 %G eng %U https://www.sawe.org/papers/3415/buy %9 10. Weight Engineering - Aircraft Design; 28. Weight Reduction - Processes %M 3415 %1 Non-Member Price: $26.50; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 26.5 %4 SAWE3415 %0 Conference Paper %B 66th Annual Conference, Madrid, Spain %D 2007 %T 3418. Virtual Engineering Models for Aircraft Structure Weight Estimation %A Oltmann, Kim %K 10. Weight Engineering - Aircraft Design %X This paper describes an engineering model to enable a multidisciplinary design team to address a wider range of complex design issues much earlier than is common today. The virtual engineering model is dedicated to simulate arbitrary structural layouts that incorporate the finite element method into preliminary aircraft design. Moreover, it provides a more accurate geometrical representation of the entire aircraft, both outer surfaces and structural topology, early in the design process. This aircraft modeling will enable interdisciplinary teams to involve more structural and manufacturing requirements so that their effect on weight and cost is known much earlier, gathering higher design fidelity. The goal has been to develop modeling methods using the parametric-associative approach that will take into account designer inputs throughout agreed parameter interfaces; and it does not require extensive modeling effort several times. To test the herein presented model in an enterprise environment, different use cases on component and assembly level were conducted while satisfying typical aircraft design requirements from a configuration and a structural point of view. The results further indicate that the virtual engineering model could provide decisive advantage in terms of time required to find an appropriate component design, a reliable common data source distributed to all incorporated disciplines, and design fidelity. It also indicates that the much earlier involvement of virtual engineering models in a conceptual design process provides major interdisciplinary interfaces so that all design information are obviously shared by avoiding risk that might appear when several data transformations have to be executed. %B 66th Annual Conference, Madrid, Spain %I Society of Allied Weight Engineers %C Madrid, Spain %P 15 %8 5/28/2007 %G eng %U https://www.sawe.org/papers/3418/buy %9 10. Weight Engineering - Aircraft Design %M 3418 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE3418 %0 Conference Paper %B 66th Annual Conference, Madrid, Spain %D 2007 %T 3421. Structural Sizing or Weight Estimation in Preliminary Aircraft Design %A Wenzel, Joerg %K 10. Weight Engineering - Aircraft Design %X At early stages of aircraft development, accurate weight estimation of primary structure is of great importance. Fast creation of meaningful finite element models is crucial to preliminary design activities in order to assess many configurations and different structural concepts for the aircraft?s airframe. The paper discusses several aspects concerning the development of structural sizing software for this purpose. Legacy software often suffers from being difficult to maintain and extend. The paper presents ideas how to address this problem. The software in development is based on a component-based architecture that strongly reduces unnecessary coupling of independent concepts and makes components reusable in other related software contexts. %B 66th Annual Conference, Madrid, Spain %I Society of Allied Weight Engineers %C Madrid, Spain %P 11 %8 5/28/2007 %G eng %U https://www.sawe.org/papers/3421/buy %9 10. Weight Engineering - Aircraft Design %M 3421 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE3421 %0 Conference Paper %B 64th Annual Conference, Annapolis, Maryland %D 2005 %T 3365. Firefox: Gunship Structural and Material Considerations %A California Polytechnic State University %K 10. Weight Engineering - Aircraft Design %K Student Papers %X

In response to the 2005 American Institute of Aeronautics and Astronautics (AIAA) Team Undergraduate Design Competition, Paladin Aerospace presents Firefox, a new generation gunship to replace the AC-130. Modern demands have outgrown the aging cargo-based airframe of the AC-130H/U Spooky gunship. First introduced during the Vietnam War in 1968, the AC-130 has been modified and improved to meet the continuously evolving demands of modern warfare. In recent years, the proliferation of Anti-Aircraft Artillery (AAA) and low-cost Man Portable Air Defense Systems (MANPADS) has created a gap in defensive technology. Nearly 80% of all fixed-wing aircraft lost during Operation Desert Storm were to MANPAD systems. Spooky, with its low-altitude, predictable, circular attack patterns was particularly vulnerable to these radar and IR seeking devices. The request for proposal (RFP) requires an affordable, highly survivable aircraft to provide lethal firepower during a 4 hour loiter. Firefox moves away from the cargo-based configuration of the AC-130 to a conventional fuselage sized around a single 105mm Rheinmetall tank gun and three 40mm autocannons. This paper focuses on the methods used to reinforce the aircraft for survivability with advanced materials and provide adequate structural support to endure the gun forces. The blast overpressure, recoil force, and heat generated by each of the four guns create material and structural issues unique to a gunship aircraft. Maintaining a low weight is desired to minimize acquisition cost to meet the affordability requirement of the RFP. Only essential areas are reinforced with high strength, resilient, but heavier or more costly materials.

%B 64th Annual Conference, Annapolis, Maryland %I Society of Allied Weight Engineers, Inc. %C Annapolis, Maryland %P 17 %8 5/14/05 %G eng %U https://www.sawe.org/papers/3365/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 3365 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE3365 %0 Conference Paper %B 64th Annual Conference, Annapolis, Maryland %D 2005 %T 3376. Paragon: Structure and Weight Considerations for an Advanced Gunship %A California Polytechnic State University %K 10. Weight Engineering - Aircraft Design %K Student Papers %X

Tip of the Sword Aerospace, of California Polytechnic State University, was presented with the challenge to conceptually design an advanced military gunship. Tip of the Sword Aerospace has responded with Paragon, a highly survivable gunship that has the capability to provide precise and persistent firepower in high threat combat environments. Paragon is in response to the 2004-2005 AIAA Undergraduate Team Design RFP, which calls for an advanced military gunship that can destroy personnel, light armored vehicles, and buildings at low cost. Paragon is an unmanned combat aerial vehicle (UCAV) that employs a conventional configuration with a high wing, H-tail, and tricycle style landing gear. It is equipped with 15,526 pounds of weapons, including two M230 30mm chain guns, 16 HELLFIRE II?s, and 8 GBU-12 Paveway II bombs. Since the Paragon is a UCAV, it can persist in extremely high risk daytime and night-time environments, without risking the lives of a pilot or crew members. This report presents the conceptual approach used to design the Paragon, focusing on the preliminary sizing, weight estimation, and structural layout processes. Initial sizing was primarily driven by the weapons payload requirement of at least 15,000 lbs, a minimum mission radius of 500 n.m., and a four hour time-on-station without refueling. The structural layout was designed to maximize survivability by implementing robust and redundant design features.

%B 64th Annual Conference, Annapolis, Maryland %I Society of Allied Weight Engineers, Inc. %C Annapolis, Maryland %P 31 %8 5/14/05 %G eng %U https://www.sawe.org/papers/3376/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 3376 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE3376 %0 Conference Paper %B 64th Annual Conference, Annapolis, Maryland %D 2005 %T 3377. GRYPHON: Considerations of Weight and Structure in the Design of an Advanced Gunship %A California Polytechnic State University %K 10. Weight Engineering - Aircraft Design %K Student Papers %X

In response to the 2004/2005 AIAA Undergraduate Team Aircraft Design Competition?s request for proposal (RFP) for an Advanced Gunship, Fallen Angel Aerospace is pleased to present Gryphon. Gryphon is both highly survivable against MANPADS and AAA and capable of affordable, precise, and persistent firepower. Dorsal mounted engines shield Gryphon?s exhaust plume effectively reducing IR signature and increasing survivability against MANPAD threats. Gryphon features an H-tail for redundant flight controls as well as redundant systems for increased survivability. The primary weapons featured on Gryphon are the GAU-13 for rapid area suppression and the Bushmaster II for pinpoint attacks. These primary weapons are turret mounted to provide flexible and unpredictable attack patterns. Gryphon?s arsenal includes a side mounted howitzer for persistent and flexible heavy firepower. To provide greater standoff and destructive potentiality, Gryphon also features Hellfire missiles and JDAM bombs. The combat mission profile for Gryphon consists of a 500 n.mi. ingress, followed by a four hour loiter and attack period, and a 500 n.mi. egress. Gryphon is a versatile aircraft that effectively fulfills the close air support, airinterdiction and armed reconnaissance roles. Preliminary capability analyses show that three Gryphon aircraft in the close air support role are capable of responding to a situation anywhere in Iraq within 15 minutes. This same task currently requires approximately eight AC-130?s.

%B 64th Annual Conference, Annapolis, Maryland %I Society of Allied Weight Engineers, Inc. %C Annapolis, Maryland %P 23 %8 5/14/05 %G eng %U https://www.sawe.org/papers/3377/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 3377 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE3377 %0 Conference Paper %B 64th Annual Conference, Annapolis, Maryland %D 2005 %T 3378. LEBOWSKI: Considerations of Weight and Structure in the Design of an Advanced Gunship %A California Polytechnic State University %K 10. Weight Engineering - Aircraft Design %K Student Papers %X

In response to the AIAA Undergraduate Team Aircraft Design Competition?s request for proposal (RFP) for an Advanced Gunship, Mad Hatter Aerospace proudly presents Lebowski. This Unmanned Combat Aerial Vehicle (UCAV) is a remotely?piloted aircraft designed to maximize mission effectiveness while simultaneously minimizing not only mission cost, but also the overall price of the aircraft. It is armed with a complement of guns and droppable ordnance that optimize the precision, persistence, and affordability of the aircraft. The weapons onboard are: two M230 30mm guns, a Bofors L70 40mm Cannon, two GBU-29 Joint Direct Attack Munitions, and four GBU-39 Small Diameter Bombs. Lebowski is equipped with survivability features that have been optimized to meet specific RFP requirements while minimizing weight and maximizing performance. It can cruise at over 400 knots at 30,000 feet and loiter over the target area for four hours at 20,000 feet. The airfoil selection and wing layout are optimized for the RFP mission and feature a modified 6-series airfoil and a slightly blended wing body. Given the RFP requirements for minimum cost and a 400 knot initial cruise at 30,000 feet, a PW 6124 engine is featured on the Lebowski and is sized by taking conservative estimations of future engine technology advances. The structure of the gunship was designed with versatility, survivability, and cost in mind. Lebowski effectively and efficiently fills the niche between the aging AC-130 airframe and the A-10 attack aircraft.

%B 64th Annual Conference, Annapolis, Maryland %I Society of Allied Weight Engineers, Inc. %C Annapolis, Maryland %P 23 %8 5/14/05 %G eng %U https://www.sawe.org/papers/3378/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 3378 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE3378 %0 Conference Paper %B 63rd Annual Conference, Newport, California %D 2004 %T 3322. Weight and Balance Considerations for Flight Test Aircraft On %A McCloud, Darrin %K 10. Weight Engineering - Aircraft Design %X Weight and balance concerns are critically important during the flight testing stage of any aircraft. Many problems encountered during flight testing can be traced back to design requirements concerning aircraft mass properties and weighing. Due to the challenges associated with preliminary aircraft design schedules and practices, many of these requirements are overlooked. There are many unique concerns and requirements that need to be addressed before the test aircraft configuration is finalized. These issues range from weighing difficulties associated with unique test aircraft configurations to the inability to fly required flight profiles. One common mistake involves trying to install too much test equipment on one aircraft, which can result in the previously stated problems. If the test aircraft has sufficiently different mass properties from the production aircraft, it is also possible that the data collected is not truly representative of the production aircraft. Another difficulty concerns inaccurate mass properties, which can lead to issues ranging from invalid data to the possibility of the loss of aircraft and life. Not recognizing these problems and test requirements at an early stage of the program can lead to costly and time consuming fixes at a later date. This paper will concentrate mainly on topics concerning mass properties and aircraft weighing that may be encountered while flight testing small and medium sized 14 CFR (previously FAR) Part 25 aircraft. %B 63rd Annual Conference, Newport, California %I Society of Allied Weight Engineers, Inc. %C Newport, California %P 24 %8 5/15/04 %G eng %U https://www.sawe.org/papers/3322/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 3322 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE3322 %0 Conference Paper %B 62nd Annual Conference, New Haven, Connecticut %D 2003 %T 3310. SumMassProps - An Excel VBA Solution for Summing Mass Properties %A Zimmerman, Robert L. %K 10. Weight Engineering - Aircraft Design %K Mike Hackney Best Paper Award %X

Microsoft Excel is a general-purpose spreadsheet program that lends itself to mass properties calculations. There have been many papers written and presented to the SAWE showing differing techniques to use in determining assembly and vehicle mass properties. The problem with these techniques is that they require a portion of the spreadsheet to be used for storage of intermediate results and the equations used become complex and confusing using Excel?s native symbology. This paper introduces a comprehensive solution set for mass property summation using the built-in Visual Basic for Applications macro language extant in Excel. The solution set, ?SumMassProps.xla,? is embedded in an Excel Add-in. SumMassProps is comprised of three increasingly comprehensive custom functions: CCOG, a function to compute Center of Gravity; CMPROP, a function to compute the complete 10 by X mass property tensor; and CMUP, a function that extends CMPROP by also computing the combined independent uncertainty properties of all ten mass property terms in the mass property tensor. The Add-in also includes facilities to aid in setting up and using the functions in a spreadsheet. By using the Add-in paradigm, the solution set becomes available for use in any spreadsheet that is on the user?s computer. By using SumMassProps, the mass property engineer is freed from spending time debugging spreadsheets and re-inventing the wheel to determine a composite body?s mass properties. This solution set ensures that the proper equations are used and implemented in a consistent manner and speeds up production of reports and ?what-if? scenarios.

%B 62nd Annual Conference, New Haven, Connecticut %I Society of Allied Weight Engineers, Inc. %C New Haven, Connecticut %P 45 %8 5/17/03 %G eng %U https://www.sawe.org/papers/3310/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 3310 %1 Non-Member Price: $22.50; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 22.5 %4 SAWE3310 %0 Conference Paper %B 62nd Annual Conference, New Haven, Connecticut %D 2003 %T 3317. Weights and Materials Considerations in the Design of an Ultra Heavy Lift Aircraft %A California Polytechnic State University %K 10. Weight Engineering - Aircraft Design %K Student Papers %X

Abrams Haulers Incorporated (AHI) presents the AHI-10, an Ultra Heavy Lift Aircraft (UHLA) designed in response to the 2002-2003 AIAA Undergraduate Team Aircraft Design Competition. The AHI-10 fulfills the military?s need to transport massive amounts of equipment in a short period of time, allowing them to deploy entire army battalions within days, satisfying the Rapid Global Mobility Requirements of Joint Vision 2020. The 2002-2003 AIAA request for proposal (RFP) requires designing an aircraft capable of transporting a payload of 1.2 million pounds. Other payload requirements include ten M1A2 Abram tanks, 60 463L pallets, 300 medical litters, as well as 1000 paratroops. The performance requirements include an unrefueled range of 5000 nautical miles at 500 knots at a cruise altitude of 25,000 feet. The aircraft is also required to take off and land in a distance less than 9,000 feet. The vast amount of cargo requirements along with the strict performance requirements set by the RFP requires in-depth analysis of structures and mass properties. The mass properties analysis plays an important role in the aircraft?s design, due to the necessity of reducing aircraft weight in order to achieve the maximum performance necessary to satisfy the RFP requirements. After thorough design analysis, the aircraft has a length of 311 feet and a wingspan of 300 feet, incorporating an all-surface lifting configuration. The AHI-10 uses eight GE 90-115B power plants producing a takeoff thrust of 128,000 pounds force per engine.

%B 62nd Annual Conference, New Haven, Connecticut %I Society of Allied Weight Engineers, Inc. %C New Haven, Connecticut %P 15 %8 5/17/03 %G eng %U https://www.sawe.org/papers/3317/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 3317 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE3317 %0 Conference Paper %B 62nd Annual Conference, New Haven, Connecticut %D 2003 %T 3318. Weight Study of the Gemini : An Ultra-Heavy Lift Aircraft %A California Polytechnic State University %K 10. Weight Engineering - Aircraft Design %K Student Papers %X

Vesper Design Concepts presents Gemini, an Ultra-Heavy Lift Aircraft in response to the 2002-2003 AIAA Team Undergraduate Aircraft Design Competition. This aircraft is required to carry ten M1A2 Abrams tanks over an unrefueled range of 5,000 n. mi. at 500 kts at an altitude of 25,000 ft. or more. As a conventional aircraft would require a wingspan in excess of 400 ft., Gemini utilizes an unconventional c?wing configuration to limit its span to 300 ft. Weight analysis of an aircraft of such unconventional size and configuration has required/resulted in some interesting weight optimization studies. Empirical methods were the main form of analysis used in creating an optimized weight buildup. Analytical methods were only used to contrast with the empirical ones. Initially, very simple methods based on historical trends and basic parameters were used. These led into more complicated empirical relationships focusing on specific aircraft weight groups. Three different methodologies taken from aircraft design texts, were used to define and optimize the Gemini. These methods, along with known aerodynamic quantities, allowed the wing and canard to be optimized for cruise. The placement of different weight groups on the aircraft allowed construction of its pitching moment equation. This in turn allowed the canard to be optimized for trimming the aircraft during takeoff. The landing gear weight was examined in more detail, as it had to be built to take some unusual conditions, like the 15-feet-per-second vertical descent rate. The structural weight was also examined in more detail, as the empirical estimations most likely did not account for a floor loading as high as Gemini?s.

%B 62nd Annual Conference, New Haven, Connecticut %I Society of Allied Weight Engineers, Inc. %C New Haven, Connecticut %P 26 %8 5/17/03 %G eng %U https://www.sawe.org/papers/3318/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 3318 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE3318 %0 Conference Paper %B 62nd Annual Conference, New Haven, Connecticut %D 2003 %T 3319. Hyperion: Considerations in the Design and Weight of an Ultra-Heavy Lift Aircraft %A California Polytechnic State University %K 10. Weight Engineering - Aircraft Design %X DOM Aerospace is proud to present Hyperion, an Ultra-Large Heavy Lift Aircraft (UHLA) designed in response to the 2002-2003 American Institute of Aeronautics and Astronautics (AIAA) Undergraduate Team Aircraft Design Competition. Hyperion incorporates a biplane wing that is optimized to carry a payload of 1.2 million pounds, with provisions to carry ten M1A2 Abrams tanks weighing 1.39 million pounds. Hyperion is designed with weight and cost in mind to operate alongside and replace the C-5 Galaxy in the future. The benefits of a biplane include a decrease in induced drag, reduced fuel burn, and the ability to decrease wingspan, allowing Hyperion to operate from existing airport infrastructure. Hyperion is designed with the goal of minimizing both empty and takeoff gross weight (TOGW). Structural and volume optimizations yielded direct decreases in TOGW, along with aerodynamic and performance optimizations that were incorporated to achieve the lowest fuel burn possible. The most important component of any cargo aircraft is the cargo bay. Hyperion?s cargo bay has the structural capability to carry ten M1A2 Abrams tanks, and the comfort to economically and competitively carry over 1,080 commercial passengers on the cargo deck, with an additional 210 on an upper deck. 1,290 paratroopers can be carried and deployed from both decks of the aircraft. Hyperion is also capable of lifting 72 loaded 463L pallets, 304 Medical Litters with 504 support personnel, 45 HMMWV, six Apache helicopters, and even two inert or one fueled Shuttle Solid Rocket Booster (SRBs). With a design payload range of 5,000 nautical miles and the capability to refuel in flight, Hyperion has the capability to deploy entire battle groups anywhere in the world within a matter of days rather than weeks. The efforts of DOM Aerospace have resulted in an aircraft that has the lowest obtainable empty weight, and the lowest fuel burn for the AIAA RFP?s main mission. Hyperion is designed as a cargo aircraft to carry a 1.2 million pound payload 5,000 nautical miles, with the versatility and provisions to carry a variety of payloads, heavier or lighter, at the sacrifice or addition of fuel and range. Hyperion is DOM Aerospace?s practical and cost effective cargo aircraft that represents the best solution to the RFP. %B 62nd Annual Conference, New Haven, Connecticut %I Society of Allied Weight Engineers, Inc. %C New Haven, Connecticut %P 25 %8 5/17/03 %G eng %U https://www.sawe.org/papers/3319/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 3319 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE3319 %0 Conference Paper %B 61st Annual Conference, Virginia Beach, Virginia, May 18-22 %D 2002 %T 3211. Gulfstream Supersonic Business Jet %A Greiner, Tom %K 10. Weight Engineering - Aircraft Design %X While developing an aircraft for economical supersonic flight is a challenge to itself designing one that can also fly unrestricted supersonically over land is daunting. Gulfstream Aerospace is assessing the feasibility of a Quiet Supersonic Jet (QSJ) enabling worldwide-unrestricted supersonic flight. A QSJ would shrink the world and provide a new tool for international business and government officials. This type of vehicle would create a new aviation market and provide a stepping-stone to larger, more capable high-speed vehicles. The focus of the current study effort is to develop a feasible design that can enter the market in the next ten years using materials and technologies that are currently available or under development. The unique criteria of boom mitigation creates new challenges to the aircraft?s development with weight being a driver for both the aircraft?s performance and sonic boom signature. Gulfstream is evaluating various configurations to meet the sonic boom and other operating requirements. This paper discusses the relationship of the low boom supersonic mission to the weight and balance of the envisioned aircraft configurations. %B 61st Annual Conference, Virginia Beach, Virginia, May 18-22 %I Society of Allied Weight Engineers, Inc. %C Virginia Beach, Virginia %P 19 %8 5/18/02 %G eng %U https://www.sawe.org/papers/3211/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 3211 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE3211 %0 Conference Paper %B 61st Annual Conference, Virginia Beach, Virginia, May 18-22 %D 2002 %T 3231. The Assailant: An Advanced Deep Interdiction Aircraft On CD-R %A California Polytechnic State University %K 10. Weight Engineering - Aircraft Design %K Student Papers %X

Freedom Aerospace, at California Polytechnic State University, San Luis Obispo, is proud to present The Assailant as a contender in the Society of Allied Weight Engineers? 2002 Student Paper Competition. The Assailant is a supersonic, stealth bomber capable of performing, deep interdicting missions of up to a 3,500 nautical mile range at Mach 1.6 supercruise. Using modern statistical weight estimation methods from a variety of reliable sources, aircraft takeoff gross weight is currently estimated 112,500 pounds with a fuel weight fraction of 0.45. Since the aircraft is not expected to enter service for several years from the present, the design benefits from progressive development of new materials and technology to gain positive results in terms of weight control and structural strength. Cost engineering is performed by examining the correlations and carrying out trade studies between the cost of these new advancements and the overall benefits that are gained through their utilization. The Assailant deep interdicting aircraft is designed not only to meet all mission requirements, but also to do so in the most affordable and efficient way possible.

%B 61st Annual Conference, Virginia Beach, Virginia, May 18-22 %I Society of Allied Weight Engineers, Inc. %C Virginia Beach, Virginia %P 84 %8 5/18/02 %G eng %U https://www.sawe.org/papers/3231/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 3231 %1 Non-Member Price: $42.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 42 %4 SAWE3231 %0 Conference Paper %B 61st Annual Conference, Virginia Beach, Virginia, May 18-22 %D 2002 %T 3232. Vendetta: Supercruising Future Strike Aircraft On CD-R %A California Polytechnic State University %K 10. Weight Engineering - Aircraft Design %X Cal Poly proudly presents the Vendetta, a supersonic bomber designed to meet the criterion specified by the AIAA 2001/2002 Undergraduate Team Aircraft Design Request for Proposal. The mission to be flown by the Vendetta consists of a 1,750 nautical mile radius, all of which must be flown at Mach 1.6 at or above 50,000 feet. The aircraft must have low frontal radar cross-section and also be capable of dropping a 9,000-pound weapons payload. The Vendetta is being designed to replace the stealthy F-117 Nighthawk and B-2 Spirit as well as the supersonic F-15 Eagle and B-1 Lancer. The Vendetta?s current takeoff gross weight is 125,000 pounds and its empty weight is 57,000 pounds. Furthermore, an analysis from a low observables standpoint has been made possible by publicly accessible RCS code. The component weight buildup of the Vendetta has been developed using both class I and class II methodologies as well as by assigning mass properties to an actual solid model of the aircraft. Several challenges concerning the balance of the aircraft have been introduced by the immediate and abrupt shift in the aerodynamic center due to the acceleration from subsonic to supersonic Mach numbers. Solutions to this problem have been developed and will be presented in the report. %B 61st Annual Conference, Virginia Beach, Virginia, May 18-22 %I Society of Allied Weight Engineers, Inc. %C Virginia Beach, Virginia %P 117 %8 5/18/02 %G eng %U https://www.sawe.org/papers/3232/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 3232 %1 Non-Member Price: $58.50; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 58.5 %4 SAWE3232 %0 Conference Paper %B 61st Annual Conference, Virginia Beach, Virginia, May 18-22 %D 2002 %T 3258. Boeing Weight and Balance Training %A Moss %A Mitchell %K 10. Weight Engineering - Aircraft Design %X This paper is intended to serve as both a guide and an overview of the development of a Weight and Balance Course. The paper contains four major sections: 1. Reasons for developing a Weight and Balance Course 2. Development of course materials. 3. Presentation to a live audience 4. What the future holds for the course Training and regulatory obligations both drive the content and justification of a Weight and Balance Course. The content suggested by various airlines, combined with various Boeing employee contributions, represented more information than could possibly be covered in a reasonable timetable. Thus in developing the course material a negotiated ?middle ground? was necessary. This paper describes the decision drivers and the result of those decisions. In addition, some time is dedicated to potential future additions and enhancement for the existing course. Upon completion of this paper the reader should have a good understanding of what is involved in developing a Weight and Balance Course. The reader should also understand why the materials that are included in the Boeing offered course are there, as well as why some topics are not. %B 61st Annual Conference, Virginia Beach, Virginia, May 18-22 %I Society of Allied Weight Engineers, Inc. %C Virginia Beach, Virginia %P 13 %8 5/18/02 %G eng %U https://www.sawe.org/papers/3258/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 3258 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE3258 %0 Conference Paper %B 61st Annual Conference, Virginia Beach, Virginia, May 18-22 %D 2002 %T 3272. AIAA Paper 2002-3426 The X-47A Pegasus, From Design To Flight %A Mazur, David %K 10. Weight Engineering - Aircraft Design %X This paper covers the evolution of the X-47A Pegasus. It addresses the objectives envisioned in developing the concept, the design and construction methods used in building the prototype, elements of the subsystems included in the air vehicle and the integration procedures used to complete the vehicle. The presentation summarizes the results of initial testing of the air vehicle and the planned flights scheduled to be conducted at Naval Air Warfare Center (NAWC) China Lake, CA in 2002. %B 61st Annual Conference, Virginia Beach, Virginia, May 18-22 %I Society of Allied Weight Engineers, Inc. %C Virginia Beach, Virginia %P 8 %8 5/18/02 %G eng %U https://www.sawe.org/papers/3272/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 3272 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE3272 %0 Conference Paper %B 60th Annual Conference, Arlington, Texas, May 19-23 %D 2001 %T 3144. The Crossbow - Blended Wing Body Common Support Aircraft Design for the US Navy (Student paper Cal Poly,SLO) %A Akers %A Patangui %A Guzman %A Gardenhire %A Atwood %A Barthel %A Ward %K 10. Weight Engineering - Aircraft Design %X Archer Aero is proud to present Crossbow, a Common Support Aircraft designed in response to the 2000-2001 AIAA Undergraduate Team Aircraft Design Request for Proposal. The Crossbow incorporates a lightweight design into a unique aircraft that is optimized to perform several missions. Although a blended wing configuration has not been used on carrier suitable aircraft, every aspect of the Crossbow proves that it is capable in meeting every requirement of a highly functional Naval aircraft. One of the most important aspects of the Navy Common Support Aircraft is its degree of commonality and ability to affordably replace its highly successful predecessors. This is apparent in the design of the Crossbow, particularly, with regard to the manufacturing of this aircraft. The Crossbow utilizes two airframes for the four mission variants; the only difference among them is the aft center body section, which is a convenient manufacturing break point. During the manufacturing stages, mission specific equipment is added to distinguish each variant. The efforts of Archer Aero have resulted in an innovative but practical solution to the RFP requirements and will prove to be a cost effective replacement for the several aging aircraft in the Navy fleet. The Crossbow not only represents a viable solution to the AIAA design competition, but for the entire CSA program. %B 60th Annual Conference, Arlington, Texas, May 19-23 %I Society of Allied Weight Engineers, Inc. %C Arlington, Texas %P 90 %8 5/19/01 %G eng %U https://www.sawe.org/papers/3144/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 3144 %1 Non-Member Price: $45.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 45 %4 SAWE3144 %0 Conference Paper %B 60th Annual Conference, Arlington, Texas, May 19-23 %D 2001 %T 3145. The Penguin - Common Support Aircraft Design for the US Navy (Student Paper Cal Poly SLO) %A Mayer %A Birtalan %A Okada %A Sabino %A Gerber %A Pelascini %A Tucay %K 10. Weight Engineering - Aircraft Design %X Transcendental Engineering Design is proud to present the Penguin as a contender to the Common Support Aircraft RFP. A single airframe is the basis for all mission variants. The modifications needed to convert the aircraft between its Airborne Early Warning, Carrier Onboard Delivery, Electronic Surveillance, and Anti-Submarine Warfare/Anti-Surface Warfare are relatively small and can be accomplished at a land base. By maximizing commonality between the four mission variants, development and operational costs are minimized. The Penguin uses existing propulsion, materials, and avionics technology to accelerate the development required. All variants have takeoff weights ranging from 56,000 pounds to 64,000 pounds. The AEW aircraft utilizes an electronically steered array radar, reducing drag and fuel consumption to a point comparable to the other missions. This radar is similar to the Ericsson ERIEYE utilized by the Swedish Air Force. Pallet mounted avionics and systems ensure that the Penguin can be reconfigured readily at a land base if Navy mission requirements vary. The Penguin is powered by two Pratt & Whitney PW800 turbofans. These engines are currently in development and represent the next generation of high-bypass ratio turbofans. Due to the low fuel burn of these engine, all fuel can be carried in the wings or on pylons. The Penguin is capable of serving as a tanker, carrying a total of 30,000 pounds of fuel that may be transferred with the use of standard buddy packs. This paper details the work done by Transcendental Engineering Design to ensure that the Penguin is the most practical solution to the AIAA RFP. %B 60th Annual Conference, Arlington, Texas, May 19-23 %I Society of Allied Weight Engineers, Inc. %C Arlington, Texas %P 130 %8 5/19/01 %G eng %U https://www.sawe.org/papers/3145/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 3145 %1 Non-Member Price: $65.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 65 %4 SAWE3145 %0 Conference Paper %B 60th Annual Conference, Arlington, Texas, May 19-23 %D 2001 %T 3165. Helicopter Preliminary Design %A Lucero %A Landers %A Henthorn %K 10. Weight Engineering - Aircraft Design %K 11. Weight Engineering - Aircraft Estimation %X The scope of this paper will be limited to design of helicopters in the conceptual phase of preliminary design. That is, sufficient activities to result in a general arrangement with appropriate levels of detail regarding inboard profile drawings, performance estimates, etc. Key Topics: Discussion of the steps necessary to arrive at a mission definition. Development of top level requirements to achieve the stated mission. Creation of an initial weight estimate. Discussion of an approach to conceptual configuration development. Discussion of basics for determining power required and how to estimate fuel requirements. %B 60th Annual Conference, Arlington, Texas, May 19-23 %I Society of Allied Weight Engineers, Inc. %C Arlington, Texas %P 109 %8 5/19/01 %G eng %U https://www.sawe.org/papers/3165/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN; 11. WEIGHT ENGINEERING - AIRCRAFT ESTIMATION %M 3165 %1 Non-Member Price: $54.50; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 54.5 %4 SAWE3165 %0 Conference Paper %B 60th Annual Conference, Arlington, Texas, May 19-23 %D 2001 %T 3167. The CarterCopter Heliplane Transport (CCH-T) %A Carter, Jay, Jr. %K 10. Weight Engineering - Aircraft Design %X The technology being flown on the CarterCopter (CC) Technology Demonstrator (CCTD) since September 1998 shows great promise for the design of V/STOL, high-speed, and long-range aircraft of all sizes. A new design concept called the CC Heliplane emerged in early 2000 from the CCTD R&D program. This revolutionary V/STOL aircraft will take off, hover and land like a helicopter. At speeds above 100 MPH, it will convert to a CC high-technology gyroplane by unloading its rotor onto very efficient high-aspect ratio wings and, in the process, slowing its rotor to minimize profile drag and provide flight efficiency comparable to a fixed-wing aircraft of the same gross weight (GW) The CC Heliplane concept was used to design the CC Heliplane-Transport (CCH-T). The CCH-T is especially impressive for being huge. The 150,000 lb. max GW VTOL aircraft (200,000 lb. max GW in STOL mode) will have a larger cargo compartment and carry a heavier payload than the current C-130J-30 Hercules. The CCH-T is designed to cruise at 450 MPH at 32,500 ft altitude and carry a 45,000 lb. payload for 1,500 miles with a 45-minute fuel reserve. When operating as a STOL aircraft, its range almost triples. There is no new technology involved in the design of the CCH-T except what is currently flying on the CCTD. %B 60th Annual Conference, Arlington, Texas, May 19-23 %I Society of Allied Weight Engineers, Inc. %C Arlington, Texas %P 16 %8 5/19/01 %G eng %U https://www.sawe.org/papers/3167/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 3167 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE3167 %0 Conference Paper %B 60th Annual Conference, Arlington, Texas, May 19-23 %D 2001 %T 3172. Advanced Tiltrotor Design %A Lloyd, John %K 10. Weight Engineering - Aircraft Design %X Development of any new aircraft from preliminary design through first flight involves interesting design challenges and solutions. This is especially true if the aircraft represents a new niche or technology relative to government and industry requirements and experience base. The Bell-Agusta BA609 will be the world's first production civil tilt-rotor. First flight is scheduled for later this year. This paper will address two specific configuration design issues unique to tilt-rotors faced during development and delve into the importance of weight reduction very early on the 609 program. Determining the proper wing and pylon location, with respect to the fuselage, to achieve the maximum aircraft longitudinal operating envelope involved consideration of both fixed and rotary wing conditions. Ideally, the wing and pylon should be located such that the aircraft c.g. is well within the desired wing % M.A.C. in airplane mode, and nearly centered on the rotor in helicopter mode. The approach taken to achieve optimum location, methods of conducting the early balance estimates, and results are all addressed. Another configuration design challenge arose from well-publicized turbine burst incidents on airliners during the 1990's. FAA concerns on this subject required the 609 design comply with turbine burst survivability. The selection of a highly reliable PT6 engine with no recorded turbine bursts in service would not be enough to satisfy the FAA or us regarding aircraft safety. The engine and drive systems were rearranged within the nacelles to reduce the risk of aircraft loss. The cost, weight, and schedule impacts of rearranging the nacelles were weighed against the weight and physical limitations of shielding the engines. Shot-line analysis, system failure analysis, and nacelle to ground clearance were all critical drivers in the final design. The importance of aggressive weight reduction very early in the 609 program was critical in bringing the product through development. Without many of the criteria reductions and management weight reviews, the aircraft would be too heavy to perform its missions effectively, and would likely have been cancelled before more capital was invested. Weight growth is an inherent part of a development program, and should be planned for and resisted all through the design phase. The emphasis on early weight reduction as on the 609, followed by a weight control program that is integral with design as on the V-22, reflects the best approach for the next new development aircraft. %B 60th Annual Conference, Arlington, Texas, May 19-23 %I Society of Allied Weight Engineers, Inc. %C Arlington, Texas %P 32 %8 5/19/01 %G eng %U https://www.sawe.org/papers/3172/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 3172 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE3172 %0 Conference Paper %B 59th Annual Conference, St. Louis, Missouri, June 5-7 %D 2000 %T 3001. Technology Evaluation Via Loss Managment Models Formulated in Terms of Vehicle Weight or Wither a Scheme for Vehicle Fuel %A Roth, B %A Mavris, Dr. , D %K 10. Weight Engineering - Aircraft Design %K Mike Hackney Best Paper Award %X

Mass properties engineering is today an established field and an indispensable part of the aerospace vehicle design process. Detailed bookkeeping schemes have been developed to track constituent component weights in extreme detail, down to the last rib and rivet. Given this situation, i t may be more accurate to refer to this field as "empty weights engineering "because the focus has always been primarily on management and tracking of vehicle empty weight. Meanwhile, one of the largest weight fractions, fuel weight, is bookkept in a single lump and largely ignored (except inasmuch as it impacts vehicle size and growrh factor). Itis intuitively obvious that the aerothermodynamic losses due to the engine, airframe systems, and aerodynamic drag of the vehicle are the fundamental drivers on fuel weight and should therefore be expressible as increments in fuel weight chargeable to each loss mechanism. The sum of all chargeable fuel weights is equal to the total fuel weight required to complete a prescribed mission. The intent of this paper is to formulate a method for quantifying thermodynamic performance in terms of mission fuel chargeable to each thermodynamic loss mechanism. This is then used in conjunction with known vehicle zero fuel weight groups to estimate the gross weight chargeable to each functional component of the vehicle. The results show that chargeable vehicle gross weight canbe used as a common figure of merit linking mass properties and performance aspectsof vehicle design. This method is then demonstrated for a Northrop F-5E aircraft, and the fuel weight breakdown is analytically calculated for the design mission. The results of this analysis show that 37.3% of the F-5E subsonic mission fuel requirement is due to propulsion system losses, 36.8% is chargeable to aerodynamicdrag,and 24.3% is chargeable to vehicle empty weight.This translates into a chargeable fuel cost of roughly $173.90, $171.76, and $113.53 for each of these three loss mechanisms, respectively. Finally, the usefulness of this technique as a means of technology evaluation is considered. The strengths of this method are that it allows quantification of both weight and performance aspects of technology benefits in a single figure of merit. and also enables one to ascertain the benefits of individual technologies even when applied as part of a suite of technologies.

%B 59th Annual Conference, St. Louis, Missouri, June 5-7 %I Society of Allied Weight Engineers, Inc. %C St. Louis, Missouri %P 25 %8 6/5/00 %G eng %U https://www.sawe.org/papers/3001/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 3001 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE3001 %0 Conference Paper %B 59th Annual Conference, St. Louis, Missouri, June 5-7 %D 2000 %T 3003. Evaluation of Equivalent Laminated Plate Solution (ELAPS) in HSCT Sizing %A Stone, Steven %A Henderson, Joseph %A Nazari, Mark %A Boyd, William %A Becker,Bradley %A Bhatia, Kumar %A Giles, Gary %A Wrenn, Gregory %K 10. Weight Engineering - Aircraft Design %X The motivation for evaluating ELAPS was to determine its suitability as a quick and reliable tool for conceptual and early preliminary design. The expectation was that ELAPS would predict a better structural weight than parametric weight equations since its weight is determined from structural optimization with both strength and flutter constraints. An additional motivation was to eventually utilize the functional representation of ELAPS in shape optimization. Results from the current version of ELAPS were compared against Elfini. The comparisons included static displacements and stresses, natural vibration frequencies and mode shapes, strength optimization, flutter optimization, and simultaneous strength and flutter optimization. Elfini is a mature, well-understood, FEM tool with many years of development effort behind it. Although previous studies have proven the merits of ELAPS for preliminary structural analysis, little research has been accomplished to formally test an ELAPS based flutter optimization. Optimization with strength constraints worked well and provided final weights comparable to Elfini. But the flutter optimization, and simultaneous strength and flutter optimizations converged to significantly different weights. This could partly be attributable to analytical and model differences. There were differences of up to 10% in a few of the first 10 modal frequencies, primarily due to disagreement in stiffness for the HSCT uniform gauge wing. Thus, for ELAPS to provide an attractive option for structural sizing and shape optimization, there needs to be further investments in (1) improving ELAPS? static stiffness correlation with FEM?s, (2) developing an automated parametric input/output graphical interface for ELAPS, (3) improving the robustness of the ELAPS structural representation, (4) improving the computational efficiency of ELAPS and its associated optimization system, and (5) developing ELAPS flutter and shape optimization capabilities In some sense, it is unfair to compare ELAPS with mature FEM codes with years of development effort. However, unless significant improvement to ELAPS is made soon, it will be difficult for ELAPS to compete with the rapid automation of FEM codes for simplified analysis and design. %B 59th Annual Conference, St. Louis, Missouri, June 5-7 %I Society of Allied Weight Engineers, Inc. %C St. Louis, Missouri %P 12 %8 6/5/00 %G eng %U https://www.sawe.org/papers/3003/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 3003 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE3003 %0 Conference Paper %B 59th Annual Conference, St. Louis, Missouri, June 5-7 %D 2000 %T 3012. ""CYCLOPS"" - An Uninhabited Cruise Missile Launcher %A Bach, J B %A Kutzmann, A J %A Deedon, R P %A Stewart III, D B %A McDonald, M C %A Valenzuela, L J %A Lawson, J C %A Barneby, L M %K 10. Weight Engineering - Aircraft Design %X The Poseidon Design Group is proud to present Cyclops, an uninhabited cruise missile carrier designed in response to the 1999-2000 AIAA Undergraduate Team Aircraft Design Competition. Cyclops incorporates low cost, low risk technology into an aircraft optimized to carry and deploy Air Launched Cruise Missiles. Its simple configuration, high airframe life, and low operating cost will allow Cyclops to operate far into the future much like the B-52. The most important component to any bomber is its bomb bay, and this is reflected in Cyclops' design. The aircraft has one bomb bay fore and one aft of the wing carry through box. Each bay houses five cruise missiles in a rotary door configuration, however, the structure for the weapons doubles as a load-bearing member for both the payload and the flight loads. In so doing, Cyclops maintains the minimum total fuselage volume and weight needed to carry the payload. With a cruise missile range of over 700 nautical miles, Cyclops will remain out of the combat theater for the duration of the mission. A benign mission profile drives a small maneuvering envelope, providing an excellent oppertunity for an uninhabited aircraft. The benefits of an uninhabited weapons platform include: reduced parasite drag, reduced empty weight, improved station keeping capability, and reduced training and operations costs. The culmination of the Poseidon Design Group's efforts resulted in a cost effective, lethal aircraft, able to accomplish the AIAA's RFP. Cyclops was designed as a standoff delivery platform whose only purpose was to carry ten AGM-86C cruise missiles four thousand nautical miles. Innovation was only allowed when improving Cyclops ability to complete its mission, or reducing the life cycle cost of the aircraft. Cyclops is a result of the Poseidon Design Group's philosophy, to develop a practical and cost effective bomber that represents the ideal solution to the RFP. %B 59th Annual Conference, St. Louis, Missouri, June 5-7 %I Society of Allied Weight Engineers, Inc. %C St. Louis, Missouri %P 90 %8 6/5/00 %G eng %U https://www.sawe.org/papers/3012/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 3012 %1 Non-Member Price: $45.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 45 %4 SAWE3012 %0 Conference Paper %B 59th Annual Conference, St. Louis, Missouri, June 5-7 %D 2000 %T 3027. Progress Report on IHPTET Technology Implementations %A Reed, Jim %K 10. Weight Engineering - Aircraft Design %X Presentation %B 59th Annual Conference, St. Louis, Missouri, June 5-7 %I Society of Allied Weight Engineers, Inc. %C St. Louis, Missouri %P 23 %8 6/5/00 %G eng %U https://www.sawe.org/papers/3027/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 3027 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE3027 %0 Conference Paper %B 59th Annual Conference, St. Louis, Missouri, June 5-7 %D 2000 %T 3030. Guide to Differences Between MIL-STD-1374A and SAWE Recommended Practice 8A %A Dudley M Cate %K 10. Weight Engineering - Aircraft Design %X On 30 September 1977, the U.S. Department of Defense issued MIL-STD-1374A, ?Weight and Balance Data Reporting Forms for Aircraft (including Rotorcraft).? It thereby became the latest in a series of U. S. Military Standards that provided specific formats and accompanying instructions for reporting the weights of heavier-than-air flight vehicles and their constituent elements. In 1995, the Society of Allied Weight Engineers (SAWE) adopted MIL-STD-1374A as a Society Recommended Practice, SAWE RP-8. In 1997, the SAWE approved a revision to RP-8, identified as Revision A to RP-8 or RP-8A. It is dated June 1, 1997. The purpose of this paper is to identify the substantive differences between MIL-STD-1374A (RP-8) and RP-8A. The paper may be of particular value to persons undertaking to convert the reporting for a particular aircraft model from the MIL-STD-1374A format to the RP-8A format, or undertaking to convert a general weight records system (database program) from one standard to the other. The paper identifies the changes by use of generic descriptions; it does not call out each and every specific difference between the two documents. A conscientious attempt has been made to identify all substantive differences between the two standards. However the author and the SAWE do not certify that all such changes have been included herein, nor do they accept responsibility for any omissions or errors herein. Also, it should be recognized that differences that might be of relatively minor impact with respect to one aircraft design or weight record system might have major impact with respect to another aircraft or system. %B 59th Annual Conference, St. Louis, Missouri, June 5-7 %I Society of Allied Weight Engineers, Inc. %C St. Louis, Missouri %P 22 %8 6/5/00 %G eng %U https://www.sawe.org/papers/3030/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 3030 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE3030 %0 Conference Paper %B 59th Annual Conference, St. Louis, Missouri, June 5-7 %D 2000 %T 3035. Boeing Type III Automatic Overwing Exit %A Brown, Stephen %K 10. Weight Engineering - Aircraft Design %X Automatic Overwing Exit (AOE) Presentation AOE Overview Safety Improvement Initiative AOE Design and Weight Flight Crew Training Safety Improvement features %B 59th Annual Conference, St. Louis, Missouri, June 5-7 %I Society of Allied Weight Engineers, Inc. %C St. Louis, Missouri %P 26 %8 6/5/00 %G eng %U https://www.sawe.org/papers/3035/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 3035 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE3035 %0 Conference Paper %B 58th Annual Conference, San Jose, California, May 24-26 %D 1999 %T 2462. Effect of Control Surface Balance on Flutter %A Scheulen, M %K 10. Weight Engineering - Aircraft Design %X Mass properties' engineers often are concentrating on creating and maintaining the most accurate and current weight database possible on our aircraft or system. They tend to lose sight of why accurate weight data is important. While having accurate weight data is intrinsically valuable, it can have a major impact on design decisions and even on the viability of a design. Some systems are more sensitive to changes in weight and center of gravity than others. One of the critical elements in the design of aircraft is "flutter modes". Every moving body has vibration frequencies. It is important to avoid coupling frequency modes in the airplane components. This can have catastrophic results, including loss of property and lives. Excessive vibration can result in metal fatigue, even without catastrophic failure. It is important that accurate weight and balance data be available to design engineers early in a program. Many problems can be avoided if a potential flutter situation is identified early in a program. An important way the mass properties' engineer can assist in preventing flutter is by working closely with loads and flutter engineers to optimize the control surface balance. Parametric studies are run by loads and flutter engineers to determine the optimal balance weight and location to achieve no coupling of vibration modes. The mass properties' engineer needs to assure that the mass properties' data provided for future analyses reflects this optimal value and the system balance about its hinge line is within the limits established. %B 58th Annual Conference, San Jose, California, May 24-26 %I Society of Allied Weight Engineers, Inc. %C San Jose, California %P 16 %8 5/24/99 %G eng %U https://www.sawe.org/papers/2462/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 2462 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE2462 %0 Conference Paper %B 58th Annual Conference, San Jose, California, May 24-26 %D 1999 %T 2468. The UK MoD COEIA Process - Implications for Preliminary Design %A Priest, A J %K 10. Weight Engineering - Aircraft Design %X This paper describes the Combined Operational Effectiveness and Investment Appraisal (COEIA) process used by the UK Ministry of Defence (MoD). This is a mandatory procedure at a number of points in any major UK defence equipment procurement programme. It provides the basis for the authorization of each of the key phases of the programme. The COEIA process combines assessment of both the costs of defence equipment options (on a total-life basis) and the military effectiveness of those options. The COEIA has proved an efficient means of identifying the defence equipment options that provide best value for money and the most robust solutions to UK military requirements. US defence contractors are increasingly encountering the complex UK MoD COEIA process in competing in the UK defence market. This paper outlines the UK MoD implementation of the COEIA process, and its important role in MoD decision making. It stresses the genuine MoD need for the comprehensive engineering data typically sought from US companies, via appropriate US DoD channels, for UK COEIA purposes. It emphasizes that MoD strictly enforces both company proprietary rights and US DoD release conditions on such data. The paper describes the COEIA process as applied in the UK MoD Air Systems area with which the Miter is most familiar. The theory and practice of the basic operational analysis element of the COEIA process are as well understood in the US defence community as they are in the UK. This paper therefore focuses on the context in which the UK MoD COEIA process works, in particular on the stringent independent COEIA audit required, and on the UK-particular objectives the COEIA seeks to meet. The paper also gives some tentative views on how the MoD's ongoing Smart Procurement Initiative might affect the COEIA process. The paper reflects the author's personal experience and view of the complex and dynamic COEIA process in the UK, with the final impact of the UK Strategic Defence Review and the UK MoD Smart Procurement Initiative on COEIAs still uncertain. The paper does not necessarily reflect the official views of the UK MoD. %B 58th Annual Conference, San Jose, California, May 24-26 %I Society of Allied Weight Engineers, Inc. %C San Jose, California %P 13 %8 5/24/99 %G eng %U https://www.sawe.org/papers/2468/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 2468 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE2468 %0 Conference Paper %B 58th Annual Conference, San Jose, California, May 24-26 %D 1999 %T 2483. H-1 Upgrade: AH-1Z and UH-1Y Weight Control Process Update %A Kaiser, S %A Evans, A %K 10. Weight Engineering - Aircraft Design %X (None - PRESENTATION) %B 58th Annual Conference, San Jose, California, May 24-26 %I Society of Allied Weight Engineers, Inc. %C San Jose, California %P 36 %8 5/24/99 %G eng %U https://www.sawe.org/papers/2483/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 2483 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE2483 %0 Conference Paper %B 57th Annual Conference, Wichita, Kansas, May 18-20 %D 1998 %T 2435. Weight History of the U.S. Army CH-47 Helicopter %A Donaldson, N J %K 10. Weight Engineering - Aircraft Design %X This paper provides a brief review of the weight history of the U.S. Army CH-47 Series Helicopter. The CH-47 Series is a twin engine, tandem rotor helicopter filling the U.S. Army's medium lift cargo mission. The aircraft can carry a variety of internal and external cargo. The design is essentially unchanged from the 30,000 pound A model of the early 60's to the current 50,000 pound CH-47D. A proposed Improved Cargo Helicopter will provide continued medium lift capability at reduced operating and support costs. Data is provided from a number of informal sources. This paper is not intended as a formal technical or specification description by either the U.S. Army Aviation and Missile Command or by Boeing Helicopters. %B 57th Annual Conference, Wichita, Kansas, May 18-20 %I Society of Allied Weight Engineers, Inc. %C Wichita, Kansas %P 16 %8 5/18/98 %G eng %U https://www.sawe.org/papers/2435/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 2435 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE2435 %0 Conference Paper %B 57th Annual Conference, Wichita, Kansas, May 18-20 %D 1998 %T 2439. H-1 Upgrade: AH-1Z and UH-1Y Weight Control Process %A Kaiser, S %A Evans, A %K 10. Weight Engineering - Aircraft Design %X (None - PRESENTATION) %B 57th Annual Conference, Wichita, Kansas, May 18-20 %I Society of Allied Weight Engineers, Inc. %C Wichita, Kansas %P 50 %8 5/18/98 %G eng %U https://www.sawe.org/papers/2439/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 2439 %1 Non-Member Price: $25.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 25 %4 SAWE2439 %0 Conference Paper %B 56th Annual Conference, Bellevue, Washington, May 19-21 %D 1997 %T 2373. The K-Max Helicopter a Unique Lifting Efficiency %A Haliscak, G W %K 10. Weight Engineering - Aircraft Design %X The Kaman K-l200 ""K-MAX"" Helicopter (Figure 1) was certified in August of 1994. It is the only FAA certified aircraft designed, built, tested, and operated for the continuous repetitive external load mission. It is a single-seat, single engine and transmission, composite dual-rotor aircraft. The aircraft design is optimized around the pilot and the external load attaching point (the hook). The cockpit and airframe are configured for maximum use of vertical reference flying (directly viewing the load from the cockpit) and minimizing pilot workload. The hook"" supporting structure"" and dynamic components have been tested to withstand daily"" continuous"" repetitive maximum load lifting throughout the life of the airframe. Operations performed to date include: logging, firefighting, seismic exploration, construction, agricultural, re-supply via external load, and emergency rescue. The heaviest usage is logging followed by construction and firefighting. Aircraft have been operating in the U.S., Canada, Japan, Switzerland, Germany, Liechtenstein, and Bolivia in commercial applications, and at sea for the U.S. Navy. The K-MAX Helicopter is demonstrating a unique lifting efficiency in the commercial and military utility helicopter markets. %B 56th Annual Conference, Bellevue, Washington, May 19-21 %I Society of Allied Weight Engineers, Inc. %C Bellevue, Washington %P 10 %8 5/19/97 %G eng %U https://www.sawe.org/papers/2373/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 2373 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE2373 %0 Conference Paper %B 56th Annual Conference, Bellevue, Washington, May 19-21 %D 1997 %T 2375. Weight Control Overview S-92 Medium Lift Helicopter Program %A Sostilio, N %K 10. Weight Engineering - Aircraft Design %X The S-92 is a medium lift helicopter developed to meet the latest commercial safety standards (FAR/JAR 29). The development of an aircraft always comes with new challenges and the S-92 is no exception. Some of these challenges always seem to remain the same from program to program such as solving difficult technical issues and finding ways to meet schedule and budget commitments. The S-92 development program came with these challenges along with some unique ones, many brought on by the environment which is different from Sikorsky Aircraft Corporation's historical business experience including: 1. The S-92 is a commercial program rather than a government/military program. 2. Suppliers have participated in the program as partners with Sikorsky Aircraft Corporation(SAC) rather than in a more traditional supplier relationship. 3. Partnership has involved foreign firms with significantly different cultures, value systems and motivators. Each of the above factors has brought new and unique challenges to the entire S-92 team. Being a commercial program brought new competitive pressures and cost constraints particularly in light of the fact that the program is being funded entirely by SAC, partner and supplier funds with no specific or guaranteed customers. New FAR/JAR 29 design requirements such as flaw tolerance, high intensity radiated fields (HIRF), bird strike, competitive issues including crashworthiness, cost (acquisition and maintenance) and cabin size, and new approaches to building the aircraft including build to order all brought on unique challenges faced by the team. While it was the original intention of this paper to provide a complete overview of the S-92 weight control efforts and the unique challenges faced by S-92 Mass Properties personnel which included in-house as well as partner issues, a decision was made to focus on the weight control techniques and challenges involved in having international partners. Unique challenges faced by the weight control team include: Partners - five international Transfer of weight control techniques and methodology Development of Weight Allocations Partner Interface Issues The new and unique challenges of the in-house design can be the subject of a future SAWE paper. %B 56th Annual Conference, Bellevue, Washington, May 19-21 %I Society of Allied Weight Engineers, Inc. %C Bellevue, Washington %P 31 %8 5/19/97 %G eng %U https://www.sawe.org/papers/2375/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 2375 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE2375 %0 Conference Paper %B 56th Annual Conference, Bellevue, Washington, May 19-21 %D 1997 %T 2382. The Impact of Weight Analysis and Control on Joint Strike Fighter Development %A Jackson, S K, Jr. %K 10. Weight Engineering - Aircraft Design %X The Joint Strike Fighter (JSF) program as currently planned will be the dominant new fighter program for the next two decades. Several features of the program make weight predictions and weight control particularly vital to program success. These factors include the fact that the aircraft must meet differing requirements of at least four different services, must adhere to strict cost/affordability constraints, and in one version must meet demanding Short Takeoff/Vertical Landing (STOVL) requirements. The impact of these factors on weight analysis and control methods will be described from a Chief Engineer' s perspective, beginning with a few historical observations and ending with recommendations and challenges to the weight engineering community. %B 56th Annual Conference, Bellevue, Washington, May 19-21 %I Society of Allied Weight Engineers, Inc. %C Bellevue, Washington %P 22 %8 5/19/97 %G eng %U https://www.sawe.org/papers/2382/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 2382 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE2382 %0 Conference Paper %B 56th Annual Conference, Bellevue, Washington, May 19-21 %D 1997 %T 2383. The V/STOL Propulsion Weight Fraction Revisited %A Sanders, K %K 10. Weight Engineering - Aircraft Design %X In light of the current JSF prototype program, the causes for the 40 year long cyclical and stymied efforts to develop the fixed-wing high-speed powered-lift V/STOL aircraft are briefly reviewed. Four imperative design objectives are suggested and defined. Two of these are: 1) a benign exhaust footprint, and 2) a low propulsion weight fraction of take-off weight. The propulsion group weight fractions of 45 designs, encompassing ten powered-lift concepts, are plotted Vs conception year, It is shown that airframe weight savings have the potential to offset propulsion weight increments. Cruise engine weight is the largest part of total propulsion weight, and bypass ratio one of the most important cycle variables. Therefore, a correlation of engine thrust/weight ratio with bypass ratio for 17 engines was made to trend the upper and lower bounds of the scatter band. %B 56th Annual Conference, Bellevue, Washington, May 19-21 %I Society of Allied Weight Engineers, Inc. %C Bellevue, Washington %P 13 %8 5/19/97 %G eng %U https://www.sawe.org/papers/2383/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 2383 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE2383 %0 Conference Paper %B 56th Annual Conference, Bellevue, Washington, May 19-21 %D 1997 %T 2385. An Approach to Weight Strategy in Conceptual and Preliminary Design Phases %A Liu, J C H %K 10. Weight Engineering - Aircraft Design %X This paper gives a general overview of the inter-relations between the weights predicted by the weight engineers and the strategic parameters considered by the management in the conceptual and preliminary design phases. Due to the fact that towards the end of the preliminary design phase, at the latest when the contracts with the launching customers are to be signed, the strategic parameters must have been fixed and the final policy decisions should have been made. So, these weights and parameters discussed in this paper are only for phases up to go-ahead. Also, a general guideline of the process of the weight strategy decisions is described. Although it varies with different companies and for different projects, there are certain commonalities. this paper is based on the strategy discussions of some Airbus Industrie new projects. %B 56th Annual Conference, Bellevue, Washington, May 19-21 %I Society of Allied Weight Engineers, Inc. %C Bellevue, Washington %P 18 %8 5/19/97 %G eng %U https://www.sawe.org/papers/2385/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 2385 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE2385 %0 Conference Paper %B 56th Annual Conference, Bellevue, Washington, May 19-21 %D 1997 %T 2391. Evaluation of Weight During Aircraft Design: An Integrated Approach %A Frank, M D %K 10. Weight Engineering - Aircraft Design %X For an aircraft to be successful in the marketplace, design decisions must consider all impacts on the customer. Of particular importance is the decision with regard to potential weight increases. Since weight affects performance, and thus the customer's ""bottom line"", weight changes should be evaluated with a ""dollar based"" metric. This paper outline a framework for evaluating weight during detail design using a hypothetical study aircraft. The approach explicitly links the decisions of customers and original equipment manufacturers so the effects of a weight change can be better understood. Airline operations are emphasized, but the approach can be extended to other uses. Both aircraft performance and data provided are hypothetical and do not reflect current or future aircraft. %B 56th Annual Conference, Bellevue, Washington, May 19-21 %I Society of Allied Weight Engineers, Inc. %C Bellevue, Washington %P 13 %8 5/19/97 %G eng %U https://www.sawe.org/papers/2391/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 2391 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE2391 %0 Conference Paper %B 56th Annual Conference, Bellevue, Washington, May 19-21 %D 1997 %T 2399. The Case for Transport Sail Craft %A Roeseler, B %A Schmidt, T %A Beattie, A %A Roeseler, C %K 10. Weight Engineering - Aircraft Design %X The next oil crisis will create a new round of interest in alternative energy, renewable sources. The economics of military and commercial sailing will again be hotly debated by naval architects and marine engineers. The difference this time will be the abundance of data from the large world fleet of unmanned air vehicles (UAV), which just might be the key to wind assisted freighters. Our pioneering efforts with recreational kite sailing and buggies have provided part of the database needed to apply UAV technology to the task of wind assist for global transport. This paper will tie the UAV and kitesailing technology to military and commercial needs. For example, the Boeing Condor (Fig 1), with her jumbo jet span and 40,000 lb lift capability, could generate 10,000 lbs of thrust from the trade winds, tethered to a ship at sea. Condor is one of a class of unmanned air vehicle, some with engines and some without, that could be used to extract wind energy to provide up to half of the total motive force for the ships of the world in the 21st Century, thereby conserving billions of barrels of oil, reducing pollution, and improving the quality of life in our ecosystem. Thanks to extensive media coverage in Toyota truck, Levi jean shorts commercials (36) and many other magazines and TV shows, the concept of taming the wind with large traction kites is no longer entirely unknown. %B 56th Annual Conference, Bellevue, Washington, May 19-21 %I Society of Allied Weight Engineers, Inc. %C Bellevue, Washington %P 15 %8 5/19/97 %G eng %U https://www.sawe.org/papers/2399/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 2399 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE2399 %0 Conference Paper %B 55th Annual Conference, Atlanta, Georgia, June 3-5 %D 1996 %T 2316. The CH-47 Inproved Cargo Helicopter (ICH) Program %A McMullan, J C %K 10. Weight Engineering - Aircraft Design %X (None) %B 55th Annual Conference, Atlanta, Georgia, June 3-5 %I Society of Allied Weight Engineers, Inc. %C Atlanta, Georgia %P 23 %8 6/3/96 %G eng %U https://www.sawe.org/papers/2316/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 2316 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE2316 %0 Conference Paper %B 55th Annual Conference, Atlanta, Georgia, June 3-5 %D 1996 %T 2317. Civil Tiltrotor Configuration Development for the 21St Century %A Lacy, R W %A Wilkerson, J B %A Newman, D I %K 10. Weight Engineering - Aircraft Design %X Introduction of a civil tiltrotor into the National Air Transportation System in the early part of the next century continues to be an attractive, economically viable option for reducing growing air traffic congestion problems and improving passenger total travel time. Preliminary configuration definition of a safe, has evolved as system trade studies affordable vehicle are conducted, and integrated into the design. This technical paper will review the CTR2000 configuration development, and system trade studies of emergency power requirement, cabin seat configuration, and engine sizing for Category A takeoff and landing capability. %B 55th Annual Conference, Atlanta, Georgia, June 3-5 %I Society of Allied Weight Engineers, Inc. %C Atlanta, Georgia %P 16 %8 6/3/96 %G eng %U https://www.sawe.org/papers/2317/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 2317 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE2317 %0 Conference Paper %B 55th Annual Conference, Atlanta, Georgia, June 3-5 %D 1996 %T 2330. Aircraft Design for Carrier Operations %A Author, No %K 10. Weight Engineering - Aircraft Design %X (None) %B 55th Annual Conference, Atlanta, Georgia, June 3-5 %I Society of Allied Weight Engineers, Inc. %C Atlanta, Georgia %P 85 %8 6/3/96 %G eng %U https://www.sawe.org/papers/2330/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 2330 %1 Non-Member Price: $42.50; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 42.5 %4 SAWE2330 %0 Conference Paper %B 54th Annual Conference, Huntsville, Alabama, May 22-24 %D 1995 %T 2268. Weight - Cost - Schedule Interactions in Aircraft Rapid Prototyping %A Bennett, Dr. , G %K 10. Weight Engineering - Aircraft Design %X The weight-cost-schedule interactions of several prototype composite aircraft projects conducted at the Raspet Flight Research laboratory are discussed. It has been found that the customer?s definition of the project schedule, funding level, and objectives has a major effect on the weight efficiency of the completed vehicle. The RFRL safety requirements also influence the weight. It has been found that the expertise of the development team is the controlling factor in delivering a project on schedule. Very short schedules limits the configuration optimization which impacts the weight. A brief discussion of a weight_cost_schedule model based on RFRL project experience is given. The impact of CAD-CAM software and large 5 axis routers of RFRL prototype projects is discussed. %B 54th Annual Conference, Huntsville, Alabama, May 22-24 %I Society of Allied Weight Engineers, Inc. %C Huntsville, Alabama %P 15 %8 5/22/95 %G eng %U https://www.sawe.org/papers/2268/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 2268 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE2268 %0 Conference Paper %B 54th Annual Conference, Huntsville, Alabama, May 22-24 %D 1995 %T 2282. Semi-Analytical Method for Predicting Wing Structural Mass %A Macci, S H %K 10. Weight Engineering - Aircraft Design %X Depending on the type of aircraft, the structure accounts for between 20-30% of the gross weight, while the wing contribute about 10% of the total structural mass. It is the portion most directly under the control of the designer. Simple wing mass prediction methods developed and used in general are based on empirical information and weighting factors collected over the years for existing aircraft. These methods only require the most fundamental wing data, i.e., wing span, area, etc. It is therefore difficult to use such methods as design tools to assess the affect of various design parameters on wing mass. Examples of such parameters include planform geometry (wing span, root chord, tip chord, wing thickness, wing sweep, wing area, etc.), design operating conditions, and material characteristics (allowable stresses, elastic and rigidity modulus, etc.). It is also true to say that one cannot fully rely on the answers obtained from such methods. All major aircraft manufacturing companies have developed self relying theoretical/empirical mass prediction methods. It is very difficult to obtain details of these methods, and in any case such methods are often only applicable for aircraft made and designed by these organizations. This paper describes a theoretical mass prediction method developed for use as a general tool for preliminary aircraft design work. Design variables that can be tested include wing geometric parameters, design operating conditions and material properties?allowable stresses can be evaluated from a given loading condition. The theory is based on the premise that the wing structural box must be designed to meet both the bending strength and torsional stiffness requirements. The technique accounts for structures made in both and fiber reinforced plastic (FRP) materials. Preliminary test carried out on a number of aircraft made from metallic materials suggest that the method gives results that are consistent with manufacturers? data. %B 54th Annual Conference, Huntsville, Alabama, May 22-24 %I Society of Allied Weight Engineers, Inc. %C Huntsville, Alabama %P 42 %8 5/22/95 %G eng %U https://www.sawe.org/papers/2282/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 2282 %1 Non-Member Price: $21.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 21 %4 SAWE2282 %0 Conference Paper %B 53rd Annual Conference, Long Beach, California, May 23-25 %D 1994 %T 2187. Weight Control of the Learjet M45 Wing in the Design Build Team/Catia Environment %A Clapp, R P %A Kiskunas, V J %K 10. Weight Engineering - Aircraft Design %X When de Havilland was awarded the contract to design and build the wing for the Learjet M45 Business Jet, it was decided to use Design Build Teams, Concurrent Engineering and CATIA. The acceptance of this design/build philosophy was based on the previous successful completion of a pilot project using these principles. This paper describes the experiences of the Weights Group in this environment. Membership on the Design Build Teams consisted of personnel from most (but not all) of the functional groups within the Company. A Weights Methodology was developed, based on software developed in-house for use with CATIA, so that the Mass Properties of the wing and its component parts could be analyzed. The software also handled special cases such as handed parts and multiple use parts. The use of these techniques resulted in a program which had the required design weight continuously maintained as a high profile item. As a result, the program has been successful in controlling weight growth. The current weight status is 1.6% over the design weight specified by Learjet Inc. %B 53rd Annual Conference, Long Beach, California, May 23-25 %I Society of Allied Weight Engineers, Inc. %C Long Beach, California %P 19 %8 5/23/94 %G eng %U https://www.sawe.org/papers/2187/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 2187 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE2187 %0 Conference Paper %B 53rd Annual Conference, Long Beach, California, May 23-25 %D 1994 %T 2200. STOVL Aircraft Weight Evaluation %A Yackle, A R %K 10. Weight Engineering - Aircraft Design %X Payload capability of a vertical/short takeoff and landing (V/STOL) aircraft depends to a large extent on the operational concept. When a V/STOL is designed primarily for vertical takeoff and landing (VTOL), the aircraft is appreciably larger heavier, and more costly than a carrier based conventional takeoff and landing (CTOL) aircraft even though the VTOL aircraft is no longer required to withstand catapult and arrested loads. However, weight penalties associated with carrier operation can be reduced significantly by operating routinely in a short takeoff and vertical landing (STOVL) mode. The purpose of this paper is to illustrate the use of weight comparisons in evaluating STOVL aircraft concepts. In conceptual design, weight comparisons between aircraft of similar mission performance is one of the more important criteria for selecting a practical concept. Also, weight empty is the primary parameter for estimating costs. A weight evaluation technique is illustrated in this paper by comparing the weight penalties of conventional carrier based CTOL aircraft with the weight penalties of STOVL aircraft. To assist in this comparison, a simplified expression for ""weight growth factor"" is employed. Subjects of this paper are presented in three (:3) parts: 1. History of V/STOL leading toward STOVL is summarized. 2. Existing carrier based CTOL aircraft weight penalty is identified. 3. Weight comparisons of both supersonic and subsonic STOVL aircraft for carrier operation is summarized. %B 53rd Annual Conference, Long Beach, California, May 23-25 %I Society of Allied Weight Engineers, Inc. %C Long Beach, California %P 9 %8 5/23/94 %G eng %U https://www.sawe.org/papers/2200/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 2200 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE2200 %0 Conference Paper %B 53rd Annual Conference, Long Beach, California, May 23-25 %D 1994 %T 2202. Derivation of Aircraft Shear and Bending Diagrams Based on Preliminary Design Inputs %A Lovenguth, M A %K 10. Weight Engineering - Aircraft Design %X The purpose of this paper is to define a method which will allow the calculation of vertical shear and vertical bending moment diagrams using inputs which are commonly available in preliminary design. The scope of the paper is such that not the entire spectrum of aircraft conditions can be evaluated, however, the method will result in the ability to calculate shear and bending along a significant portion of the aircraft length. The method will first be presented as it specifically applies to the V-22 Osprey. Correlation between the method and the V-22 NASTRAN output will be shown. All V-22 data presented in this paper reflects the 1987 Full Scale Development (FSD) aircraft. The method will then be generalized showing the potential application to single rotor or tandem helicopters. %B 53rd Annual Conference, Long Beach, California, May 23-25 %I Society of Allied Weight Engineers, Inc. %C Long Beach, California %P 23 %8 5/23/94 %G eng %U https://www.sawe.org/papers/2202/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 2202 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE2202 %0 Conference Paper %B 53rd Annual Conference, Long Beach, California, May 23-25 %D 1994 %T 2220. Center of Gravity Envelope Development, 747-400F %A Davis, E W %K 10. Weight Engineering - Aircraft Design %X This paper is written to explain the logic behind the development of the gross weight versus CG envelope for the Boeing 747-400F. This paper takes the CG envelope of the 747-400F and attempts to describe the basis for each and every line and each and every intersection in the CG envelope for the 747-400F. This paper was written by a weights engineer for use by other weights engineers at Boeing and at the Airlines. In my position at Boeing, I frequently receive questions from the Airlines asking what causes the CG limits in the Airplane Flight Manual and the Weight and Balance Manual. Hopefully this paper will help address some of these questions and help sort out the combination of history and new design that combine together to formulate the CG envelope for a derivative airplane like the 747-400F. %B 53rd Annual Conference, Long Beach, California, May 23-25 %I Society of Allied Weight Engineers, Inc. %C Long Beach, California %P 63 %8 5/23/94 %G eng %U https://www.sawe.org/papers/2220/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 2220 %1 Non-Member Price: $31.50; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 31.5 %4 SAWE2220 %0 Conference Paper %B 52nd Annual Conference, Biloxi, Mississippi, May 24-26 %D 1993 %T 2165. Stretching an Aircraft - A Case Study: Canadair Regional Jet %A Read, A R %K 10. Weight Engineering - Aircraft Design %X This paper has been prepared to document the weight and balance data derived during the design and development of an aircraft stretch program. The aircraft under discussion is the Canadair Regional Jet, designed and manufactured by Canadair, a group of Bombardier, Inc. The Regional Jet is a stretch of the Challenger Executive Jet, incorporating (among other things) a fuselage plug 20 feet long, thereby increasing the overall length to 80 feet, The Regional Jet is designed to carry 50 passengers 1,650 statute miles at speeds of up to 530 MPH. Current configurations include 56 seat layouts and 18 seat executive passenger layouts. The prime directives stipulated at the beginning of the program were: Minimum Change and Minimum Cost These directives together with a very tight schedule limited the effectiveness (or power) of the weights group to ensure an efficient worthwhile optimization program. It was agreed then, with these directives in mind, that, based on the weight predictions at configuration freeze, a 10% allowance should be added to all new and major change components and that the resultant aircraft weight should be set as the specification weight. This paper describes how successful the 10% allowance was, where the significant increase originated, and during which phase they were induced, together with an overview of the aircraft balance and loadability characteristics. %B 52nd Annual Conference, Biloxi, Mississippi, May 24-26 %I Society of Allied Weight Engineers, Inc. %C Biloxi, Mississippi %P 13 %8 5/24/93 %G eng %U https://www.sawe.org/papers/2165/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 2165 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE2165 %0 Conference Paper %B 52nd Annual Conference, Biloxi, Mississippi, May 24-26 %D 1993 %T 2183. SAVVIE, an Example of Simulation in Prototyping %A Turpin, T S %A McQuillan, F J %K 10. Weight Engineering - Aircraft Design %X The U.S. Army Advanced Systems Research and Analysis Office (ASRAO) has responsibility for the Vertical Take Off and Landing (VTOL) Effectiveness in Combat/Tactical Regimes (VECTR) Project. The objective of the project is to determine the military worth of advanced VTOL platforms. To meet the analysis requirements of the VECTR Project, a high fidelity combat simulation tool has been developed under contract with CAE Electronics Ltd. This tool is the Scenario Analysis for VTOL Vehicles using an Interactive Environment (SAVVIE). This paper describes the software architecture of SAVVIE. It explains the purpose and interface of each of the major modules and details the flexibility which allows the experimenter to specify all attributes of the players and the tactical scenario. It describes how players interact with each other and with the terrain. The final section explains how SAVVIE will be integrated and used in the VECTR analysis process. It discusses the interface of SAVVIE with a manned simulator and involvement of the aviation user community in the wargaming simulations. %B 52nd Annual Conference, Biloxi, Mississippi, May 24-26 %I Society of Allied Weight Engineers, Inc. %C Biloxi, Mississippi %P 15 %8 5/24/93 %G eng %U https://www.sawe.org/papers/2183/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 2183 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE2183 %0 Conference Paper %B 51st Annual Conference, Hartford, Connecticut, May 18-20 %D 1992 %T 2050. The Boeing Model 360 Advanced Technology Demonstrator Helicopter %A Wisniewski, J S %K 10. Weight Engineering - Aircraft Design %X The Model 360 all-composite demonstrator helicopter was developed by Boeing Helicopters over several years. It was company funded by Boeing to validate advanced technologies that could be applied to the company's other rotorcraft programs. Major efforts have been directed at the integration of new technology in structures, aerodynamics, flight controls, avionics and cockpit design. High Strength, lightweight composite materials make up almost all of the aircraft's primary and secondary structure. Four graphite covered rotor blades with tapered tips are attached to a composite rotor hub for increased speed with reduced noise and vibration. A retractable tricycle landing gear and buried aft fuselage engines also improved the aircraft's performance. Pilot's workload is reduced with a digital automatic flight control system and an integrated avionics system. It incorporates a glass enclosed Cockpit with six multi-function displays. The Model 360 Development Program included over 5000 hours of wind tunnel tests and an extensive simulator assessment of the helicopter's handling and flying qualities. First flight of the Model 360 took place on June 10,1987, in suburban Philadelphia. The new helicopter has demonstrated airspeeds at 214 knots and a maximum design speed of 235 knots. The current helicopter world speed record is held -by a Westland Lynx at 214.4 knots. The aircraft is currently in overhaul at the Boeing Helicopters Flight Test Center near Wilmington, Delaware. %B 51st Annual Conference, Hartford, Connecticut, May 18-20 %I Society of Allied Weight Engineers, Inc. %C Hartford, Connnecticut %P 30 %8 5/18/92 %G eng %U https://www.sawe.org/papers/2050/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 2050 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE2050 %0 Conference Paper %B 51st Annual Conference, Hartford, Connecticut, May 18-20 %D 1992 %T 2057. Pratt & Whitney/Nordam 737-200 Hush Kit %A Hutton, J G %K 10. Weight Engineering - Aircraft Design %X Mid 1991, United States Legislation and ICAO rulings were adopted which permit only FAR 36 Stage 3 and ICAO Annex 16, Chapter 3 capable commercial airplanes to operate beyond 1999. This paper begins by demonstrating pressures leading to these laws, the character of the laws as they are understood today, remedial actions, and finally a description of one recourses hush kit for B737-200. The description of the pressures and laws description includes comments concerning typical city airport noise issues. Remedial actions compare alternatives a commercial airplane operator could consider and what is generally available at this time. The 737-200 hush kit presentation includes an historical development documentation of the device, as well as a detailed presentation of the device itself. This paper is an overview only and is intended to provide a general understanding of the issues. %B 51st Annual Conference, Hartford, Connecticut, May 18-20 %I Society of Allied Weight Engineers, Inc. %C Hartford, Connnecticut %P 19 %8 5/18/92 %G eng %U https://www.sawe.org/papers/2057/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 2057 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE2057 %0 Conference Paper %B 51st Annual Conference, Hartford, Connecticut, May 18-20 %D 1992 %T 2104. Summary of Technology Needs for High Speed Rotorcraft %A Scott, M W %K 10. Weight Engineering - Aircraft Design %X An analytical study was conducted to identify rotorcraft concepts best capable of combining a cruise speed of 350 to 450 knots with helicopter-like low speed attributes and to define the technology advancements needed to make them viable for full scale development by the year 2000. A systematic approach was used to compare the relative attributes and required gross weights for a wide range of concepts, resulting in a downselect to the most promising concept/mission pairs. For transport missions, tilt-wing and variable diameter tilt-rotor (VDTR) concepts were found to be superior. For a military scout/attack role, the VDTR was best, although a shrouded rotor concept could provide a highly agile, low observable alternative if its weight empty fraction could be reduced. A design speed of 375 to 425 knots was found to be the maximum desirable for transport missions, with higher speed producing rapidly diminishing benefits in productivity. The key technologies that require advancement to make the tilt-wing and VDTR concepts viable are in the areas of wing and proprotor aerodynamics, efficient structural design, and flight controls. Specific attention needs to be given to proprotor blade geometry optimization, refinement of the geared flap pitch control system, expansion of the speed/descent envelope, and the structural and aerodynamic tradeoffs of wing thickness and forward sweep. For the shrouded rotor, weight reduction is essential, particularly with respect to the mechanism for covering the rotor in cruise. %B 51st Annual Conference, Hartford, Connecticut, May 18-20 %I Society of Allied Weight Engineers, Inc. %C Hartford, Connnecticut %P 28 %8 5/18/92 %G eng %U https://www.sawe.org/papers/2104/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 2104 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE2104 %0 Conference Paper %B 50th Annual Conference, San Diego, California, May 20-22 %D 1991 %T 2038. A USAF Assessment of STOVL Fighter Options %A Hammond, D %A Fredette, R %A Tamplin, G %A Ashby, R %K 10. Weight Engineering - Aircraft Design %X The US Air Force is in the early stages of defining the next generation multi-role fighter. It is anticipated that this aircraft will begin to replace the F-16 in the 2000-2010 time period. Wright Laboratory (WL) is identifying potential technologies that could have a significant impact on this aircraft. Some of these technologies are aimed at improving the operational flexibility of such an aircraft. The addition of short takeoff and vertical landing (STOVL) capability to fighter aircraft is one of these technology options. WL has invested a substantial in-house effort and contracted studies to define the possible attributes of a STOVL fighter and the required technology base. This is being done to give the US Air Force the option of fielding such an aircraft in the 2000-2010 time frame. The in-house study emphasized the air-to-air role of this multi-role fighter by designing to high levels of maneuverability, dry power supersonic cruise, and low observables. Some findings from the Advanced Fighter Technology Integration STOVL (AFTI STOVL) contracted studies are also summarized. %B 50th Annual Conference, San Diego, California, May 20-22 %I Society of Allied Weight Engineers, Inc. %C San Diego, California %P 25 %8 5/20/91 %G eng %U https://www.sawe.org/papers/2038/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 2038 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE2038 %0 Conference Paper %B 49th Annual Conference, Chandler, Arizona, May 14-16 %D 1990 %T 1924. An Aerodynamic and Design Analysis of the Human Powered Helicopter %A Mourtisen, S %K 10. Weight Engineering - Aircraft Design %X This paper outlines some of the considerations and difficulties involved with designing a human powered helicopter (HPH). A discussion of the math models from momentum theory to a lifting line model is given. Physiological considerations such as the relationship between pilot power available and pilot weight are also addressed. Based upon a statistical survey and preliminary computations, it was shown that the best possible design for the HPH satisfying the weight requirements was a biplane rotor system. Assuming the typical design weight for the HPH to be 200 lb. and the power available to be .6 hp, it is shown that the resulting rotor radius is about 75 feet. Assuming a 130 lb. pilot, the empty weight- would be 70 lb. The question is, is it possible to build a 70 lb. empty weight, 75 foot radius helicopter? The conclusion is that by looking at historical data points, a deviation from conventional design is necessary in order to win the AHS contest. The design process reduces to the ability to predict performance and weight accurately. The procedures discussed in the paper culminate in an overall sizing plot for rotor radius which simultaneously predicts feasibility. %B 49th Annual Conference, Chandler, Arizona, May 14-16 %I Society of Allied Weight Engineers, Inc. %C Chandler, Arizona %P 27 %8 5/14/90 %G eng %U https://www.sawe.org/papers/1924/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1924 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1924 %0 Conference Paper %B 49th Annual Conference, Chandler, Arizona, May 14-16 %D 1990 %T 1925. A Study of Human Powered Helicopter in Japan %A Naito, A %K 10. Weight Engineering - Aircraft Design %X This paper centers on some of the more challenging problems faced when designing a human powered helicopter (HPH). Among the problems are the top and bottom dead points encountered when pedaling. Several ways of resolving this problem have been attempted. First would be to use an oval gear, the second would be to use a cam-spring system, and a third would be to use an entirely different drive system using two one-way clutches instead of rotating cranks. Each of these methods effectively eliminates the dead spots. Other problems were touched upon briefly. In conclusion, there is much work yet to be done to achieve a successful HPH design. The first flight of the Da Vinci III on November 12, 1989, was important technically, proving the possibility of the hover flight of a HPH. %B 49th Annual Conference, Chandler, Arizona, May 14-16 %I Society of Allied Weight Engineers, Inc. %C Chandler, Arizona %P 17 %8 5/14/90 %G eng %U https://www.sawe.org/papers/1925/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1925 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1925 %0 Conference Paper %B 49th Annual Conference, Chandler, Arizona, May 14-16 %D 1990 %T 1928. Soviet Helicopter Technology %A Parlier, C A %K 10. Weight Engineering - Aircraft Design %X This presentation was made possible by the recent changes in the Eastern European political atmosphere. The spirit of ""glasnost"" allowed Cap to inspect Soviet helicopters and discuss technology and design in an open atmosphere. Cap was impressed with the Soviet's new attack helicopter (HAVOC) and with the improved status of Soviet helicopter development. U.S. restrictions would not allow Cap to reciprocate to the same extent with U.S. designs. His presentation was highlighted by some excellent slides of the cockpits and external photos of several Soviet helicopters. He discussed some of the survivability features of the aircraft and other design attributes. %B 49th Annual Conference, Chandler, Arizona, May 14-16 %I Society of Allied Weight Engineers, Inc. %C Chandler, Arizona %P -1 %8 5/14/90 %G eng %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1928 %1 Non-Member Price: $0.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %4 SAWE1928 %0 Conference Paper %B 49th Annual Conference, Chandler, Arizona, May 14-16 %D 1990 %T 1934. Myths of Weight Control %A Johnson, F %K 10. Weight Engineering - Aircraft Design %X This technical paper differs from most in that it draws from the personal observations of the author instead of developing conclusions from a body of technical data. Its purpose is to stimulate thought and discussion. What the author has done is to critique techniques of weight control that he has observed in his own company, and in the companies of competitors, team members, and sub-contractors. Most of these techniques have been expressed in public forums, in particular, the Weight Control Session of the Society of Allied Weight Engineers. The subject is generic, has no relationship to a specific airplane model, and in no way represents a policy of his company. %B 49th Annual Conference, Chandler, Arizona, May 14-16 %I Society of Allied Weight Engineers, Inc. %C Chandler, Arizona %P 20 %8 5/14/90 %G eng %U https://www.sawe.org/papers/1934/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1934 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1934 %0 Conference Paper %B 49th Annual Conference, Chandler, Arizona, May 14-16 %D 1990 %T 1967. Application of Experimental Design Methodology to Aircraft Design %A Cregger, S E %K 10. Weight Engineering - Aircraft Design %X During the aircraft design process, engineers are often called upon to make difficult decisions. An incorrect or ill-advised choice on some matters could have dire consequences. During the initial stages of design, for example, choosing an inferior configuration could lead to poor performance, inadequate mission performance capability, and ultimately, the loss of a multi-million dollar contract. Unless the optimum materials are then chosen to build the configuration, the aircraft may suffer weight, performance, cost, manufacturing, and/or maintainability difficulties. Finally, incorrect decisions during the structural design phase may lead to excess weight (i.e., lower performance) or even catastrophic in-flight failures. Unfortunately for the engineer faced with resolving these issues, only a finite amount of money, time, and personnel are available even for solving important problems such as these. Obviously, one solution to this dilemma is to make more efficient use of the available resources. This would allow the engineer to obtain the best possible answers to these important problems within the limits of manpower, schedule, and cost. One tool which will aid in doing this is ""Design of Experiments"" (DOE). ""Design of Experiments"" is defined as a body of knowledge, based on statistical theories, which allows the user to learn more efficiently from experimentation. The value of DOE has already been recognized by the Department of Defense. DOD document 5000.5 1 -G identifies DOE as an integral part of their Total Quality Management initiative for continuous improvement. DOE techniques can be used in a wide range of applications including analytical/computational trade studies, as well as empirical testing. This paper will introduce the topic of DOE methodology and explore its use at three points in the aircraft design process - configuration development, material selection, and structural design. Emphasis will be placed on the advantages offered by these techniques over more traditional approaches. %B 49th Annual Conference, Chandler, Arizona, May 14-16 %I Society of Allied Weight Engineers, Inc. %C Chandler, Arizona %P 21 %8 5/14/90 %G eng %U https://www.sawe.org/papers/1967/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1967 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1967 %0 Conference Paper %B 48th Annual Conference, Alexandria, Virginia, May 22-24 %D 1989 %T 1873. Rotocraft Weight Trends in Light of Structureal Material Characteristics %A Ingalls, C %A Stepniewski, W Z %K 10. Weight Engineering - Aircraft Design %X Variations in the weights of rotorcraft and their components due to advanced materials use are the topics of this study. The impact of new materials on component weights is illustrated by historical weight trends. The influence of structural material characteristics on the relative weight levels of rotorcraft components, the weight effectiveness, for both static and cyclical loadings is reviewed. Cursory expressions are developed to permit estimation of the effect of structural material strength effectiveness values on component weights. Special constraints which could limit possible weight reductions are considered briefly. Advanced structural materials that exhibit superior weight reduction potential are identified. %B 48th Annual Conference, Alexandria, Virginia, May 22-24 %I Society of Allied Weight Engineers, Inc. %C Alexandria, Virginia %P 35 %8 5/22/89 %G eng %U https://www.sawe.org/papers/1873/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1873 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1873 %0 Conference Paper %B 48th Annual Conference, Alexandria, Virginia, May 22-24 %D 1989 %T 1878. The Weight Improvement Process as an Element of Weight Control %A Klink, K %K 10. Weight Engineering - Aircraft Design %X One approach for attaining a successful weight control effort is to center it around a ""high visibility"" weight improvement program. In addition to normal weight performance tracking and reporting, an intensive effort should be initiated early on to solicit weight improvement suggestions. Weight reduction can be accomplished through positive employee motivation and without traditional methods of target weights, monthly goals, crash reduction programs, etc. The Weight Improvement Program (WIP) philosophy is to give praise, challenge requirements, set goals, report progress, and unleash human potential throughout the design process. Positive motivation and the creative energy of every individual on the project is an integral part of the weight control process. %B 48th Annual Conference, Alexandria, Virginia, May 22-24 %I Society of Allied Weight Engineers, Inc. %C Alexandria, Virginia %P 30 %8 5/22/89 %G eng %U https://www.sawe.org/papers/1878/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1878 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1878 %0 Conference Paper %B 48th Annual Conference, Alexandria, Virginia, May 22-24 %D 1989 %T 1914. Weight Penalties for Emc Interference Control %A Carstensen, R V %K 10. Weight Engineering - Aircraft Design %X Electromagnetic compatibility is both a force enabler and a force multiplier. Electromagnetic interference can degrade warfighting capability. Interference energy can be controlled by absorption or reflection of unwanted energy, which can lead to weight penalties. Electronic sensors and processors are used to gain a technological advantage over hostile forces. As a consequence, these systems are used to multiply the effect of our limited combat resources. Full warfighting capability in air weapon systems depends, on the proper functioning of high technology electronic sensors and processors. Adverse electromagnetic environmental effects can degrade the operational effectiveness of these complex electronic systems. Therefore, electromagnetic interference control has become a force enabler which is vital for preserving warfighting capability. The purpose of this paper is to describe the nature of the electromagnetic environment (EME) and those techniques available to control EMI which result in weight penalties for their use. %B 48th Annual Conference, Alexandria, Virginia, May 22-24 %I Society of Allied Weight Engineers, Inc. %C Alexandria, Virginia %P 7 %8 5/22/89 %G eng %U https://www.sawe.org/papers/1914/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1914 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1914 %0 Conference Paper %B 47th Annual Conference, Plymouth, Michigan, May 23-25 %D 1988 %T 1820. A Look at Tomorrow's Civil Tilt Rotor %A Wilkerson, J B %K 10. Weight Engineering - Aircraft Design %X Tiltrotor development has progressed over the past decade from the very successful XV-15 flight demonstrator program to the current V-22 full scale development program. In 1985 a civil tiltrotor study was jointly sponsored by FAA, NASA, and DOD to evaluate and document the potential of the commercial tiltrotor market. The results of that study show that a substantial share of the shorthaul market of the Northeast Corridor can be captured by civil tiltrotor aircraft, assuming that IFR-certified vertiports are available around major hub cities. This paper presents some of the preliminary design effort supporting the study. It shows the engineering aspect of modifying the baseline military V-22 to a civil configuration and examines a larger, all-new, civil tiltrotor design. %B 47th Annual Conference, Plymouth, Michigan, May 23-25 %I Society of Allied Weight Engineers, Inc. %C Plymouth, Michigan %P 26 %8 5/23/88 %G eng %U https://www.sawe.org/papers/1820/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1820 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1820 %0 Conference Paper %B 47th Annual Conference, Plymouth, Michigan, May 23-25 %D 1988 %T 1845. Extending Derivative Airplane Capaabilities; Weight and Balance Considreation %A Williams, B %K 10. Weight Engineering - Aircraft Design %X Loadability plays a large part in defining the limit of thrust and weight growth of derivative aircraft. As gross weight and fuel requirements associated with increasing the payload and range capability go up, structural capability and aerodynamic control limits reduce the allowable center of gravity (C.G.) range available for loading revenue payload. This narrower C.G. range imposes cargo and baggage loading and/or passenger seating restrictions on airline operation. Through selective modification of the critical structural parts of the airplane and use of the gains in aerodynamic capability from increased body length, loadability restrictions can be reduced or eliminated. This paper addresses the general type of loadability limits encountered in defining the C.G. range for a typical wing-engined aircraft, how they are required to change to meet the needs of a derivative, and how the limits change with modifications to the aircraft. %B 47th Annual Conference, Plymouth, Michigan, May 23-25 %I Society of Allied Weight Engineers, Inc. %C Plymouth, Michigan %P 13 %8 5/23/88 %G eng %U https://www.sawe.org/papers/1845/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1845 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1845 %0 Conference Paper %B 47th Annual Conference, Plymouth, Michigan, May 23-25 %D 1988 %T 1848. Beryllium Application and Engineering %A Parsonage, T B %A Dorn, C K %K 10. Weight Engineering - Aircraft Design %X In the design of complex structures, material selection must be based upon a variety of characteristics such as strength, fabricability, and the interaction between materials within the system. When designers select beryllium, it is often as a result of its unique combination of properties which can be more important than the value of any individual property. This paper describes those unique properties and how they relate to the successful use of beryllium in mass and stiffness critical applications. %B 47th Annual Conference, Plymouth, Michigan, May 23-25 %I Society of Allied Weight Engineers, Inc. %C Plymouth, Michigan %P 11 %8 5/23/88 %G eng %U https://www.sawe.org/papers/1848/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1848 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1848 %0 Conference Paper %B 46th Annual Conference, Seattle, Washington, May 18-20 %D 1987 %T 1756. The Criticality of Weight and Balance on Competition Aircraft %A Boland, B C %K 10. Weight Engineering - Aircraft Design %X The intent of this paper is to illustrate proven principles of weight and balance and to demonstrate the sensitivity of a high performance, short-coupled aircraft to weight change and center of gravity (c.g.) movement. In addition, this presentation is intended to give young weight engineers a respite from today's complicated, computer-oriented procedures and provide them with a glimpse at ""hands-on"" application of weight and balance principles. The subject aircraft, tsunami, is an all metal, low wing monoplane designed and built from scratch for the purpose of racing, record setting and research. The airplane three-view and dimensional data are presented in figures 1, and 2, respectively. %B 46th Annual Conference, Seattle, Washington, May 18-20 %I Society of Allied Weight Engineers, Inc. %C Seattle, Washington %P 19 %8 5/18/87 %G eng %U https://www.sawe.org/papers/1756/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1756 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1756 %0 Conference Paper %B 46th Annual Conference, Seattle, Washington, May 18-20 %D 1987 %T 1757. Weight Control in Automated Design Equipment %A Staton, R N %K 10. Weight Engineering - Aircraft Design %X Performing the weight control function in an automated design environment has become a reality as well as a new experience for most Weight Engineers. This paper relates some recent experiences of one Group's efforts in this situation. Several problems have been encountered and are discussed. Current automation efforts in order to provide an adequate weight control program along with some long term planning activities are also summarized. Due to security considerations, specific programs are not identified or discussed. A generic approach is used throughout the paper although some results are given as relative percentage values. The situations described are for one company's product line in their particular design environment. However, if you are involved in a weight control activity on a current aerospace vehicle design program, you should find several areas of common interest. %B 46th Annual Conference, Seattle, Washington, May 18-20 %I Society of Allied Weight Engineers, Inc. %C Seattle, Washington %P 23 %8 5/18/87 %G eng %U https://www.sawe.org/papers/1757/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1757 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1757 %0 Conference Paper %B 46th Annual Conference, Seattle, Washington, May 18-20 %D 1987 %T 1772. The Lockheed HTTB-STOL Performance Features %A Packard, G %K 10. Weight Engineering - Aircraft Design %X The Lockheed C-130 Hercules is truly a remarkable airplane. In continuous production for more than 30 years, over 1800 have been delivered to 55 different nations throughout the world, including over 1000 to various branches of the US government. Basically just a flying truck, they can be used for almost anything, form routine delivery of people or supplies to more exotic missions such as fire fighting and satellite retrieval. Sometime, eventually, a replacement will be needed. So to help prepare for that day, one of these aircraft, an L100-20 (a commercial version with a 100 inch fuselage stretch) was repurchased by Lockheed-Georgia to serve as a testbed for new technology for future airlifters - a High Technology Test Bed (HTTB). One important aspect of this new technology will be Short Take Off and Landing (STOL) performance. A 1500-foot runway length will be a requirement for the next generation of tactical cargo aircraft. This is significantly better than the standard C-130, and substantial changes are required to generate additional lift. Still more changes are required to improve low speed stability and control. This paper defines these changes and gives the performance improvements and associated weight penalties. The HTTB program is extensive, testing a number of other advanced systems unrelated to STOL. A program overview is contained in SAWE Paper No. 1786, by C. M. Campbell. %B 46th Annual Conference, Seattle, Washington, May 18-20 %I Society of Allied Weight Engineers, Inc. %C Seattle, Washington %P 18 %8 5/18/87 %G eng %U https://www.sawe.org/papers/1772/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1772 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1772 %0 Conference Paper %B 46th Annual Conference, Seattle, Washington, May 18-20 %D 1987 %T 1773. Advanced Main Rotor System %A Partida, J B %K 10. Weight Engineering - Aircraft Design %X The McDonnell Douglas Helicopter Company (MDHC) advanced rotor system is fitted onto the existing Model 500 vehicle which employs a bearingless main rotor hub with composite flexbeam, pitchcase, and removable blade. This advanced system is configured with four blades and exceeds the dynamic and performance characteristics of the current five blade system. The blade system flexbeam and pitchcase are constructed to interact, with the use of snubber-dampers, to accommodate flapping, feathering, and lead-lag rotor motions. This paper presents the mass property engineers' contribution in the design and fabrication of the removable blade through the careful management of it mass properties. %B 46th Annual Conference, Seattle, Washington, May 18-20 %I Society of Allied Weight Engineers, Inc. %C Seattle, Washington %P 14 %8 5/18/87 %G eng %U https://www.sawe.org/papers/1773/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1773 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1773 %0 Conference Paper %B 46th Annual Conference, Seattle, Washington, May 18-20 %D 1987 %T 1786. Overview of the Lockheed C-130 High Technology Test Bed Program %A Campbell, C %K 10. Weight Engineering - Aircraft Design %X The High Technology Test Bed (HTTB) Program involves a long-term commitment by Lockheed to provide a flight test aircraft for the development and integration of generic technologies by adding major advanced systems to a C-130 type aircraft. The technology and knowledge gain will be essential for Lockheed's and vendor's proposed future aircraft including: tactical airlifters, fighters and other mission aircraft. This paper deals with modifications to the aircraft and briefly discusses the technologies being investigated by these modifications. %B 46th Annual Conference, Seattle, Washington, May 18-20 %I Society of Allied Weight Engineers, Inc. %C Seattle, Washington %P 29 %8 5/18/87 %G eng %U https://www.sawe.org/papers/1786/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1786 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1786 %0 Conference Paper %B 46th Annual Conference, Seattle, Washington, May 18-20 %D 1987 %T 1798. Economical Technology Application in Commercial Transport Design %A Drake, M L %K 10. Weight Engineering - Aircraft Design %X Technology application in the development of modern commercial aircraft must meet today's stringent test of cost effectiveness. The promise of reduced operating costs made possible with new technologies must be balanced with the reality of the up front costs of acquiring these technologies. Simply stated, an airline's cost of acquiring a technology must not meet or exceed the projected savings. In view of large variations in the world's costs of money (e.g. interest rates), fuel and labor over the past twenty years, any projection of savings carries a risk when compared with the fixed reality of an aircraft's purchase price. Today's operator requires an aircraft that is affordable and will remain that way throughout it's useful life. Initial purchase price and operational expenses must be reasonable. However, in addition, today's transport must incorporate the technology that will prevent it from meeting with a premature obsolescence due to changes in the world's economic condition (e.g. very high fuel costs). In brief, aircraft design today must balance the costs of ownership and operation given any expected world economic condition. This paper will survey a number of aircraft design technologies and examine their appropriateness in view of today's new requirements. %B 46th Annual Conference, Seattle, Washington, May 18-20 %I Society of Allied Weight Engineers, Inc. %C Seattle, Washington %P 16 %8 5/18/87 %G eng %U https://www.sawe.org/papers/1798/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1798 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1798 %0 Conference Paper %B 45th Annual Conference, Williamsburg, Virginia, May 12-14 %D 1986 %T 1695. Weight and Center of Gravity Determination on Ground and Airborne %A Drachenberg, H %K 10. Weight Engineering - Aircraft Design %X Since the early 1960's various On Board Weight and Balance Systems were developed and offered by the equipment industry to satisfy the need for an easy maintainable system which performs reliable and repeatable information of Total Aircraft Weight and Center of Gravity (C.G.) with an adequate accuracy on ground. This presentation will reflect the history and the today's status of Weight and Balance System (WBS) development in the relationship to the experience made by MBB as a partner of Airbus Industries. Problem areas, escpecially on the WBS-sensor side, will be identified and discussed. For specific applications, such as the A310-300 aircraft with a Trim Tank system, the determination of inflight C.G. position and its control became a necessary engineering task. The second part of this presentation describes a system configuration which allows actual inflight C.G. determination, and to control and manipulate the C.G. position using the medium of fuel. %B 45th Annual Conference, Williamsburg, Virginia, May 12-14 %I Society of Allied Weight Engineers, Inc. %C Williamsburg, Virginia %P 36 %8 5/12/86 %G eng %U https://www.sawe.org/papers/1695/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1695 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1695 %0 Conference Paper %B 45th Annual Conference, Williamsburg, Virginia, May 12-14 %D 1986 %T 1725. Principles and Practices for Accurate Load Cell Measurements %A Corliss, J C %K 10. Weight Engineering - Aircraft Design %X Strain gage load cell systems can under ideal conditions produce weighings with accuracy as good as +/-.05% of the full scale indication. Less than ideal conditions can easily degrade that performance. This paper will describe those factors which tend to degrade load cell performance and the common practices which have been developed to enhance load cell accuracy. Specifically, the following points will be discussed. 1. Physical Arrangement - Side loading can seriously alter loadcell performance. The merit of tension loading and the use of good flextures will be discussed. For the benefit of those applications in which compression loading is inescapable, the preferred arrangements for compression loading will also be presented. 2. Internal Workings - There is a wide range of quality in loadcells. This quality is usually described in terms like linearity, hysteresis, temperature compensation, repeatability etc. The specific meaning and relevance of these qualities will be discussed and related to the physical characteristics which cause them. 3. Electronic System - Strain gage load cells all require a voltage ratio indicating system. The measurement of the voltage ratio is subject to several subtle effects which can seriously alter the indicated output. Some of these effects will be discussed and related to loadcell accuracy. The qualities of various types of indication systems will also be discussed. The paper will be arranged in an instructive format and will make liberal use of charts, diagrams and sketches. The intention will be to show how loadcell weighing systems, if properly used, can produce convenient and dependable force and mass measurement, when accuracy on the order of +/-.05% is required. %B 45th Annual Conference, Williamsburg, Virginia, May 12-14 %I Society of Allied Weight Engineers, Inc. %C Williamsburg, Virginia %P 14 %8 5/12/86 %G eng %U https://www.sawe.org/papers/1725/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1725 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1725 %0 Conference Paper %B 44th Annual Conference, Arlington, Texas, May 20-22 %D 1985 %T 1669. Requirements for Second Generation Aircraft Weighing Systems %A Ursee, C R %A Wilbur, R L %K 10. Weight Engineering - Aircraft Design %X Weighing of aircraft to determine weights, distribution and center of gravity is becoming more and more a critical and necessary operation. In order to achieve the desired goals, ten basic requirements have been set forth for the second generation of new weighing systems. These requirements involve accuracy, repeatability, linearity, simplicity, portability, ruggedness, size/weight, maintainability, calibration and temperature correction. These have been achieved in two prototype systems that have been in operation for the past five years. %B 44th Annual Conference, Arlington, Texas, May 20-22 %I Society of Allied Weight Engineers, Inc. %C Arlington, Texas %P 6 %8 5/20/85 %G eng %U https://www.sawe.org/papers/1669/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1669 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1669 %0 Conference Paper %B 43rd Annual Conference, Atlanta, Georgia, May 21-23 %D 1984 %T 1597. In-Production Aircraft Weight Control %A Bayly, A D G %K 10. Weight Engineering - Aircraft Design %X Lockheed's history of antisubmarine warfare (ASW) aircraft goes back many years to the PV-1 Ventura and then later the PV-2 Harpoon and P2V Neptune. Advancement in the state-of-the-art of ASW equipment led to the development of the P-3 Orion in the early 1960s. Since its introduction as the P-3A in 1961, the airplane has developed into the present-day design as the P-3C Update III currently being delivered to the Navy. The long life of the P-3 lends itself as a good example of how a successful production weight control program can extend the life of an airplane. This paper provides a history of P-3 weight growth and details the types of changes which cause it. An explanation of how a production weight control program is implemented also is given. Details of a timely weight reduction program that enabled the aircraft to continue to meet its mission requirements are provided. Investigation is made in to the types of weight reduction items that were approved and what ingredients go into making a successful weight reduction program. The paper concludes with the benefits of a good weight control program to an in-production airplane. %B 43rd Annual Conference, Atlanta, Georgia, May 21-23 %I Society of Allied Weight Engineers, Inc. %C Atlanta, Georgia %P 16 %8 5/21/84 %G eng %U https://www.sawe.org/papers/1597/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1597 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1597 %0 Conference Paper %B 43rd Annual Conference, Atlanta, Georgia, May 21-23 %D 1984 %T 1615. Wing Aspect Ratio Optimization Related to Payload and to Fuel Consumption of Transport Propeller Airplanes %A Gili, P A %A Quagliotis, F B %K 10. Weight Engineering - Aircraft Design %X In the preliminary design phase of a new airplane it is very useful to search for the best values of the wing aspect ratio in order to obtain the maximum payload, or the minimum fuel consumption: the wing aspect ratio influences directly the wing weight and obviously, the wing weight decreases, the range and the payload increase, for a fixed total weight. In the paper, solutions are given relating the range, the payload, and the fuel consumption of a propeller airplane, as a function of the aspect ratio and of the flight attitude in the look of an optimization. To this aim a very simple but reliable formula for predicting the wing weight is proposed and introduced in the flight performance equations, which are expressed versus the wing aspect ratio only. In this way, many design solutions can be briefly analyzed in a large operational field. Results allow one to draw diagrams displaying the relation between payload or fuel consumption and flight attitude, for optimum values of aspect ratio at different operational ranges. These plots are useful in the preliminary design stage in order to define the geometry of the airplane, when operational ranges, load capability economical performance have been already given. They also are of help to customers for choosing the more fit airplane for their requirements. %B 43rd Annual Conference, Atlanta, Georgia, May 21-23 %I Society of Allied Weight Engineers, Inc. %C Atlanta, Georgia %P 22 %8 5/21/84 %G eng %U https://www.sawe.org/papers/1615/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1615 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1615 %0 Conference Paper %B 42nd Annual Conference, Anaheim, California, May 23-25 %D 1983 %T 1518. Unique Weight and Balance Aspects of V/STOL Airplane Design %A Graham, T J %K 10. Weight Engineering - Aircraft Design %X This paper is directed to supersonic Fighter/Attack airplanes designed to Navy requirements and ground rules. It deals entirely with Lift/Cruise (vectored thrust) propulsion systems. Vertical/ Short Takeoff and Landing (V/STOL) airplane design presents many design considerations different from those of Conventional Takeoff and Landing (CTOL) airplanes. Weight and balance differences between V/STOL and CTOL will be discussed; but no attempt will be made to evaluate any weight or performance penalties between the two concepts. Some of the considerations which affect weight are larger, heavier propulsion systems for V/STOL. To develop the thrust required to reach supersonic speeds, the engines must further grow in size and weight. The alternative to this is to augment the thrust of today V/STOL engine. Burning the fan bypass air can achieve significant thrust increases without increasing engine size and add a relatively small weight penalty to incorporate burners in the cold air nozzles. This augmentation process is known as Fan Stream Burning (FSB). An additional flight control system is required for vertical flight in the vectored thrust design. Vertical or other landings eliminate catapult, arresting and high lift device requirements. Lower sink rates reduce landing gear structure weight; and brake weight is reduced because of slower landing speeds. A major consideration in the V/STOL design is the vertical thrust center. The vertical thrust center must react through the airplane c.g. during the vertical flight mode. Particular attention is given to alignment of the vertical thrust center with airplane center of gravity, with consideration being given to optimum stability margins relative to the airplane neutral point. These factors dictate engine location relative to the wing. It is therefore imperative that accurate center of gravity envelopes be designed to fit both the vertical mode and the normal flight control envelope. Because of this the weight engineer exerts a strong influence on the airplane design from the initial configuration layout to completion of the flight article. %B 42nd Annual Conference, Anaheim, California, May 23-25 %I Society of Allied Weight Engineers, Inc. %C Anaheim, California %P 16 %8 5/23/83 %G eng %U https://www.sawe.org/papers/1518/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1518 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1518 %0 Conference Paper %B 42nd Annual Conference, Anaheim, California, May 23-25 %D 1983 %T 1567. Impact of MIL-STD-1290 Crash Worthiness Requirements on Design of Helicopter Composite Structures %A Kronkhite, J D %K 10. Weight Engineering - Aircraft Design %X This paper describes the results of a research program to investigate the impact of the U.S. Army's MIL-STD-1290 crashworthiness requirements on the design of helicopter airframes constructed of composite (fiber-reinforced plastic) materials. The program included design, fabrication, and crash testing of two full-scale composite helicopter cabin sections. The cabin sections were derived from the Bell Helicopter Textron, Inc. (BHTI) preliminary design for the Army's Advanced Composite Airframe Program (ACAP). Tests of key energy-absorbing components along with dynamic analysis using the KRASH computer program were utilized in the design of the composite cabin structures. The crash test conditions for the two cabin sections were representative of the 42 ft/sec vertical crash impact velocity requirement specified in MIL-STD-1290, assuming the landing gear had slowed the aircraft from 42 ft/sec to 30 ft/sec prior to fuselage contact. Roll attitudes of 0° (flat) and 20° were used in the two cabin drop tests. Test results from both drop tests indicated that the strong protective shell structure around the occupants remained intact; structural deformation was restricted to the areas designed to crush and absorb energy; and most important, the excellent post-test condition of the cabin protective shell structure and the performance of specially designed energy-absorbing components demonstrated that the Army's crashworthiness requirement could be met by a composite structure. %B 42nd Annual Conference, Anaheim, California, May 23-25 %I Society of Allied Weight Engineers, Inc. %C Anaheim, California %P 26 %8 5/23/83 %G eng %U https://www.sawe.org/papers/1567/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1567 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1567 %0 Conference Paper %B 42nd Annual Conference, Anaheim, California, May 23-25 %D 1983 %T 1570. Boeing 757-200 - Development and the Contibution of Weight and Balance Control %A McIntosh, I M %K 10. Weight Engineering - Aircraft Design %X In the mid-l970s, the projected economic and environmental outlook for the airlines was bleak. Many existing airplanes would soon cease to be cost effective due to rising fuel costs and would be unable to comply with proposed regulations governing community noise. The requirements could only be satisfied with a new airplane that exploited the latest improvements in airfoil design, propulsion, materials, and avionics. The Boeing Company, with its proven capabilities, was well postured to meet this challenge and took the initiative to provide the airlines with a superior product at the right time. The Boeing 757-200 program was announced in August of 1978, following a 30-month period of preliminary design studies. A full production go-ahead was given in March 1979, and certification was obtained in December 1982. The 757-200 is a twin engine, standard body, short-to-medium range airplane employing state-of-the art technology. It is the newest member of the Boeing family of new technology airplanes. As a stablemate of the 767, it is designed for energy conservation, reduced noise levels, and operational flexibility. This paper provides an overview of the 757-200 configuration development and highlights some of the design characteristics. Improvements relative to the 727-200 are illustrated. The substantial contribution made by the weight control/improvement program is discussed. In order to provide the most weight efficient design, an aggressive, highly visible, weight control/improvement plan was developed and implemented in the early stages of the design. The outstanding success of the Weight Improvement Program permitted the specification weight to be reduced dramatically during the development phase of the airplane. It also provided improvements in airplane manufacturing costs. The level of success was due, in large part, to the high degree of management support and commitment and the team spirit and participation that prevailed throughout the program. The results made a major contribution to surpassing the original airplane design objectives. This paper also includes a discussion of the procedures used to develop the airplane center of gravity limits. Rigorous attention to balance and loading during airplane development resulted in the airplane exhibiting excellent loading characteristics for a wide range of interior configurations. Example loading characteristics are presented. %B 42nd Annual Conference, Anaheim, California, May 23-25 %I Society of Allied Weight Engineers, Inc. %C Anaheim, California %P 21 %8 5/23/83 %G eng %U https://www.sawe.org/papers/1570/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1570 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1570 %0 Conference Paper %B 41st Annual Conference, San Jose, California, May 17-19 %D 1982 %T 1453. Advanced Propfan Testbed - ""A Progress Report"" %A Warnock, W E %K 10. Weight Engineering - Aircraft Design %X During the 1960's the rapid advance of high subsonic speed cruise technology, the abundance of relatively expensive fuel, together with the simplicity of the turbojet and turbofan caused a trend away from propellers because of the low efficiency at high subsonic speed. In recent years the escalation of fuel prices and occasional shortages have demonstrated the need for improved propulsive efficiency at high subsonic speeds, which in turn , has created renewed interest in propeller technology. Modern commercial passenger transports cruise at altitudes of 30,000 feet and above at Mach numbers in excess of 0.8. Analysis and tests of the advanced turboprop propulsion system - "Prop-Fan" - have shown that at these conditions, the propfan can operate efficiently w i t h fuel savings relative to turbofans of 20 to 35 percent. As fuel costs continue to become a more significant portion of the Direct Operating Costs (DOC) th,e savings can result in DoC reductions of 5 to 10 percent. Experimental work performed so far has used prop-fan models 24.5 in. in diameter. To enhance industry acceptance of the concept and to resolve questions and issues related to prop-fan technology readiness, large-scale tests are needed before design commitment to prop-fan propulsion can be approached with confidence. Since the high-speed cruise environment is difficult to simulate for large-scale propellers, a f light test program using prop-fan drive systems installed on a test bed aircraft is a necessary adjunct to the completed, current, and planned scale-model tests. The purposes of the investigation from which this paper is taken were to: • Identify those high-speed turboprop technology questions and issues best addressed through test of large-scale prop-fans i n the realistic flow field of a test bed aircraft installation and to establish the testbed program objectives and priorities. • Identify propeller drive systems and aircraft combinations that best accomplish the objectives. • Evaluate, recommend, and perform conceptual designs of two such system. • Generate a test bed program cost and schedule for both systems. • Establish a wind tunnel test program plan for the test of the propeller and drive system. This paper will deal primarily with the second and third task. %B 41st Annual Conference, San Jose, California, May 17-19 %I Society of Allied Weight Engineers, Inc. %C San Jose, California %P 27 %8 5/17/82 %G eng %U https://www.sawe.org/papers/1453/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1453 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1453 %0 Conference Paper %B 41st Annual Conference, San Jose, California, May 17-19 %D 1982 %T 1454. Grumman's Forward Swept Wing Feasibility Studies and X-29A Technology Demonstrator %A Raha, J E %K 10. Weight Engineering - Aircraft Design %X Although employed occasionally in the past for aerodynamic and configuration purposes, the advantages of forward wing sweep have not been exploited up until now because of the potential for structural divergence. Advanced composite materials have opened the door to the use of forward swept wings in modern combat aircraft without excessive weight penalties. Grumman’s X-29A Technology demonstrator program will lead to a 1984 first flight of an aircraft incorporating forward weep and other advanced technologies. %B 41st Annual Conference, San Jose, California, May 17-19 %I Society of Allied Weight Engineers, Inc. %C San Jose, California %P 14 %8 5/17/82 %G eng %U https://www.sawe.org/papers/1454/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1454 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1454 %0 Conference Paper %B 41st Annual Conference, San Jose, California, May 17-19 %D 1982 %T 1467. An Introduction to the Boeing 767-200 and the 767 Weight Control Program %A Griffiths, J %K 10. Weight Engineering - Aircraft Design %X This paper provides an introduction to the Boeing 767-200 and describes the 767 Weight Control Plan. The 767-200 is a medium range , twin engine, commercial transport aircraft designed to carry 211 passengers at ranges up to 2,845 nautical miles with substantially better fuel efficiency than previous generation aircraft. The first part of the paper gives an overview of the 767-200, highlighting major design features, weights, and performance. The remainder of the paper is devoted to the 767 Weight Control Plan, which is regarded as one of the outstanding engineering successes of the 767 Program. The plan is centered around a “design package team” concept to establish accurate weight estimates early in the Program and to set target weight consistent with the overall aircraft weight guarantees. Cost/Weight guide lines are established to assist in making weight change decisions and the progress of each design team toward meeting its weight goals is monitored through a formal tracking procedure. A weight reduction system is put into effect to solicit, evaluate, approve, and incorporate weight improvement ideas. The success of the 767 Weight Control Plan can be measured by the fact that the status weight varied by less than plus or minus one half of one percent from go-ahead through actual weighing with the actual weight of the airplane of record within 400 lb of that predicted at go-ahead. %B 41st Annual Conference, San Jose, California, May 17-19 %I Society of Allied Weight Engineers, Inc. %C San Jose, California %P 30 %8 5/17/82 %G eng %U https://www.sawe.org/papers/1467/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1467 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1467 %0 Conference Paper %B 41st Annual Conference, San Jose, California, May 17-19 %D 1982 %T 1468. Optimization of Fire Blocking Layers for Aircraft Seating %A Parker, J A %A Kourtides, D A %K 10. Weight Engineering - Aircraft Design %X The use of ablative materials in various forms, such as cellular structures, coating and films to provide thermal protection for heat sensitive substrates against the action of large jet fuel fires is well established (1). Low density foam polymers with low thermal conductivity, high temperature stability and high thermo chemical char yields or high transpirational cooling rates, such as those foam fabricated from isocyanurates, phenolics, imides and hydrated chlorprenes, all have been found to be effective in extend the times required for fuel tank cook off and fire penetration to the structures of transport aircraft immersed in large fuel fires. Char forming ablative coatings, are widely used in extending the time before detonation of military ordinance exposed to similar fire threats. The use of functional fabrics as ablatives is new. Among existing, commercial polymers, one would be hard pressed to find a more thermally sensitive substrate than conventional flexible polyurethane foams, and probably from a mechanical point of view no better cushioning material with a cost of something like $ 0.15 per board foot . These polymers because of their easily pyrolyzed urethane groups and thermally oxidizable aliphatic linkages exhibit polymer decomposition temperatures of the order of 250"C, and encounter a maximum pyrolysis rate at 300°C with a total yield of pyrolysis vapor of about 95%, most of which is combustible. One should expect these materials to ignite easily with low power energy sources of 2.5 watts/cm2 or less and when ignited effects sustained flame propagation even after removal of heat source. To be sure all non-fire retarded flexible urethane foams that we have examined to date confirm these expectations. From thermogravimetric studies (2), it is evident that the addition of standard fire retardant additives have little or no effect on the maximum decomposition rate, the temperature at which it occurs or the vapor production yield. In fact, one observes the same average mass injection rates of combustible gases under a sustained radiant heating rate from f lexible polyurethane foams whether fire retarded or not. This gas production rate can amount to as much as 10-20x10-5 Grams/cm2/sec at heating rates of 2.5 watts/cm2 even when covered with contemporary upholstery. Kourtides has shown that this flammable gas production rate increase almost linearly with the applied heating rate up to about 6 watt/cm2, heating rates which are fairly typical of a usual trash or jet fuel fire. A value of 4x10-4 grams/cm2/sec for hydrocarbon injection as surfaces has been found to effect sustained propagation and flame spread. A sustained heating rate of approximately 5 watts/cm2 applied to one seat of a three seat transport array comprising flexible polyurethane foam, fire retarded or not will produce flame spreading and ignition to the adjacent seat in less than one minute, resulting in sufficient fire growth to permit flames to impinge on the aircraft ceiling in less than two minutes. This time required to produce these events and the resulting increases in cabin air temperatures should be expected to fix the allowable egress times fore passengers attempting to escape the aircraft in a post crash fuel fire. This paper then examines the question of the possibility of increasing the available egress time for passengers, from a transport aircraft, in which the flexible polyurethane seating is exposed to the action of a large pool fire which we must assume can provide at least 5 watts/cm2 radian heat flux to the seats, by providing sufficient ablative protection for polyurethane cushioning. These fire blocking layers must suppress the combustible mass injection rates of the polyurethane below the somewhat critical values of 4x10-4 grams/cm2/sec at 5 watts/cm2 as a performance criteria to prevent flame spread and subsequently flash over. %B 41st Annual Conference, San Jose, California, May 17-19 %I Society of Allied Weight Engineers, Inc. %C San Jose, California %P 25 %8 5/17/82 %G eng %U https://www.sawe.org/papers/1468/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1468 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1468 %0 Conference Paper %B 41st Annual Conference, San Jose, California, May 17-19 %D 1982 %T 1499. V/STOL; STOL; CTOL Comparisons %A Priestley, R T %A Yackle, A R %K 10. Weight Engineering - Aircraft Design %X Multi-mission, CTOL, STOL and V/STOL aircraft concepts were sized for the Navy ASW/ASUW missions and comparatively evaluated. Initially, technology levels in the areas of lift, control systems, propulsion, advanced materials and avionics were established for the early 1990's The aircraft were compared to determine the impact of multi-mission requirements, operational considerations, chiefly takeoff mode, as well as the technology advancements. Results presented include performance envelopes, weight statements, growth factor, impact of technology on weight reduction and the impact of design constraints. %B 41st Annual Conference, San Jose, California, May 17-19 %I Society of Allied Weight Engineers, Inc. %C San Jose, California %P 10 %8 5/17/82 %G eng %U https://www.sawe.org/papers/1499/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1499 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1499 %0 Conference Paper %B 41st Annual Conference, San Jose, California, May 17-19 %D 1982 %T 1501. The Impact of Missions on the Preliminary Design of an ABC Rotor %A Desimone, G %A Blauch, R S %K 10. Weight Engineering - Aircraft Design %X Over the years, the results of the XH-59A ABC technology demonstrator aircraft flight test program have been used to generate a series of advanced design solutions to meet a wide variety of mission requirements. These solutions span the entire design spectrum from aircraft designed for high speed cruise to those designed for low speed nap-of-the-earth (NOE) requirements. These studies clearly show the attractiveness of the ABC for these roles, not only in terms of weight and performance but also in terms of compatibility with operations from restricted areas, low external noise, superior agility, and enhanced battlefield survivability and maintainability. It is the purpose of this paper to report on the results of two of these studies with a view towards showing how the preliminary design of the ABC rotor system is affected by mission requirements. The influence that these varying mission requirements have on the selection of critical rotor design parameters of airfoil, twist, taper, radius, chord and tip speed are discussed, and their effects on weight and performance evaluated. In addition, details of the resulting aircraft configurations are presented. %B 41st Annual Conference, San Jose, California, May 17-19 %I Society of Allied Weight Engineers, Inc. %C San Jose, California %P 19 %8 5/17/82 %G eng %U https://www.sawe.org/papers/1501/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1501 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1501 %0 Conference Paper %B 40th Annual Conference, Dayton, Ohio, May 4-7 %D 1981 %T 1407. Fuel - Efficient Air Travel for the 1980's %A Jenson, R %K 10. Weight Engineering - Aircraft Design %X Rapidly increasing fuel costs have resulted in flight crew layoffs and retirement of fuel-inefficient aircraft as the airlines strive to remain profitable. The traveling public is faced with fewer flights, many sold out weeks in advance, and higher fares. To remain economically viable, the fuel efficiency of transport aircraft must be continually improved. Advances in aircraft configuration, materials, propulsion, systems and operations are reviewed to obtain estimates of the potential reduction in fuel usage. Estimated fuel usage for advanced turbofan- and propfan-powered aircraft are compared to a late 1960s design to show the effects of improved fuel efficiency. For the advanced propfan, the fuel consumption per seat nautical mile can be less than one-half that of current wide-body aircraft. %B 40th Annual Conference, Dayton, Ohio, May 4-7 %I Society of Allied Weight Engineers, Inc. %C Dayton, Ohio %P 25 %8 5/4/81 %G eng %U https://www.sawe.org/papers/1407/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1407 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1407 %0 Conference Paper %B 40th Annual Conference, Dayton, Ohio, May 4-7 %D 1981 %T 1432. Potential Benefits of Integrated Active Controls Systems for Current Technology Commercial Transports %A Brown, J D %A Thomas, C J %K 10. Weight Engineering - Aircraft Design %K Mike Hackney Best Paper Award %X

This paper summarizes the definition of five current technology commercial transport airplanes with integrated active controls systems. Their potential performance and economic improvements relative to a Conventional Baseline Airplane are presented. Weight assessments of active controls functions, a summary of the wing structure detailed weight analysis,and center-of-gravity management (balance and loadabi1ity) data are also discussed. *This paper reports work accomplished under NASA contracts NAS1-14742 and NAS1-15325. Acknowledgment is made to Robert H. Brunelle, Albert E. Chukitus, Keith H. Hartz, Robert A. McManus, and the IAAC Design Team, who provided data and guidance.

%B 40th Annual Conference, Dayton, Ohio, May 4-7 %I Society of Allied Weight Engineers, Inc. %C Dayton, Ohio %P 55 %8 5/4/81 %G eng %U https://www.sawe.org/papers/1432/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1432 %1 Non-Member Price: $27.50; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 27.5 %4 SAWE1432 %0 Conference Paper %B 39th Annual Conference, St. Louis, Missouri, May 12-14 %D 1980 %T 1340. Design Considerations for Future Turboprop Transports %A Marsh, D P %K 10. Weight Engineering - Aircraft Design %X Industry, under the sponsorship of NASA’s aircraft energy efficiency (ACEE) program, is taking a serious look at a new generation of propfan-driven passenger aircraft. Some preliminary design studies have been completed and a flight demonstrator program is being planned. This paper reviews the status and results of studies which are being performed at McDonnell Douglas toward defining a viable new generation of turboprop transports. The results of a study of a propfan-equipped DC-9 Super 80 show that a savings in average fuel burned per nautical mile of at least 20 percent may be realized for a near-term Mach 0.8 design turboprop. %B 39th Annual Conference, St. Louis, Missouri, May 12-14 %I Society of Allied Weight Engineers, Inc. %C St. Louis, Missouri %P 8 %8 5/12/80 %G eng %U https://www.sawe.org/papers/1340/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1340 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1340 %0 Conference Paper %B 39th Annual Conference, St. Louis, Missouri, May 12-14 %D 1980 %T 1342. Liquid Hydrogen Fueled Transport Aircraft %A Brewer, G D %K 10. Weight Engineering - Aircraft Design %X The world's supply of petroleum will ultimately be depleted. Most recent estimates by industry experts indicate the peak of crude oil production will be reached in the 1990-2000 decade, possibly as early as 1985. It is timely that positive, aggressive action be initiated to develop information needed to select a fuel for future use in transport aircraft. The choice should be made in full recognition of all the economic, sociological, and technological ramifications, which will be involved. Particularly, global aspects need to be considered. Local advantages or short-term benefits, which might require another change within a few decades, should not be allowed to dominate the considerations. On the basis of conceptual design studies and theoretical analyses liquid hydrogen has been shown to be a very attractive candidate. However, experimental data and operational experience are required to determine its practicability as a fuel for transport aircraft. A comprehensive program has been proposed which will develop technology needed to manufacture and liquefy hydrogen efficiently, and to use it effectively in aircraft. In addition, a study to determine an acceptable type of demonstration program to provide operational experience with LH2-fueled transport aircraft is to be made. The proposed program will provide technical data needed to properly evaluate liquid hydrogen relative to other candidate fuels. Of equal importance, it will also serve to inform and persuade the general public of the many outstanding advantages to be gained through its use, and to establish a basis for public confidence in its safety. Phase One is a three-year R and D effort, which will cost a total of $73.6 million. It is proposed that it be cooperatively funded by several nations under the aegis of the International Energy Agency. %B 39th Annual Conference, St. Louis, Missouri, May 12-14 %I Society of Allied Weight Engineers, Inc. %C St. Louis, Missouri %P 24 %8 5/12/80 %G eng %U https://www.sawe.org/papers/1342/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1342 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1342 %0 Conference Paper %B 39th Annual Conference, St. Louis, Missouri, May 12-14 %D 1980 %T 1343. Flatbed - The Universal Transport Airplane %A Warnock, W E %K 10. Weight Engineering - Aircraft Design %X Flatbed is a Lockheed-Georgia derived configurational concept featuring a wide variety of payloads, which are carried on an open cargo floor. Flatbed can haul containers, passengers in a removable module, cargo or vehicles. Large vehicles and similar outsized payloads are carried in the open. This aircraft offers the potential to reduce costs, provide a solution to the CRAF problem, and reduce the number of different airplane types now required by differing payloads. A Lockheed proprietary concept, Flatbed consists of a basic structure containing the cockpit, wings, engines and empennage. An open, flat section on which the payload is placed connects the cockpit and empennage portions. The payload thus forms, in most cases, the fuselage shape. %B 39th Annual Conference, St. Louis, Missouri, May 12-14 %I Society of Allied Weight Engineers, Inc. %C St. Louis, Missouri %P 21 %8 5/12/80 %G eng %U https://www.sawe.org/papers/1343/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1343 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1343 %0 Conference Paper %B 39th Annual Conference, St. Louis, Missouri, May 12-14 %D 1980 %T 1384. CH-53E Combat Survivability Assessment and Survivability Enhancement Program %A Morrow, J J %K 10. Weight Engineering - Aircraft Design %X This paper presents the results of two sequential programs directed towards the definition of an optimized helicopter configuration in which combat survivability is considered as a major criterion in evaluating the overall effectiveness of the helicopter. The first program was the assessment of the helicopter to determine the configuration, subsystem and component characteristics and features that would result in potential attrition when exposed to hostile weapons. The second program was a tradeoff study to quantify and rank combat survivability enhancement concepts and develop a set of design change recommendations for action by the Program Manager. In general, survivability enhancement results in penalties in the form of increased weight, cost, complexity, maintenance or other factors that impact the life cycle cost of the system. For a helicopter, as for any other vertical lift aircraft, weight is extremely critical. Net thrust is fixed by the propulsion system and any increases in the empty weight of the helicopter must come out of either payload or fuel. For this reason, weight was the driving parameter in this program and the recommended configuration changes are ones that result in high ratios of vulnerability reduction to incremental weight increase. The paper traces the processes and procedures used in both the survivability assessment and the tradeoff study. It also illustrates several light weight survivability enhancement concepts and emphasizes the point that survivabi1iy enhancement is far beyond the heavy, brute force approach of armor application for most of the critical systems of the helicopter. %B 39th Annual Conference, St. Louis, Missouri, May 12-14 %I Society of Allied Weight Engineers, Inc. %C St. Louis, Missouri %P 25 %8 5/12/80 %G eng %U https://www.sawe.org/papers/1384/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1384 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1384 %0 Conference Paper %B 38th Annual Conference, New York, New York, May 7-9 %D 1979 %T 1270. Application of RCS Guidelines to Weight Effective Aircraft Design %A Irish, L A %A Vincent, Dr. , M C %K 10. Weight Engineering - Aircraft Design %X The effectiveness of a military aircraft is a function of a number of characteristics, such as speed, maneuverability, range/payload combinations, weapons carried, electronic countermeasures, and visibility to the enemy's detection systems. In the aircraft design sequence, the emphasis during the early phases tends to be on the trades among familiar performance characteristics such as the first three above, with the others, including the radar cross-section (RCS), being progressively addressed later as the design is refined and detailed. One consequence of this sequence is an appreciable weight penalty due to design measures necessary for control of RCS. A lighter, lower-cost aircraft would result if all these characteristics were considered from the beginning, for two reasons; a more nearly optimum balance would be achieved among the characteristics affecting aircraft effectiveness, and design choices would be made which help to control RCS without appreciably degrading aero performance. The problem is the lack of an organized, proven body of trade data and guidelines on the relationship of RCS to the familiar aircraft design parameters. This paper describes an effort aimed at supplying that need. In a complete description of an aircraft design, there are a multitude of parameters, ranging from gross characteristics such as type of wing planfom or engine location, through basic trade parameters such as wing sweep, wing area, or tail cant, to design details such as antenna type or surface discontinuities around access doors. Fortunately, no one of these parameters is extremely critical for both aero performance and RCS. Hence, armed with adequate knowledge, the designer can choose parametric values which yield the optimum RCS with minimal weight impact either through the direct effect of added treatment material or indirectly through aero performance degradation. %B 38th Annual Conference, New York, New York, May 7-9 %I Society of Allied Weight Engineers, Inc. %C New York, New York %P 9 %8 5/7/79 %G eng %U https://www.sawe.org/papers/1270/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1270 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1270 %0 Conference Paper %B 38th Annual Conference, New York, New York, May 7-9 %D 1979 %T 1273. Tilt Rotor - An Effective V/STOL Concept %A DeTore, J %K 10. Weight Engineering - Aircraft Design %X The objective of this paper is to answer the following questions: • Where does the tilt-rotor aircraft fit in the spectrum of subsonic V/STOL concepts? • What is a mission-oriented tilt-rotor aircraft like; how does it work? • Why is the tilt-rotor V/STOL an effective concept; what can it do? • How can an effective concept be turned into an effective operational system? The approach used includes the following steps: 1) review the variation of hover efficiency, speed capability, and previously determined weight empty ratios for the helicopter, coaxial compound helicopter, the tilt-rotor, tilt wing, lift/cruise fan, and vectored thrust concepts to gain perspective, 2) describe a tilt-rotor design aimed at satisfying Navy/Marine subsonic V/STOL needs, 3) present the projected capabilities of this design to indicate the operational flexibility and efficiency that can be expected, and 4) describe examples of weight-oriented trade-off criteria that can be used to insure selection of effective technology for an operational system. The results presented relate estimated performance capabilities during various modes of flight with useful mission elements. Flight modes include: hover, helicopter and conversion, airplane loiter, high speed and high altitude cruise, and short takeoff runs at overload weights. Mission elements include: search and rescue, transport of external sling loads between ships, low-level terrain flight, fuel-efficient loiter capability (ASW, AEW, or tanker), high speed airplane mode flight with or without external stores, and extended-duration missions with overload fuel. Recommendations are that design investigations of operational tilt-rotor V/STOL continue and that technology tasks involving experimental investigations with the XV-15 tilt-rotor research vehicle, laboratory test rigs, and models be undertaken. Limitations of the applicability of the results shown herein can be expected if nothing is done toward meeting the technology levels assumed for the designs. Graphs are presented as an aid for making trade-offs between tilt-rotor subsystem weights and performance parameters when alternatives exist among possible technology tasks. Such aids are useful to insure that limited resources be applied to the higher priority technology items. %B 38th Annual Conference, New York, New York, May 7-9 %I Society of Allied Weight Engineers, Inc. %C New York, New York %P 22 %8 5/7/79 %G eng %U https://www.sawe.org/papers/1273/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1273 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1273 %0 Conference Paper %B 38th Annual Conference, New York, New York, May 7-9 %D 1979 %T 1284. Advanced Materials and the Canadair Challenger %A Turner, Dr. , D R %A Hughes, T J %A Waterhouse, T A %K 10. Weight Engineering - Aircraft Design %X The weight control program on the CL-600 Challenger has been implemented by careful selection of materials to obtain a high specific strength. The airframe primary structure is constructed from advanced aluminum alloys whereas secondary structural components are made of light weight composite materials. In a continuing effort to reduce weight and at the same time take advantage of manufacturing cost saving, a program has been instituted to develop composite primary structure. This paper discusses the materials selected for the Challenger structure and cabin furnishings, and also addresses the development work on graphite/epoxy. %B 38th Annual Conference, New York, New York, May 7-9 %I Society of Allied Weight Engineers, Inc. %C New York, New York %P 10 %8 5/7/79 %G eng %U https://www.sawe.org/papers/1284/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1284 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1284 %0 Conference Paper %B 38th Annual Conference, New York, New York, May 7-9 %D 1979 %T 1296. Small Ship-Based VTOL Aircraft: A Design Exercise %A Flaig, J W %K 10. Weight Engineering - Aircraft Design %X A design exercise was performed to examine a number of moderate performance VTOL aircraft, other than the AV-8, which could be based aboard small ships in the mid-to-late 1980’s. Configurations were to have a takeoff gross weights about 20,000 lbs (9000 kg) with minimal external stores. The vehicles were designed to perform only vertical takeoffs and landings; no conventional or short takeoff and landing capability was required. The design mission consists of a simple high-altitude cruise and loiter profile; no combat or high-g maneuvering requirements were imposed. Current high-bypass-ration engines were studied as possible effective power plants for a pure VTOL aircraft. Unfortunately, the cruise efficiency of these engines was more than offset by the hover control problems inherent in the engineers due to gyroscopic effects. Designs using low bypass engines of the appropriate size were also examined. Although some attractive layouts were obtained, these required the use of lift engines which will not likely be available during the desired time period without a substantial immediate funding commitment. For a number of reasons, including performance level, availability, and cost, uprated versions of the Rolls Royce Pegasus-11 engine gave the most reasonable solutions. Of course, a funding commitment would also be required to make uprated version available. Efforts were taken to exploit the vertical-only takeoff/laning and the low g requirements to assure that the resultant configuration was simpy a styling change for the Hawker Siddely AV-8A. The basing of aircraft aboard small ships also presents haul ddown and securing problems, but solution to these appear to be written the state-of-the-art although they will require some engineering effort. A lightly-arm reconnaissance vehicle in the 20,000 lb (9,000 kg) class having a radius of approximately 300 mi (555 km) appears feasible, provide that the mission requirements remain simple; any multmission or high performance requirements would immediately result in increased size and weight. %B 38th Annual Conference, New York, New York, May 7-9 %I Society of Allied Weight Engineers, Inc. %C New York, New York %P 23 %8 5/7/79 %G eng %U https://www.sawe.org/papers/1296/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1296 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1296 %0 Conference Paper %B 38th Annual Conference, New York, New York, May 7-9 %D 1979 %T 1300. Advanced Technology Effects on V/STOL Propulsion System Weight %A R S St. John %K 10. Weight Engineering - Aircraft Design %X Optimization of a V/STOL propulsive concept requires a team effort involving the engine manufacturer, the air framer and of course the procuring agency. The optimization process can be significantly enhanced by establishing detail weight data for the entire propulsive system in the initial design phase. These detail weight data can serve as a basis for identifying: • Duplication in estimates and/or missing components, • Advanced technology weight payoff, • R&D funding allocations and scheduling profiles as a function of weight payoff, and • Design and integration responsibilities. The primary purposes of this paper are: • To provide a detailed weight accounting of all elements associated with the propulsive system. • Identify advanced technology effects on each of these elements. • Increase knowledge f weight problems associated with engine/airframer propulsive system integration. Vought's Tandem Fan configuration is used as the baseline for the development of the data presented in this paper. The weight estimation methodology employed are based on Vought's adaptation of the Reference(1) technique, Navy/Vought weight estimation methodology developed in References(2) and (3), and methodology developed under IR&D funding associated with Navy Type A and Type B V/STOL programs. %B 38th Annual Conference, New York, New York, May 7-9 %I Society of Allied Weight Engineers, Inc. %C New York, New York %P 23 %8 5/7/79 %G eng %U https://www.sawe.org/papers/1300/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1300 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1300 %0 Conference Paper %B 38th Annual Conference, New York, New York, May 7-9 %D 1979 %T 1314. Problems Associated With Cargo Airplanes Having Aft Mounted Engines %A Stephens, R E %K 10. Weight Engineering - Aircraft Design %X In preliminary design, the weight engineer is expected to perform weight and balance analysis on a wide variety of airplane configurations. One such configuration, which appears fairly frequently, is an aircraft with engines mounted on the aft fuselage instead of the wing. There may be a good, logical reason for an arrangement like this, but sometimes it is nothing more than a whim of the designer or an attempt to apply some innovation. In most cases this choice of engine location will cause penalties to the airplane, both in fuel and structural weight. In general, both the wing and fuselage weight is increased for fuselage mounted engines. Such a configuration also requires an extremely wide center of gravity envelope to allow for uniform payload loading. Although these problems exist to some extent on passenger aircraft, they become especially significant on cargo configurations. This paper examines the effects of engine location. A baseline configuration with four wing mounted engines is presented for comparison with several arrangements. In the first section of the analysis some simplifying assumptions are made which allow for some trends to be established. Three airplanes with engines mounted on the aft fuselage are examined, each with a different approach to the solution to the balance problems. In the second section of the study two of the configurations are analyzed in more detail. A third configuration, with two wing mounted engines and one tail mounted engine is added at this point for comparison purposes. The results indicate that if an airplane is designed for use as a cargo aircraft, it should have wing mounted engines. %B 38th Annual Conference, New York, New York, May 7-9 %I Society of Allied Weight Engineers, Inc. %C New York, New York %P 36 %8 5/7/79 %G eng %U https://www.sawe.org/papers/1314/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1314 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1314 %0 Conference Paper %B 38th Annual Conference, New York, New York, May 7-9 %D 1979 %T 1326. Weight Impact of VTOL %A Kalemaris, S %A York, P %K 10. Weight Engineering - Aircraft Design %X This paper studies the weight increments associated with vertical takeoff and landing capability as compared to conventional (horizontal) takeoff and landing (CTOL). Weight increments for various physical and ground rule requirements that transform a CTOL aircraft into a VTOL aircraft are evaluated. In order to fully understand the weight increments, preliminary designs of comparable CTOL aircraft are examined, along with Grumman'S VTOL designs. The "VTOL weight penalty" for shipboard operation is further defined by a study of the weight penalty for carrier basing a CTOL aircraft. The total effect of VTOL on subsonic aircraft, with low thrust required for CTOL, is presumably different from the effect on high performance supersonic aircraft with mission demands close to the VTOL requirement, and this difference is addressed. Finally, consideration is given to possible additional mission requirements for CTOL aircraft that stem from the difference in operational capability. %B 38th Annual Conference, New York, New York, May 7-9 %I Society of Allied Weight Engineers, Inc. %C New York, New York %P 18 %8 5/7/79 %G eng %U https://www.sawe.org/papers/1326/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1326 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1326 %0 Conference Paper %B 37th Annual Conference, Munich, West Germany, May 8-10 %D 1978 %T 1202. Sensitivity of Combat Aircraft Mass to Changes in Structural Design Safety Factors %A Platt, J T %A Wooller, R %K 10. Weight Engineering - Aircraft Design %X This paper makes a case for reviewing the level of flight safety factor. The evaluation of the flight safety factor and the area of influence on modern fighter structures are discussed. The potential savings achievable by reducing flight safety factor from the present level of 1.5 towards unity are evaluated for a range of strike fighter configurations, using both analytical and computer aided design techniques. Also examined is the influence of the potential savings of other design constraints, materials, aircraft configuration and mission. The particular causes examined demonstrate the trends and orders of savings. However, it is clear from the analysis that the savings can be significantly influenced by the above design parameters and that meaningful generalization cannot be made. It is apparent, however, that significant savings are possible if the design is sized around reduced flight safety factor at the project stage. The examples considered yield savings at combat in the order of 10% if the safety factor is reduced to 1.3, the maximum reduction possible using conventional aluminum alloys. Although limited experience of composites exists, the indications are that comparable or even greater mass savings should be possible. The current on-going technology research programs such as Active Control Technology (ACT) and advanced structural analysis, make that reduction in flight safety factor on the next generation of aircraft a real possibility. The proposal is made that flight safety factors should be progressively reviewed, starting with selected areas where there is a high level of confidence in the design and analysis techniques currently practiced. %B 37th Annual Conference, Munich, West Germany, May 8-10 %I Society of Allied Weight Engineers, Inc. %C Munich, West Germany %P 27 %8 5/9/78 %G eng %U https://www.sawe.org/papers/1202/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1202 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1202 %0 Conference Paper %B 37th Annual Conference, Munich, West Germany, May 8-10 %D 1978 %T 1207. Weight Optimization - A New Challenge of Weight Engineering %A Leitl, A K %K 10. Weight Engineering - Aircraft Design %X The Boeing Vertol Company, in striving for newer and better performing aircraft, has developed and implemented a new management system in support of aircraft weight optimization. This system is designed to be an engineering, management, and vendor control system to obtain maximum weight optimization performance in the design of an aircraft. An independent weight optimization group has been established within weight technology to control this function. Comparative tests have shown performance benefits of 10 to 20 percent improvements in empty weight compared to the old approach. It also showed that crash weight reduction programs, including associated problems, are no longer necessary. This new system was developed from experience gained on successful commercial and military aircraft weight control programs. Its effectiveness has received favorable comments from Boeing management, customers, and vendors alike. The long-range plan is to offer this system as part of future military contracts. This paper includes many useful hints for effective weight control. The approach, procedures, and techniques which are discussed can be tailored to any design program and can be adapted to any engineering department. Subjects discussed in the paper include the following highlights: • Why a new weight optimization approach was necessary (old approach, problems, and reasons for the problems • The objective defined and approach used to implement the new weight control system at Boeing Vertol • A description of the new weight optimization function • Examples of various weight optimization procedures, techniques, and requirements successfully adapted on past and current Boeing design programs • Example of a current design program which clearly demonstrates. the advantages of the new approach %B 37th Annual Conference, Munich, West Germany, May 8-10 %I Society of Allied Weight Engineers, Inc. %C Munich, West Germany %P 22 %8 5/9/78 %G eng %U https://www.sawe.org/papers/1207/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1207 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1207 %0 Conference Paper %B 37th Annual Conference, Munich, West Germany, May 8-10 %D 1978 %T 1212. Some Ideas for Layout and Design of Aircraft Using Liquid Hydrogen Fuel %A Lichte, M %K 10. Weight Engineering - Aircraft Design %X This paper was prepared in view of the coming fuel crisis and general energy shortage to get a first idea of what the use of liquid hydrogen for aircraft could mean. Other fuels as LH2 for fossils fuel replacement are possible; however, it was felt by the author that there is no other fuel working so ideally in a non-toxic “closed cycle" which is important for further life support on earth. A literature study showed no severe difficulties in using liquid hydrogen successfully as an aircraft fuel. Even flight tests have been carried out by NACA in 1956. There is a lot of information available for special features of tank and fuel system design, fuel cost estimations, and preliminary aircraft layouts including weight breakdowns. However, there was no estimation available of the economics of LH2-powered airliners flying in the subsonic speed range. Therefore, some estimations for such types of aircraft were carried out by rough hand methods, showing so drastically improved payload/take-off weight ratios that even at today’s US-hydrogen prices the LH2-aircraft would have no cost penalty in relation to an JP-fueled aircraft taking into account current fuel prices. Even more drastic improvements came out for VTOL-aircraft with LH2 fuel due to their more critical weight sensitivity, and the VTOL-range as a major disadvantage of VTOL-aircraft up to now could be increased very effectively. As a more general conclusion, the whole state of the art of optimum aircraft layout and design has to be reviewed if LH2 fuel for aircraft is considered. %B 37th Annual Conference, Munich, West Germany, May 8-10 %I Society of Allied Weight Engineers, Inc. %C Munich, West Germany %P 37 %8 5/9/78 %G eng %U https://www.sawe.org/papers/1212/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1212 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1212 %0 Conference Paper %B 37th Annual Conference, Munich, West Germany, May 8-10 %D 1978 %T 1214. Cost Efficiency Considerations Concerning the Application of Advanced Technologies for Civil Transport Aircraft %A Schneider, Dr. , W %A Wittmann, Dr. , M %K 10. Weight Engineering - Aircraft Design %X THE LIMITS AND POSSIBILITIES FOR THE USE OF ADVANCED TECHNOLOGIES TODAY This study was to give a survey of the spectrum of today’s' technological possibilities and an impression of the essential economical constraints of modern times. A considerable number of the technical innovations possible today will not be embodied in the first production series of the next generation of commercial aircraft on grounds of economy. Moreover, great technological efforts are necessary to ensure that the far stricter requirements can be met without a prejudicial effect on the operating costs. Fig. 9.1 shows the influences of the relevant cost parameters on the operating costs. It is evident that not only technical aspects are of significance. • The general inflation and the drastic effect of the limitation of the classical energy resources can, in the near future, partly be offset by the continuing growth in demand for: air transport. What remains to be done, can be summarized as follows: • Owing to the high development costs, the next generation of aircraft will have to stay in service until the year 2000 • Good timing of new programs will have a considerable influence on their success in the market • Aircraft families with a high degree of commonality between the individual variants are the most cost-effective solution for both operator and manufacturer • The adaptation of aircraft sizes to the actual demand is the most important economic factor • Fuel scarcity as well as more stringent environmental requirements and safety regulations make advanced technologies imperative. The following improvements fulfill the criterion of cost effectiveness: - application of high-by-pass engines of the 3rd generation - supercritical wing design (reduction of wing area, increase of thickness, shifting • "drag rise" limits) and, at the same time, improvement of the lift devices - digitalization of essential aircraft system components and introduction of new • equipment (automatic flight control systems, master warning, flight management • computers) - use of fiber components in the secondary structure (fairings, spoilers, lift • dumpers, interior) • In view of the increasing cargo volume, the "8 abreast" fuselage cross-section is considered the most cost-effective solution for capacities of 200 passengers and more • The necessary additional expenditure for development costs is only justified for new developments of larger capacities (> 160 passengers). In the case of derived aircraft, the minimum limit for profitability lies with aircraft capacities of 130 passengers • New development only reach a break-even point when more than 450 aircraft are' • built • The trend towards automation in production will continue to increase. %B 37th Annual Conference, Munich, West Germany, May 8-10 %I Society of Allied Weight Engineers, Inc. %C Munich, West Germany %P 113 %8 5/9/78 %G eng %U https://www.sawe.org/papers/1214/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1214 %1 Non-Member Price: $56.50; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 56.5 %4 SAWE1214 %0 Conference Paper %B 37th Annual Conference, Munich, West Germany, May 8-10 %D 1978 %T 1240. Development of the Shortened Airbus Derivative A300B10 and the Problem Achieving Optimum Weight %A Klug, Dr. , H G %A Kramer, S %K 10. Weight Engineering - Aircraft Design %X It is the intention of the European Industry to develop as complete a range of civil airliners as possible. The nucleus for this range of airliners to be developed will be the Airbus, and Airbus Industrie will be the central organization for all future programs. Extension of the Airbus A300 family is seen as highest priority. It is the intention to develop, from the firm basis of the successful B2/B4, a complete family of A300 variants having carefully chosen size and range relationships, offering to the airlines the attraction of a high degree of airframe, engine and systems commonality. %B 37th Annual Conference, Munich, West Germany, May 8-10 %I Society of Allied Weight Engineers, Inc. %C Munich, West Germany %P 23 %8 5/9/78 %G eng %U https://www.sawe.org/papers/1240/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1240 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1240 %0 Conference Paper %B 37th Annual Conference, Munich, West Germany, May 8-10 %D 1978 %T 1260. Subsonic V/STOL Concepts With Emphasis on Weight Effects %A Louthan, J D %A R S St. John %K 10. Weight Engineering - Aircraft Design %X This paper emphasizes weight effects associated with propulsion system cycle and design parameters, multi-mission commonality and advanced materials usage. Vought’s V-530 Tandem Fan concept is used as the comparison basis. Technology developments shown to be key to V/STOL Type A system development include: • Extensive application potential for advanced composite structural components throughout the airframe and in selected propulsion system components. • Lift/cruise fan technology for both thrust and vehicle control. • Avionics technology developments in Large Scale Integrated Circuitry, conformal antennas and information processing. %B 37th Annual Conference, Munich, West Germany, May 8-10 %I Society of Allied Weight Engineers, Inc. %C Munich, West Germany %P 13 %8 5/9/78 %G eng %U https://www.sawe.org/papers/1260/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1260 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1260 %0 Conference Paper %B 37th Annual Conference, Munich, West Germany, May 8-10 %D 1978 %T 1261. Ground Effects of V/STOL Vehicles %A WIENRAUB, RA %K 10. Weight Engineering - Aircraft Design %X The purpose of this paper is to introduce the problem of propulsion induced ground effects. These ground effects are usually associated with V/STOL aircraft which utilize medium or high disc loading propulsion devices (lift jets, fans, and augmenters) for vertical flight. The exhaust flow from these propulsion systems can affect the ground environment, the aircraft and the propulsion device itself. These interactions (ground effects) can have a severe impact on the vertical takeoff and landing performance of V/STOL aircraft. %B 37th Annual Conference, Munich, West Germany, May 8-10 %I Society of Allied Weight Engineers, Inc. %C Munich, West Germany %P 19 %8 5/9/78 %G eng %U https://www.sawe.org/papers/1261/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1261 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1261 %0 Conference Paper %B 37th Annual Conference, Munich, West Germany, May 8-10 %D 1978 %T 1262. Use of Radio Controlled Models in the Conceptual Development of V/STOL Vehicles %A Kress, R W %K 10. Weight Engineering - Aircraft Design %X Grumman has been utilizing radio controlled models for a number of years on many of its programs. The benefits of radio controlled models will be discussed, as well as the basic model equipment used at Grumman. Fluidic rate sensors and electrostatic autopilot will be discussed as well as the operation of both. %B 37th Annual Conference, Munich, West Germany, May 8-10 %I Society of Allied Weight Engineers, Inc. %C Munich, West Germany %P 25 %8 5/9/78 %G eng %U https://www.sawe.org/papers/1262/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1262 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1262 %0 Conference Paper %B 37th Annual Conference, Munich, West Germany, May 8-10 %D 1978 %T 1267. Influence of Carbon Technology on Weight and Cost of a Fighter Wing %A Seibert, P E %A Arendts, F J %K 10. Weight Engineering - Aircraft Design %X A study was performed aiming to evaluate the best structural concept for a composite fighter wing to achieve maximum weight savings and keep the costs as they are for a metal wing. It was decided, by reasons of costs,to use only carbon-composite and no boron-composite although boron has some advantage in the upper compression wing panel. Another restriction was to use a technology that is almost available to have the option to test and fly the wing in the early 80’s. The work was done in two phases. During phase I, a preliminary phase, a lot of different structural wing box concepts and particularly wing fuselage attachment concepts have been schemed and analysed. At the end of phase I four concepts have been selected for a deeper investigation. In phase II, these four concepts have been designed, stressed and weighted. For the two most promising concepts, costs have been evaluated. This paper presents the results of that study. %B 37th Annual Conference, Munich, West Germany, May 8-10 %I Society of Allied Weight Engineers, Inc. %C Munich, West Germany %P 24 %8 5/9/78 %G eng %U https://www.sawe.org/papers/1267/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1267 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1267 %0 Conference Paper %B 37th Annual Conference, Munich, West Germany, May 8-10 %D 1978 %T 1268. Practical Considerations in Composite Designs %A McBee, O B %K 10. Weight Engineering - Aircraft Design %X Practical considerations in advanced composite designs based on MCAIR experience are provided. Some of the advantages of composites to offset new emphasis on “design drivers” that tend to increase weight are noted. Production type composite applications on MCAIR aircraft are illustrated along with a weight comparison. Some of the considerations for using or not using composites in actual production parts are described. It is predicted that advanced designs such as V/STOL will sorely need a “large dose” of composites, but they must be judiciously selected and designed. %B 37th Annual Conference, Munich, West Germany, May 8-10 %I Society of Allied Weight Engineers, Inc. %C Munich, West Germany %P 7 %8 5/9/78 %G eng %U https://www.sawe.org/papers/1268/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1268 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1268 %0 Conference Paper %B 36th Annual Conference, San Diego, California, May 9-12 %D 1977 %T 1154. Why Fly Supersonically? %A Mijares, R D %A Salvaggio, J C %K 10. Weight Engineering - Aircraft Design %X Some of the significant differences between contemporary subsonic and supersonic commercial aircraft are highlighted. Technical problems, unique to high speed flight, are presented, along with their effect on the mass fraction and center of gravity control. The potential speed benefit is contrasted against the environmental acceptability and economic viability of a commercial supersonic cruise aircraft. The far-term improvement in mass fractions, due to technology advancements in materials, active controls and propulsion, are projected, with their resulting impact on the aircraft. %B 36th Annual Conference, San Diego, California, May 9-12 %I Society of Allied Weight Engineers, Inc. %C San Diego, California %P 7 %8 5/9/77 %G eng %U https://www.sawe.org/papers/1154/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1154 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1154 %0 Conference Paper %B 36th Annual Conference, San Diego, California, May 9-12 %D 1977 %T 1163. Application of the Thrust Augmentation Wing Principle for Potential Military Use %A Petrushka, E M %A Winnett, A G %K 10. Weight Engineering - Aircraft Design %X The development of heavier-than-air powered flight encompassed over 70 years and literally thousands of different fling designs. The evolutionary process underlying this development, while considerable, has retained a general state of separation between achievement of aerodynamic lift and propulsive force required for forward flight. The preoccupation of the Wright Brothers and their contemporaries was the addition of motive thrust to what were otherwise “gliders”. The modern airliner and high performance fighter are no different from the earliest aircraft in this regard, the consequence of which has been the need for long take-off and Landing runs. (Figure 1). The notable exception is the helicopter which achieves efficient vertical flight but accepts as position on the scale of tradeoffs towards the low speed end of the flight regime. This general situation has always been well known. With the advent of turbine engines whose power-to-weight ratios were improved over those of reciprocating engines, aircraft designers perceived the possibility that high performance aircraft could achieve vertical flight through power lift. The history of the last 25 years shows that this was easier said than done as attested by reaching operational service is the Hawker Siddley the multitude of configurations built and tested “Harrier,” although thjs required a considerable (Figure 2). The only aircraft of this vast family development time period. Tremendous resources have gone into these programs to achieve vertical flight and also into the minimizing of take-off and landing speeds of conventional aircraft through high lift technology. The desire to merge these two objectives has led to the concept of the “Thrust Augmented Wing.” The TAW is an approach to integrating lift, propulsion, and control so that an otherwise normal airfoil can be “flying” not only at high aerodynamic speeds, but also at zero speed, and any speed in between with smooth conversions in acceleration and deceleration. The general arrangement of TAW with the main elements is shown in Figure 3. Current configurations have three movable flaps, one upper “center ejector” and two lower “diffusers.” Engine exhaust air can either be directed aft in a normal manner or completely diverted into these flaps and ejected through long slot nozzles, directly for the center ejector and over coanda surfaces for the diffusers. All subsequent control of the TAW’S thrust vector is performed by proper movement of these three surfaces. %B 36th Annual Conference, San Diego, California, May 9-12 %I Society of Allied Weight Engineers, Inc. %C San Diego, California %P 16 %8 5/9/77 %G eng %U https://www.sawe.org/papers/1163/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1163 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1163 %0 Conference Paper %B 36th Annual Conference, San Diego, California, May 9-12 %D 1977 %T 1176. The Aerodynamic Vane Control Aircraft for V/STOL %A Raha, J E %K 10. Weight Engineering - Aircraft Design %X This paper is a description of Grumman’s two-engine, two-fan V/STOL Design 698 for ASW/AEW missions. After a brief discussion of the Nutcracker, a predecessor design, the paper presents a description of the unique configuration features of Design 698 rather than attempting to summarize the entire V/STOL program. Concepts discussed include the V/STOL nacelle, composites applications, engine sizing philosophy and the conformal radar, Weight statements and summaries of VTOL weight increments are included, %B 36th Annual Conference, San Diego, California, May 9-12 %I Society of Allied Weight Engineers, Inc. %C San Diego, California %P 24 %8 5/9/77 %G eng %U https://www.sawe.org/papers/1176/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1176 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1176 %0 Conference Paper %B 36th Annual Conference, San Diego, California, May 9-12 %D 1977 %T 1177. Advanced Technology Emphasis for a 1985 Tactical Supersonic Cruise Airplane %A Ciminera, V R %A Giesler, W %A Schwartz, P M %K 10. Weight Engineering - Aircraft Design %X Cost, performance and survivability imperatives will require quantum jumps in next generation weapon systems advance technology applications. Emerging technologies in aerodynamics, materials, and propulsion systems will significantly reduce takeoff gross weight and life cycle cost and improve cost effectiveness. Optimum cost/benefit relationships will determine where the emphasis on technology application is placed. This paper examines how the order of technology applications will impact the total weapon system payoff. %B 36th Annual Conference, San Diego, California, May 9-12 %I Society of Allied Weight Engineers, Inc. %C San Diego, California %P 18 %8 5/9/77 %G eng %U https://www.sawe.org/papers/1177/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1177 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1177 %0 Conference Paper %B 35th Annual Conference, Philadelphia, Pennsylvania, May 24-26 %D 1976 %T 1104. Weight and Balance Considerations in the Design of the A-10A Close Air Support Aircraft %A Leavy, G C %K 10. Weight Engineering - Aircraft Design %X This paper describes the design features included in the A-10A Close Air Support Aircraft which had a significant effect on the aircraft weight and balance. Particular attention is given to the survivability features and the 30 MM gun installation, which ae peculiar to the A-10 and had the greatest effect on the weight an balance. Included are quantitative assessments of the first order weight increments due to the design features as well as discussions of the effect of these design features on the configuration and size of the aircraft. %B 35th Annual Conference, Philadelphia, Pennsylvania, May 24-26 %I Society of Allied Weight Engineers, Inc. %C Philadelphia, Pennsylvania %P 24 %8 5/24/76 %G eng %U https://www.sawe.org/papers/1104/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1104 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1104 %0 Conference Paper %B 35th Annual Conference, Philadelphia, Pennsylvania, May 24-26 %D 1976 %T 1127. The Next Generation Subsonic Transport %A Marsh, D P %K 10. Weight Engineering - Aircraft Design %X This paper discusses the current design approach at McDonnell Douglas toward satisfying the market requirements and operating economics for a next-generation commercial subsonic transport. First, the near-term design objects are discussed. The most significant change in these objectives since design of the current generation of commercial transports is the increased emphasis on reduced fuel consumption. Second, the development of a configuration to satisfy these objectives is reviewed. Specific design trades addressed include wing geometry studies, advanced technology applications, and fuselage and engine configuration studies. Finally, the performance and design characteristics of a current study baseline aircraft are reviewed. Study results and conclusions to date indicate that he next-generation transport will probably have the following features: 1. All-new wing design with higher aspect ratios for reduced drag 2. Advance high-lift system for reduced noise and wing area 3. Incorporation of advanced technologies like supercritical wing, composite materials and relaxed static stability to reduce weight and fuel burned 4. Reduced passenger capacity over current wide-body transports to meet market requirements 5. Reduce cruise speed for minimum operating cost 6. Commonality with existing transport aircraft to reduce development costs. %B 35th Annual Conference, Philadelphia, Pennsylvania, May 24-26 %I Society of Allied Weight Engineers, Inc. %C Philadelphia, Pennsylvania %P 9 %8 5/24/76 %G eng %U https://www.sawe.org/papers/1127/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1127 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1127 %0 Conference Paper %B 34th Annual Conference, Seattle, Washington, May 5-7 %D 1975 %T 1042. Payoffs From Active Controls Technology Applications - Transport Aircraft %A Marsh, D P %K 10. Weight Engineering - Aircraft Design %X A comprehensive mass properties analyses process is essential in determining reliable payoffs for reduced static stability (RSS) and load alleviation and mode suppression (LAMS). This process is discussed as it applies to advance design studies relating to the application of active controls to transport aircraft. Reference is made to the Douglas mass properties estimation system (MAPES) which is a computer program for transport aircraft weight estimation, and is very adaptable to active controls applications. Weight effects to structural components resulting from the application of RSS and LAMS are discussed, as are systems implications. Payoffs are discussed in terms of vehicle range, vehicle size, and increased payload. %B 34th Annual Conference, Seattle, Washington, May 5-7 %I Society of Allied Weight Engineers, Inc. %C Seattle, Washington %P 13 %8 5/5/75 %G eng %U https://www.sawe.org/papers/1042/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1042 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1042 %0 Conference Paper %B 34th Annual Conference, Seattle, Washington, May 5-7 %D 1975 %T 1055. Rotorcraft Technology 1985 - 1990 %A Lilley, E G %K 10. Weight Engineering - Aircraft Design %X This paper is the result of literature surveys, personal research and assessment of the direction to which technology is advancing towards the year 1990. It represents an overall projection of Structures, Sub-systems and Equipment, highlighting those specific areas where major advances in the state-of-the-art are anticipated and how those advances will effect the role of the Weight Engineer. Projection Philosophy is briefly discussed from the standpoint of (i) Evolution - which are logical extrapolations from the known base and (ii) Revolution - which are identified as special events or discontinuities from the logical progression of known technology. The ideal forecasting methodology is the mixing of both subjective and objective thought processes together with an analytical technique--this is much more reliable because an opportunity is given to input those changes which fall into the category of intuitive rather than purely analytical. Before we attempt to project the future, we must be sure we understand the present. Technological innovations result from changing motivations. This paper discusses briefly the technology achievements to date, then examines the possible sociotechnoeconomic environment of the time period discussed, with its obvious influence on aerospace and in particular the rotary wing field. %B 34th Annual Conference, Seattle, Washington, May 5-7 %I Society of Allied Weight Engineers, Inc. %C Seattle, Washington %P 23 %8 5/5/75 %G eng %U https://www.sawe.org/papers/1055/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1055 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1055 %0 Conference Paper %B 34th Annual Conference, Seattle, Washington, May 5-7 %D 1975 %T 1056. The Challenge of Weight and Balance Control and Design-To-Cost for Y/C-14 Prototype Development %A Hutton, J G %K 10. Weight Engineering - Aircraft Design %X The YC-14 is being developed by Boeing for the United States Air Force in a program intended to improve transport airlift capability. Program goals include STQL performance and a significant expansion of tactical payload carrying ability within cost constraints. In response, the Boeing YC-14 development objectives include the following: * Demonstrate upper surface blowing (WSB) as an efficient STQL propulsive lift augmentation system * Demonstrate YC-14 utility in expanding tactical airlift capability * Demonstrate YC-14 ability to accommodate unusual (large, heavy) payloads * Prove the ability to meet cost goals The weight and balance control objective on the YC-14 program is to help direct the prototype development in meeting the program goals. YC-14 prototype design involves significant challenges. Both time and funding are limited for testing to provide problem solutions. Time is also limited for design layout cycling to achieve best design. Early in design stages the design-to-cost goals required direct involvement at a highly detailed level with few people. YC-14 weight and balance control activities have recognized and successfully dealt with those challenges. The design work package team concept, utilized on the YC-14 program, is instrumental in providing fast, accurate, and widely disseminated information early in the design phase. A high degree of weight staff-initiated direction is providing a sound basis for the program decision-making process. %B 34th Annual Conference, Seattle, Washington, May 5-7 %I Society of Allied Weight Engineers, Inc. %C Seattle, Washington %P 16 %8 5/5/75 %G eng %U https://www.sawe.org/papers/1056/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1056 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1056 %0 Conference Paper %B 34th Annual Conference, Seattle, Washington, May 5-7 %D 1975 %T 1065. Liquid Hydrogen - Fuel of the Future? %A Jenson, R %K 10. Weight Engineering - Aircraft Design %X The domestic and world supplies of petroleum are not unlimited. It is forecast that before the end of the 20th century, world oil production will reach a peak and begin a steady decline. A survey of possible substitute fuels reveals that liquid hydrogen may be the leading contender to replace petroleum. Already, its potential price per BTU is competitive with JP fuel. Its greater heat of combustion and its negligible impact on air pollution are also very worthwhile attributes. Liquid hydrogen is compared to petroleum-based fuels for propulsion of various types of vehicles. For supersonic aircraft, a lighter, less costly design can be achieved through the use of this cryogenic fuel. Takeoff weight can be reduced by more than 40%, operational empty weight and cost by more than 20%. For subsonic, medium-range aircraft, takeoff and operational weights can be reduced by 20%and l0%, respectively. A brief review of the methods used to produce this fuel of the future ads to an outline of the ways in which our needs may be met. For the near term, LH2 can be manufactured from coal or lignite. In the not-too-distant future, nuclear power of solar collectors cm generate large quantities of hydrogen by electrolysis or by thermochemical splitting of water. A comparison of relative hazards shows that LH2 is actually safer to use than petroleum fuels. The rapidly growing air-transportation industry has the most to gain by leading the way into the hydrogen economy and severing its dependence on a disappearing energy source. After aviation leads the way, hydrogen will readily enter wider industrial and domestic use, making the world a cleaner and therefore a healthier place to live. %B 34th Annual Conference, Seattle, Washington, May 5-7 %I Society of Allied Weight Engineers, Inc. %C Seattle, Washington %P 43 %8 5/5/75 %G eng %U https://www.sawe.org/papers/1065/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1065 %1 Non-Member Price: $21.50; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 21.5 %4 SAWE1065 %0 Conference Paper %B 34th Annual Conference, Seattle, Washington, May 5-7 %D 1975 %T 1091. Weight Contribution to Fuel Conservation for Terminal Area Compatible Aircraft %A Hanks, G W %K 10. Weight Engineering - Aircraft Design %X The potential weight characteristics of advanced aircraft are reviewed for their possible contribution to reduction of fuel use by future transports. The trades between weight reduction versus increased aerodynamic and operating efficiency are described. Weight reduction through use of advanced technology in items such as structure and airfoils, proper choice of engines, and revised environmental control systems is shown to offer a direct contribution to fuel conservation. Wing plan form optimization results in increased weight with thin, high aspect ratio and reduced sweep wings; however, weight penalties are beneficially countered by a pronounced increase in aerodynamic efficiency. Results of isolated studies of several technical areas applied to an example 200 passenger, 5556 km (3000 nmi) design range transport operated at a long-range cruise Mach number of 0.80 are discussed. Overall, 21.6% reductions in operational empty weight and takeoff gross weight are obtained, as compared to a conventional design that utilizes current technology. The weight penalties incurred by design features to reduce congestion, noise, and emissions in the terminal area are discussed. It is shown that features for reduction of congestion (delay) and emissions also offer fuel reduction potential; however, weight and fuel-use penalties result from noise reduction features. The considerable research and technology effort required to achieve a resulting nominal 25% fuel reduction potential on future aircraft during the latter half of the 1980 decade is outlined. %B 34th Annual Conference, Seattle, Washington, May 5-7 %I Society of Allied Weight Engineers, Inc. %C Seattle, Washington %P 25 %8 5/5/75 %G eng %U https://www.sawe.org/papers/1091/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 1091 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE1091 %0 Conference Paper %B 32nd Annual Conference, London, England, June 25-27 %D 1973 %T 969. Cost-Weight Interface in Aircraft Design %A Kenyon, R E %A Mueller, R N %K 10. Weight Engineering - Aircraft Design %X This paper presents the results of a study sponsored by the U.S. Air Force Flight Dynamics Laboratory aimed at developing preliminary design level techniques to estimate the cost of flight vehicle basic structure, identifying sensitivity to the structural concepts and materials used. The study is intended to provide improved and more systematic cost estimating techniques in support of cost as a design parameter for military aircraft. Such usage is currently being recognized as a major design consideration. The term design-to-cost has been used to describe this objective, although the term has been given a number of different interpretations. Two estimating techniques have resulted. One is concerned with supporting trade studies and predicts the relative cost of airframe structures that use different types of materials and constructions. The second estimates aircraft subsystem costs and adds these to the results of the first technique, providing total airframe system cost in terms of man-hours and materials, while retaining sensitivity to types of material and construction. The trade study estimating technique involves using the output of automated structural design synthesis programs as cost—related variables and derived cost estimating factors as dummy variables in estimating relationships covering detailed basic structure elements (e.g., ribs, spars, skin panels, etc.). Weight is the primary synthesis program output used. The cost-weight interface is modified by cost estimating factors derived from an analysis of the relative complexity of the manufacturing process associated with typical types of construction and material. Relative complexity is referenced to benchmark cases based on historical cost data. The horizontal stabilizer was used as a demonstration case. The method is currently being extended to the entire basic structure. Wing and fuselage cost data are being collected, structural synthesis programs are being suitably modified, cost estimating relationships are being formulated, and a full range of complexity factors are being derived. The second technique, system costing, uses weight and subsystem characteristics as the primary cost-related variables. It produces estimates structured so as to be comparable to traditional estimating and is modularized for compatibility with integrated design procedures. These estimating techniques are particularly useful for preliminary design phase cost estimating in support of design trade studies involving choices in structural concepts where vehicle and structural synthesis programs are available. They also appear to be particularly suited to integrated computer-aided design procedures. The primary application to be made by AFFDLI will be in advanced development programs, in structural research and development independent of systems acquisition, in assessments of the impact of various technologies, and in providing an alternative source of estimates against which weapons systems proposals can be evaluated. %B 32nd Annual Conference, London, England, June 25-27 %I Society of Allied Weight Engineers, Inc. %C London, England %P 24 %8 6/24/73 %G eng %U https://www.sawe.org/papers/0969/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 0969 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE0969 %0 Conference Paper %B 31st Annual Conference, Atlanta, Georgia, May 22-25 %D 1972 %T 907. A Summary of the Design Synthesis Process %A Ladner, F K %A Roch, A J %K 10. Weight Engineering - Aircraft Design %X This report provides an overview of computerized aircraft synthesis through a summary of Vought Aeronautics Company's Aircraft Synthesis Analysis Program, ASAP. This program is an aircraft synthesis computer model designed to size and optimize aircraft during design of potential aircraft systems. ASAP combines into one computer program analysis techniques and work procedures of the design process; automates a significant portion of the design process (i.e., initiation, analysis and optimization); and is applicable to all stages of the advanced design acquisition cycle. The ASAP development plan is presented with emphasis placed on ASAP'S evolutionary and practical development approach and its modular construction. Development status is reviewed and reveals that the analysis phase of the design process has been automated and feasibility of automating the initiation and optimization phases has been established. The existing ASAP computer program is described. Operational experience is reviewed in terms of program execution time, utilization, and cost and time savings. %B 31st Annual Conference, Atlanta, Georgia, May 22-25 %I Society of Allied Weight Engineers, Inc. %C Atlanta, Georgia %P 40 %8 5/22/72 %G eng %U https://www.sawe.org/papers/0907/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 0907 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE0907 %0 Conference Paper %B 31st Annual Conference, Atlanta, Georgia, May 22-25 %D 1972 %T 908. An Aerodynamic Model Applicable to the Synthesis of Conventional Fixed Wing Aircraft %A Peyton, R S %K 10. Weight Engineering - Aircraft Design %X In the preliminary design stage of modern day aircraft the ability to determine the tradeoffs in large matrix of design or system variables, from the standpoint of mission , gross weight , or cost effectiveness , is mandatory. An effective tool used at the Lockheed-California Company to affect such tradeoffs is the ASSET (Advanced Systems Synthesis and Evaluation Technique) computer program. This ASSET computer program is comprised of many computer models or subroutines such as configuration generation, weights, aerodynamics, propulsion, and cost. Following input of the desired configuration variables, these subroutines combine together to perform and cost the matrix of desired aircraft. The aerodynamics model of ASSET defines the component lift and drag of each configuration variable and sums these components into the total flaps up airplane lift and drag. The sources of drag considered by the model include friction, profile, compressibility, wave induced protuberance and drag of external stores. The model uses configuration data defining aircraft component size and shape and prediction techniques to generate the matrix of parametric aerodynamic data as, a function of Mach number, altitude and lift coefficient. The steps required to produce the parametric drag data include: (1) generating component friction drag buildups for a Mach number-altitude matrix; (2) determining the zero - lift transonic drag rise and supersonic wave drag for the wing; (3) generating component zero - lift pressure drag buildups for a range of Mach numbers; (4) determining the parabolic induced drag factor over the speed regime; (5) computing induced drag increments due to drag divergence for a matrix of lift coefficients and transonic Mach numbers. Experience gained through design application demonstrates that the model is flexible enough to accommodate a wide variety of fixed-wing aircraft configurations. The drag data provided by the model are applicable in the subsonic through supersonic flight regime for the moderate lift coefficients usually encountered over the mission profile and the accuracy is consistent with the requirements of the conceptual design phase. %B 31st Annual Conference, Atlanta, Georgia, May 22-25 %I Society of Allied Weight Engineers, Inc. %C Atlanta, Georgia %P 15 %8 5/22/72 %G eng %U https://www.sawe.org/papers/0908/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 0908 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE0908 %0 Conference Paper %B 31st Annual Conference, Atlanta, Georgia, May 22-25 %D 1972 %T 909. Performance Methods for Aircraft Synthesis %A Moran, W J %K 10. Weight Engineering - Aircraft Design %X The aircraft configuration synthesis process is described from the viewpoint of the performance engineer as a contribution to an interdisciplinary examination of the process. In addition , the performance engineer's task in the synthesis loop is described, as well as two computer programs being developed at the Fort Worth operation of Convair Aerospace. The first of these programs, MAPP (Mission Analysis and Performance Program), contains methods for computation of most types of performance data. The second, IMP (Interim Mission Program), is a general mission integration procedure. IMP is intended for eventual merger with MAPP to form the performance module of an integrated configuration synthesis system for conventional aircraft. The interfaces needed by the proposed performance module with other modules in the system are summarized. %B 31st Annual Conference, Atlanta, Georgia, May 22-25 %I Society of Allied Weight Engineers, Inc. %C Atlanta, Georgia %P 45 %8 5/22/72 %G eng %U https://www.sawe.org/papers/0909/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 0909 %1 Non-Member Price: $22.50; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 22.5 %4 SAWE0909 %0 Conference Paper %B 31st Annual Conference, Atlanta, Georgia, May 22-25 %D 1972 %T 910. Engine and Airplane - Will It Be a Happy Marriage? %A McIntire, W L %A Beam, P E %K 10. Weight Engineering - Aircraft Design %X In the past, new aircraft designs have generally been restricted to the use of "off-the-shelf" engines. As a rule, engine selection has been limited to two or three power-plants which are either in production or under development. Thus, the range of engine characteristics has been extremely narrow. In this study, all such restrictions have been removed, and the engine aerodynamic cycle, size, and configuration are dictated solely by the aircraft mission requirements. A matrix of engines was designed at various bypass ratios, pressure ratios, and turbine temperatures. The effect of these variables on engine performance and weight-and, thus, on the aircraft mission performance-is examined. Particular emphasis is given to the methods used to obtain the weight of each of the engines. The methods illustrated can be adapted to permit selection of the optimum engine for any aircraft mission. %B 31st Annual Conference, Atlanta, Georgia, May 22-25 %I Society of Allied Weight Engineers, Inc. %C Atlanta, Georgia %P 13 %8 5/22/72 %G eng %U https://www.sawe.org/papers/0910/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 0910 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE0910 %0 Conference Paper %B 31st Annual Conference, Atlanta, Georgia, May 22-25 %D 1972 %T 911. Configuration Analysis as Applied to Aerospace Vehicle Design Synthesis %A Ridenour, R W %K 10. Weight Engineering - Aircraft Design %X One of the tasks encountered in aerospace vehicle design synthesis is the analysis of the actual geometric configuration. The proper relationships between body, wing, and tail sizes are necessary to maintain aerodynamic performance requirements. These geometric data are, in general, interactive one upon the others. McDonnell Douglas Corporation has investigated various methods by which these data can be analyzed to establish the required vehicle geometric configuration. Very specific uses have been found for each method examined often with only subtle differences between the results produced by different methods. From the experience gained in various sizing programs, several conclusions have been reached. There are multiple approaches to the geometry definition and sizing. Any weight-sizing must tailor the geometry to interface with the aero-design requirements. The time available to produce the computer program and the computer capacity many times demand that simplified geometries be adequate. %B 31st Annual Conference, Atlanta, Georgia, May 22-25 %I Society of Allied Weight Engineers, Inc. %C Atlanta, Georgia %P 35 %8 5/22/72 %G eng %U https://www.sawe.org/papers/0911/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 0911 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE0911 %0 Conference Paper %B 31st Annual Conference, Atlanta, Georgia, May 22-25 %D 1972 %T 912. The Weight Module - A Keystone in the Aircraft Synthesis Program %A Crossen, R L %K 10. Weight Engineering - Aircraft Design %X The weight module of the aircraft synthesis program must meet the requirement of integrating all of the design parameters into the single parameter, weight or mass of the real vehicle. This requirement forces the weight module to include consideration of aircraft design disciplines which are not separate modules of the total synthesis program. The weight module consists of a series of complex relationships which must consider all facets of the vehicle design. The generalized component weight equation presented is useful for building the computational element of the module, while retaining total flexibility to tailor the module to each specific design problem. The generalized computational routine makes the engineer an integral part of the synthesis process by requiring him to define the weight equations fours e in any specific application. Elimination of the need to continually develop new computational routines allows more time to be spent in the area of methods development. The development of improved weight estimation methods is important to the creation of good weight modules for synthesis programs. %B 31st Annual Conference, Atlanta, Georgia, May 22-25 %I Society of Allied Weight Engineers, Inc. %C Atlanta, Georgia %P 12 %8 5/22/72 %G eng %U https://www.sawe.org/papers/0912/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 0912 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE0912 %0 Conference Paper %B 30th Annual Conference, Newport Beach, California, May 3-5 %D 1971 %T 894. V/STOL Airplanes With Vectored Thrust Propulsion Systems %A Graham, T J %K 10. Weight Engineering - Aircraft Design %X This paper is based on the Harrier airplane designed and produced be Hawker Siddeley Aviation Ltd. and which uses the Rolls Royce Pegasus engine. Some basic V/STOL propulsion systems are compared with the vectored thrust concept to establish a basis for selecting vectored thrust. Special design considerations of V/STOL airplanes, with respect to weight and balance, typified by the vectored thrust design are examined. V/STOL airplanes have their own special design considerations because of their high sensitivity with respect to performance of weight and center of gravity – lift – thrust relationship. This paper considers the competitive stature of the vectored thrust V/STOL with a conventional takeoff and landing aircraft with short field capability, on a common basis i.e., when designed to a common set of ground rules. V/STOL vectored thrust airplanes are competitive in the Close Air Support role. The lower the takeoff and landing distance becomes, the greater is their competiveness. %B 30th Annual Conference, Newport Beach, California, May 3-5 %I Society of Allied Weight Engineers, Inc. %C Newport Beach, California %P 15 %8 5/3/71 %G eng %U https://www.sawe.org/papers/0894/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 0894 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE0894 %0 Conference Paper %B 30th Annual Conference, Newport Beach, California, May 3-5 %D 1971 %T 899. The Administration of a Cost/Weight Tradeoff Program %A Schmiedeke, G W %K 10. Weight Engineering - Aircraft Design %X This paper presents the administrative techniques of a cost/weight tradeoff program for a modern jet transport airplane. It introduce the concept and philosophy of using a defined cost/weight value as part of basic design criteria and discusses the full scope of a program to assure its overall application to vehicle design. The role of Management and Weight Engineering in Weight Reductions Programs is discussed in detail. Particular emphasis is placed on the concept of generating and maintaining a large number of weight saving ideas from which Management can select the type and amount of weight reduction that appears desirable for meeting weight guarantees and the competition. Procedures for converting weight saving ideas into actual hardware weight reductions are presented in outline form. Problems associated with assuring weight optimization of subcontract and vendor products are also discussed in detail. %B 30th Annual Conference, Newport Beach, California, May 3-5 %I Society of Allied Weight Engineers, Inc. %C Newport Beach, California %P 19 %8 5/3/71 %G eng %U https://www.sawe.org/papers/0899/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 0899 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE0899 %0 Conference Paper %B 29th Annual Conference, Washington, D. C., May 4-6 %D 1970 %T 838. A Definition of the Aircraft Stretch Efficiency Factor %A Rugg, H R %K 10. Weight Engineering - Aircraft Design %X This paper presents a method of defining the aircraft stretch efficiency factor as a function of productivity and as a function of the aircraft's payload growth factor. The stretch efficiency factor, an effective means of evaluating the ability of a candidate aircraft to meet an arbitrary target mission, can also be used to evaluate potential methods of stretch and to estimate the amount of stretch required by each method. This paper also provides a means of estimating the payload capability and required take-off gross weight of candidate aircraft for the target mission requirements. The efficiencies presented in this paper are determined by using aircraft growth factors and the interrelationship of mission parameters. Since the method is independent of the target mission, growth factors and mission parameter sensitivities of a candidate stretch aircraft need only be determined once. In this study the optimal target and candidate stretch aircraft are determined by maximizing specific productivity. The study utilizes a computer trending model which displays outputs on a cathode ray tube (CRT). The interactive capabilities of the CRT terminal render it highly suitable for this method. Typical stretch efficiencies are presented for a transport helicopter. %B 29th Annual Conference, Washington, D. C., May 4-6 %I Society of Allied Weight Engineers, Inc. %C Washington, DC %P 38 %8 5/4/70 %G eng %U https://www.sawe.org/papers/0838/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 0838 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE0838 %0 Conference Paper %B 29th Annual Conference, Washington, D. C., May 4-6 %D 1970 %T 840. Balancing Options in Aircraft Configuration Design %A Sanders, K L %A Nevinger, D O %K 10. Weight Engineering - Aircraft Design %X Several means of balancing an aircraft design are discussed herein. Equations are developed to determine required configuration changes and to analyze the associated weight penalties. A hypothetical fighter aircraft was chosen as example to demonstrate the applicability of the suggested procedure and to compare the weight penalties resulting from several balance methods. %B 29th Annual Conference, Washington, D. C., May 4-6 %I Society of Allied Weight Engineers, Inc. %C Washington, DC %P 41 %8 5/4/70 %G eng %U https://www.sawe.org/papers/0840/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 0840 %1 Non-Member Price: $20.50; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20.5 %4 SAWE0840 %0 Conference Paper %B 28th Annual Conference, San Francisco, California, May 5-8 %D 1969 %T 730. A New Challenge for Weight Engineering at Boeing %A Parsons, S P %K 10. Weight Engineering - Aircraft Design %X The point of this paper will illustrated by dividing the presentation into (1) A review of that identifies the new challenges (2) meeting the challenges of reorganizing the Boeing Company to support the 747 program %B 28th Annual Conference, San Francisco, California, May 5-8 %I Society of Allied Weight Engineers, Inc. %C San Francisco, California %P 8 %8 5/5/69 %G eng %U https://www.sawe.org/papers/0730/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 0730 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE0730 %0 Conference Paper %B 28th Annual Conference, San Francisco, California, May 5-8 %D 1969 %T 782. Heavy Lift VTOL - Effect of Weight and Size on Productivity %A Fuller, J E %A Marquis, M L %K 10. Weight Engineering - Aircraft Design %B 28th Annual Conference, San Francisco, California, May 5-8 %I Society of Allied Weight Engineers, Inc. %C San Francisco, California %P 26 %8 5/5/69 %G eng %U https://www.sawe.org/papers/0782/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 0782 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE0782 %0 Conference Paper %B 28th Annual Conference, San Francisco, California, May 5-8 %D 1969 %T 783. V/STOL - A Weights Study of Various Concepts %A Wisniewski, J S %K 10. Weight Engineering - Aircraft Design %B 28th Annual Conference, San Francisco, California, May 5-8 %I Society of Allied Weight Engineers, Inc. %C San Francisco, California %P 33 %8 5/5/69 %G eng %U https://www.sawe.org/papers/0783/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 0783 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE0783 %0 Conference Paper %B 27th Annual Conference, New Orleans, Louisiana, May 13-16 %D 1968 %T 705. Concorde %A Francis, J %K 10. Weight Engineering - Aircraft Design %X In presenting this paper on the Concorde – an aircraft which is such an advance on existing subsonic civil aircraft and which is also in an advanced state of construction – certain difficulties are encountered. The major one being that many articles have already produced on the aircraft and the problems is to judge what to include again. The purpose of the is paper is to provide an overall picture of the project and it will include such things as the control exercised by the British and French Governments, where the airplanes fit into the picture, how and where the aircraft is being designed and manufactured, etc. This is not the place to make controversial statements about the need to have supersonic, as opposed to very special “cheap fare”, aircraft. What can be said is that whenever a faster and more convenient from of transport becomes available it is always used. Throughout history there has always been, and always will be, the urge to reduce time spent on journeys. Figure 1 shows that there is relationship between growth of population and the length of a day’s journey. Very little progress was made prior to the early 19th century when a day’s travel covered anything up to 50 miles. Then a sharp increase in population was accompanied by a big jump in the journey length and in 50 years it increased to about 500 miles in a day. At t0-day’s rate of progress one hesitates to predict what will happen in 50 years from now. %B 27th Annual Conference, New Orleans, Louisiana, May 13-16 %I Society of Allied Weight Engineers, Inc. %C New Orleans, Louisiana %P 36 %8 5/13/68 %G eng %U https://www.sawe.org/papers/0705/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 0705 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE0705 %0 Conference Paper %B 26th Annual Conference, Boston, Massachusetts, May 1-4 %D 1967 %T 624. The Augmentor Wing - A New Approach to Jet STOL %A Conway, J A %K 10. Weight Engineering - Aircraft Design %X With the volume of commercial air traffic steadily increasing, a hard look is being taken at the ground time and runway facilities involved in air travel, with serious consideration being given to city to city centre operation, utilizing small available areas. The military, concerned with forward base supply and limited field lengths, are also investigating similar operations. Propeller driven aircraft have been developed to operate from short fields and currently medium sized transport aircraft are demonstrating excellent capabilities in this type of operation and recent exercises have established the value of vehicles having the ability to take off and land with high path angles and low speed. However, it is generally accepted that in the future, economic and tactical necessity will require these capabilities to be combined with cruise performance comparable with conventional jet aircraft. STOL capability is largely a function of low speed and relatively straightforward high lift systems can be applied which will reduce field length requirements to approximately 2,000 ft. However, to reduce these distances to those acceptable for true STOL, that is 1,000 ft or less, while maintaining stability and control, handling and safety characteristics, new and more sophisticated approaches will be required. The de Havilland Company has been engaged in an extensive program to develop one such system and this, together with other arrangements, is discussed. %B 26th Annual Conference, Boston, Massachusetts, May 1-4 %I Society of Allied Weight Engineers, Inc. %C Boston, Massachusetts %P 19 %8 5/1/67 %G eng %U https://www.sawe.org/papers/0624/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 0624 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE0624 %0 Conference Paper %B 25th Annual Conference, San Diego, California, May 2-5 %D 1966 %T 558. Design Considerations in the Boeing 737 Jet Transport %A Mack, P G %A Abrams, D W %K 10. Weight Engineering - Aircraft Design %X At a time when the industry trend in jet transport design has been toward aft body mounted engines and when The Boeing Company had recently introduced the highly successful Model 727, the same Boeing team, has designed the new twin-jet Model 737 with engines mounted on the wing. The factors that prompted this seemingly reactionary move, and some of the other significant design features of the 737, are the subject of this paper. To develop this subject, we will examine the engine location, engine selection, body cross section, and high-lift system that contribute to the advanced design of the 737. %B 25th Annual Conference, San Diego, California, May 2-5 %I Society of Allied Weight Engineers, Inc. %C San Diego, California %P 20 %8 5/2/66 %G eng %U https://www.sawe.org/papers/0558/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 0558 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE0558 %0 Conference Paper %B 25th Annual Conference, San Diego, California, May 2-5 %D 1966 %T 563. Introduction to the Gyroplane %A Crane, J F %K 10. Weight Engineering - Aircraft Design %X The major goal of Saalfeld Aircraft today is the accomplishment of obtaining Federal Aviation Authority certification for its new gyroplane before the end of this year. Many techniques must be resolved and many problems solved before the SKYSKOOTOR can be placed on the market. A brief description of flight principles is included to familiarize those not directly associated in the gyroplane industry with the mechanics of operation and major considerations. The important part played by weight and balance in the design of the SKYSKOOTOR is highlighted. Solutions to problems affecting gyroplane flight and stability are discussed. A section of this paper is assigned to auto rotation which provides an insight into the controls employed to use the aerodynamic forces which are independent of the torque forces inherent in the helicopter configurations. Close center of gravity tolerances require overhead balancing methods after weight calculations for final accurate simulation of flight prior to take-off. The determination and methods used to calculate the center of gravity and to balance the craft are presented in detail. Gyroscopic effects on weight and balance, private and commercial potential, and a new method to aid C.G. variables are also included. %B 25th Annual Conference, San Diego, California, May 2-5 %I Society of Allied Weight Engineers, Inc. %C San Diego, California %P 37 %8 5/2/66 %G eng %U https://www.sawe.org/papers/0563/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 0563 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE0563 %0 Conference Paper %B 25th Annual Conference, San Diego, California, May 2-5 %D 1966 %T 582. Moonlighting Mainliner %A Wallace, S R %K 10. Weight Engineering - Aircraft Design %X The B-727 QC, which stands for “Quick Change”, is a new innovation in aircraft utilization and was developed by United Air Lines and the Boeing Company. The QC provides standard passenger accommodation during the daytime and a palletized cargo aircraft at night. Innovations in ground equipment to accommodate the aircraft interior were developed by United Air Lines Engineers with the Food Machinery Corporation and will permit unloading the seats of an entire aircraft in less than 20 minutes. The aircraft and ground equipment meet the highest requirements f or passenger and cargo interiors. %B 25th Annual Conference, San Diego, California, May 2-5 %I Society of Allied Weight Engineers, Inc. %C San Diego, California %P 32 %8 5/2/66 %G eng %U https://www.sawe.org/papers/0582/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 0582 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE0582 %0 Conference Paper %B 25th Annual Conference, San Diego, California, May 2-5 %D 1966 %T 589. Payload and Loadability Improvements With the Convair/Dart Conversion %A Caddell, W E %A Benson, R L %K 10. Weight Engineering - Aircraft Design %X During the past ten years or so the Regional Airlines have experienced, a rather phenomenal and gratifying growth. This has been good for the trunk lines as well as for the traveling public in general. But this growth, like all other forms of progress, has generated its share of problems for the Regional operators. The increase in traffic has called for aircraft which provide (1) increased capacity both in passengers and cargo, (2) increased speed in order to improve their competitive position with surface travel, and (3) lower break-even load factors as capacity increases. The operators have done an admirable job of maintaining service with their DC-3’s of three decades vintage, but have been forced to obtain more modem equipment. Many of then have been replaced by Convair Liners and other aircraft which have, in turn, been replaced in trunk service by larger aircraft. This first step improvement has been accompanied by a further increase in traffic, has improved the payload capability, provided pressurized comfort for the passengers, and improved the cruise speeds to some extent. These aircraft, however, have still not filled their needs by any means. There is still a need for considerable improvement in these factors, as well as operating costs, to permit economical operation over routes of low density traffic. %B 25th Annual Conference, San Diego, California, May 2-5 %I Society of Allied Weight Engineers, Inc. %C San Diego, California %P 12 %8 5/2/66 %G eng %U https://www.sawe.org/papers/0589/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 0589 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE0589 %0 Conference Paper %B 24th Annual Conference, Denver, Colorado, May 17-19 %D 1965 %T 471. Parametric Approach to Aircraft Sizing and Trade-Off Studies %A Leavy, G C %K 10. Weight Engineering - Aircraft Design %X A parametric approach to aircraft sizing and trade-off studies has been developed to aid the design effort. It is particularly valuable for use in the design of V/STOL aircraft, where the choice of propulsion systems is wide and it is necessary to arrive at an early selection of an optimum propulsion system/airframe configuration and airplane size. This paper outlines an engine selection and airplane preliminary sizing procedure and its application to comprehensive weight trade-off studies, The unique weight estimation procedure used to predict the fuel available data, which is a key step, is discussed in detail. The fuel weight available is defined as the difference between the airplane take-off gross weight and the weight empty plus useful load. The procedure permits the estimation of the airplane weight empty in a parametric fashion over a wide range of variables without requiring the definition of the variables by drawing board layout. The weight estimation procedures have been programmed for accomplishment on digital computer facilities, thereby permitting rapid investigation of a large number of cases. The ability of this computerized approach to reflect the influence on airplane weight of the many parameters affecting airplane design is illustrated, including the determination of fuselage size based on a packaging concept. The use of this parametric approach makes it possible to evaluate a large number of propulsion system and airframe configurations rapidly and comprehensively prior to the design stage. This facilitates the design effort, since, at the beginning of the design stage, the area of choice has been narrowed and the weights engineer, as well as the other members of the design team, is provided with a vast amount of weight growth, weight penalty, and trade-off data pertinent to the design and performance of the aircraft. %B 24th Annual Conference, Denver, Colorado, May 17-19 %I Society of Allied Weight Engineers, Inc. %C Denver, Colorado %P 23 %8 5/17/65 %G eng %U https://www.sawe.org/papers/0471/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 0471 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE0471 %0 Conference Paper %B 23rd National Conference / Sheraton, Dallas Hotel, Southland Center, Dallas, Texas May 18-21 %D 1964 %T 338B. Evaluation of Economics of Passenger Comfort Standards (Part II) %A Mitchell, R G %K 10. Weight Engineering - Aircraft Design %B 23rd National Conference / Sheraton, Dallas Hotel, Southland Center, Dallas, Texas May 18-21 %I Society of Allied Weight Engineers, Inc. %C Dallas, Texas %P 9 %8 5/18/64 %G eng %U https://www.sawe.org/papers/0338B/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 0338B %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE0338B %0 Conference Paper %B 23rd National Conference / Sheraton, Dallas Hotel, Southland Center, Dallas, Texas May 18-21 %D 1964 %T 418. A Digital Computer Program for Fuel Tank General Design and Analysis %A Patterson, R W %K 10. Weight Engineering - Aircraft Design %B 23rd National Conference / Sheraton, Dallas Hotel, Southland Center, Dallas, Texas May 18-21 %I Society of Allied Weight Engineers, Inc. %C Dallas, Texas %P 22 %8 5/18/64 %G eng %U https://www.sawe.org/papers/0418/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 0418 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE0418 %0 Conference Paper %B 23rd National Conference / Sheraton, Dallas Hotel, Southland Center, Dallas, Texas May 18-21 %D 1964 %T 431. SST Weight Sensitivity %A Brown, E M %K 10. Weight Engineering - Aircraft Design %X It is not the intention of this paper to go into all of the details involved in a weight and balance analysis of the 727 airplane. Almost all of these facts are no different than any other airplane we have operated. However, the fuel system, and the attendant fuel management, does present a new twist, a t least to United Air Lines, and so is considered deserving of some discussions. It is this area of the weight and balance analysis with which this paper is concerned. The following pages are excerpted from the United Air Lines report which was compiled prior to certification in support of our operation of the airplane. Basic data relative to the fuel system, sample calculations, and the findings or conclusions of the report are presented. It should be noted that some of the numbers have been revised since the report was written and the airplane has been in operation. However, the method of analysis has not changed. %B 23rd National Conference / Sheraton, Dallas Hotel, Southland Center, Dallas, Texas May 18-21 %I Society of Allied Weight Engineers, Inc. %C Dallas, Texas %P 16 %8 5/18/64 %G eng %U https://www.sawe.org/papers/0431/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 0431 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE0431 %0 Conference Paper %B 22nd National Conference, St. Louis, Missouri, April 29 - May 2 %D 1963 %T 414. Weight Computations in Development Design %A Rogers, N %K 10. Weight Engineering - Aircraft Design %X Engineering Weight Control is gaining importance in space package designs because of the weight influence upon the performance characteristics of space vehicles. One phase of this function involves the preparation of periodic Weight Status Reports that are accurate and informative. To satisfy these needs a large volume of data must be processed during development design activity. Normally, this involves an appreciable manpower expenditure in computation effort. The use of an electronic computer can substantially reduce the computation work load. This paper describes an IBM Owego 7090 Weight Program that was designed to perform specific weight calculations and to process input data for publishing a Weight Status Report. %B 22nd National Conference, St. Louis, Missouri, April 29 - May 2 %I Society of Allied Weight Engineers, Inc. %C St. Louis, Missouri %P 20 %8 5/29/63 %G eng %U https://www.sawe.org/papers/0414/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 0414 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE0414 %0 Conference Paper %B 21st National Conference, Seattle, Washington, May 14-17 %D 1962 %T 332. Weight and Balance Considerations for Supersonic Aircraft Design and Operation %A Heineman, W %K 10. Weight Engineering - Aircraft Design %X This paper was presented at the Twenty-first Annual National Conference of the Society of Aeronautical Weight Engineers at Seattle, Washington, May 14-17, 1962. The present widespread interest in supersonic transport aircraft has spawned a number of design studios, which, from the viewpoint of the weight engineer, appear to contain certain weight and balance inconsistencies. The intent of this paper is to point out, using available weight data, the current and predicted weight trends peculiar to supersonic designs, and in particular, the weight growth trends of supersonic transports. It is further intended to present supersonic weight and balance data, in a comparative manner, which may be used as guides, goals and measuring devices for supersonic aircraft designs of the future. Weight efficiencies of supersonic aircraft are falling below present subsonic designs, at similar payloads and gross weights, caused mainly by stringent system requirements added in the interests of safety, reliability, passenger comfort, and efficient operation. Desired supersonic range is obtained by using increasingly larger amounts of fuel for decreasingly smaller gains in weight efficiency. Thus, there is a rapid growth of gross weight with lesser gains in weight efficiency or ratio of gross weight to dry weight. Resulting gross weights can only be reduced by ingenious, light weight s structure and systems, and increased velocity-to-specific fuel consumption and lift-to-drag ratios. The balance problem has been found to be more important for supersonic aircraft than it was in subsonic designs; as a result, this problem must be studied in detail early in the configuration selection studies. As the aircraft approaches supersonic speeds, the aerodynamic center moves rapidly aft, and remains appreciably aft of subsonic aerodynamic centers, throughout supersonic flight. A nearly equal aft shift of airplane center-of-gravity is required to prevent the use of high trimming forces that result in increased supersonic drag. It is concluded that weight and balance considerations must be given accurate and specific attention early in the evaluation of supersonic designs, to preclude the waste and confusion caused by overly optimistic weight estimates, and to insure realistic airframe configurations. %B 21st National Conference, Seattle, Washington, May 14-17 %I Society of Allied Weight Engineers, Inc. %C Seattle, Washington %P 19 %8 5/14/62 %G eng %U https://www.sawe.org/papers/0332/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 0332 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE0332 %0 Conference Paper %B 21st National Conference, Seattle, Washington, May 14-17 %D 1962 %T 338A. Evaluation of Economics of Passenger Comfort Standards (Part I) %A Mitchell, R G %K 10. Weight Engineering - Aircraft Design %B 21st National Conference, Seattle, Washington, May 14-17 %I Society of Allied Weight Engineers, Inc. %C Seattle, Washington %P 30 %8 5/14/62 %G eng %U https://www.sawe.org/papers/0338A/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 0338A %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE0338A %0 Conference Paper %B 20th National Conference, Akron, Ohio, May 15-18 %D 1961 %T 289. Aircraft Optimization %A Sanders, K L %K 10. Weight Engineering - Aircraft Design %X This paper was presented at the Twentieth National Conference of the Society of Aeronautical Weight Engineers at Akron, Ohio, May 15 – 18, 1961. This paper discusses a method with which optimum aircraft configuration parameters can be identified. Aircraft performance is mainly affected by the wing parameters, wing loading, aspect and thickness ratio. Changing the wing shape and size will in turn affect; 1) Tail size, 2) Drag, 3) Useful load and/or gross weight. Weight and drag equations have been developed to be simultaneously used in aircraft performance analysis. Several typical examples are shown, the results of which are comparable to those optimization methods. These methods incorporate interrelated drag and weight effects. Design- point optimization of aircraft performance, wing shape and dimension can be quickly accomplished. The intent of this paper is to keep the designer from assigning arbitrary values to the principal parameters of a design. This is still frequently done, by referring to similar, known and built airplanes, or likewise, by looking at aircraft performance equation only. In other words, the performance of many present aircraft can still be improved by the awareness of engineers planning new aircraft designs. %B 20th National Conference, Akron, Ohio, May 15-18 %I Society of Allied Weight Engineers, Inc. %C Akron, Ohio %P 54 %8 5/15/61 %G eng %U https://www.sawe.org/papers/0289/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 0289 %1 Non-Member Price: $27.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 27 %4 SAWE0289 %0 Conference Paper %B 19th National Conference, Hollywood Roosevelt Hotel, Hollywood, California, May 16-19 %D 1960 %T 260. Turbinizing the S-55 %A Wachs, M A %K 10. Weight Engineering - Aircraft Design %X This paper was presented at the Nineteenth National Conference of the Society of Aeronautical Weight Engineers at Los Angeles, California, May 16 – 19, 1960. This paper compares a turbine engine-powered helicopter with its antecedent reciprocating engine-powered helicopter, wherein the fully developed major mechanical components of the reciprocating engine-powered helicopter are used in the new turbine-powered helicopter. This paper shows that not only is considerable weight saved in the turbine engines itself but also in the installation of the engine. These weight savings more than compensate for the weight added by the unique feature of an “amphibious” boat hull and therefore result in increased performance as well as utility. This paper also shows the large economies the operator will enjoy by virtue of high overhaul periods that can be recommended for the mechanical components at the outset, by virtue of their being fully developed on the previous reciprocating engine-powered helicopter. The advantage of rear drive turbine engines for helicopters of greater than 5000 pounds gross weight are outlined. %B 19th National Conference, Hollywood Roosevelt Hotel, Hollywood, California, May 16-19 %I Society of Allied Weight Engineers, Inc. %C Hollywood, California %P 18 %8 5/16/60 %G eng %U https://www.sawe.org/papers/0260/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 0260 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE0260 %0 Conference Paper %B 19th National Conference, Hollywood Roosevelt Hotel, Hollywood, California, May 16-19 %D 1960 %T 269. The Influence of Balance and Loadability on the Design of Commercial Passenger Transports %A Hopper, G R %K 10. Weight Engineering - Aircraft Design %X This paper was presented at the Nineteenth National Conference of the Society of Aeronautical Weight Engineers at Los Angeles, California, May 16 – 19, 1960. With the advent of the swept wing turbojet airplane, balance and loadability control in the preliminary design stage has become an increasingly important phase of weight engineering. Current designs of subsonic swept wing, multi-engined passenger transports present increasingly complex balance problems which require consideration early in the design. These problems arise from the highly swept wings, power plant mounted on the fuselage, multi-class loading conditions, and the many different interior arrangements and wide choice of optional equipment offered for any particular model. In view of these problems the weight engineer must attempt to influence the design so that the airplane will inherently have good balance and loadability. The purpose of this paper will be to illustrate in what areas and by what means the design can be changed to provide the most readily loadable airplane. No attempt is made to offer specific solutions of tools as these will vary with each particular problem. It is hoped that by pointing out the pitfalls, more effort will be placed on designing good balance and loadability into the airplane. %B 19th National Conference, Hollywood Roosevelt Hotel, Hollywood, California, May 16-19 %I Society of Allied Weight Engineers, Inc. %C Hollywood, California %P 14 %8 5/16/60 %G eng %U https://www.sawe.org/papers/0269/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 0269 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE0269 %0 Conference Paper %B 16th National Conference, Broadview Hotel, Wichita, Kansas, April 29 - May 2 %D 1957 %T 163. A Study to Promote Weight Control of Items Designed to Airframe Manufacturers Specifications %A Author, No %K 10. Weight Engineering - Aircraft Design %X The Special Projects Committee of the St. Louis Chapter, S.A.W.E. undertook to determine the present state of the art concerning weight control on items designed by vendors to airframe manufacturers specifications. This was accomplished by a survey questionnaire that was sent to 125 vendors and 50 airframe manufacturers. With the present trend toward the weapons system design concept and the consequent large percentage of the design work of a project being done by vendors, the need for a unified approach to the problem of weight control becomes critically evident. %B 16th National Conference, Broadview Hotel, Wichita, Kansas, April 29 - May 2 %I Society of Allied Weight Engineers, Inc. %C Wichita, Kansas %P 18 %8 5/29/57 %G eng %U https://www.sawe.org/papers/0163/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 0163 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE0163 %0 Conference Paper %B 15th National Conference, El Cortez Hotel, San Diego, California, April 30 - May 4 %D 1956 %T 132. The Utilization of Weight Data in Aerodynamic Analysis %A Knight, R E %K 10. Weight Engineering - Aircraft Design %X This paper deals with the utilization of weight data in aerodynamic analysis. The word ‘weight” also includes the determination of the center of gravity locations and the effects of weight distribution, which are handled in the forms of moments of inertia and products of inertia. … This paper attempts to show the interdependence between the entire field of aerodynamics and weights. It is hoped that it may be both beneficial in clarifying the need for weight data by the Aerodynamicist, and that it may be effective in forming a bond of mutual understanding between the two groups for more efficient aeronautical design in the years ahead. %B 15th National Conference, El Cortez Hotel, San Diego, California, April 30 - May 4 %I Society of Allied Weight Engineers, Inc. %C San Diego, California %P 31 %8 4/30/56 %G eng %U https://www.sawe.org/papers/0132/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 0132 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE0132 %0 Conference Paper %B 14th National Conference, Hilton Hotel, Fort Worth, Texas, May 2-5 %D 1955 %T 114. Why Weight ! - The Relationship of Weight Control and the Designer %A Bingham, K %K 10. Weight Engineering - Aircraft Design %X “Weight control is a waste of time and money”--------------------------- Last Fall I heard a Designer in our company make this statement in a spell of anger during a weight-saving campaign on a current project. I argued the point with him, saying that, as the very least of reasons, it was a good way to keep designers weight-conscious. He resisted this point very strongly, saying that he was very weight conscious. To check this point, I asked several other designers if they were or were not weight conscious. Much to my surprise, I could not find a single one who would admit that he was not extremely weight conscious. So, for the record, all designers are weight conscious, -I have their word for it. If you should ever find on that admits he is not, please let me know. Incidentally, if this man is not weight conscious, what would he be, weight unconscious? When I was asked to prepare this paper, these thoughts came back to me. They started me thinking as to the basic relationship between weight control and airplane design. The following paper addresses several questions to keep in mind: 1. How important is weight control, really? 2. Is it a clerical or engineering function? 3. When did weight control start and why? 4. What function does it exercise, today? 5. What do I, as a designer, expect it to do for me? 6. What does engineering management expect from weight control? 7. Where is it going? What will it be next year? 5 years from now? 10 years from now? %B 14th National Conference, Hilton Hotel, Fort Worth, Texas, May 2-5 %I Society of Allied Weight Engineers, Inc. %C Fort Worth, Texas %P 18 %8 5/2/55 %G eng %U https://www.sawe.org/papers/0114/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 0114 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE0114 %0 Conference Paper %B 12th National Conference, Seattle, Washington, May 18-21 %D 1953 %T 80. Weight Problems in British to American Design Conversion %A Walters, R C %K 10. Weight Engineering - Aircraft Design %X The decision to build a British plan in America and the selection of The Glen L. Martin Company, under license to the English Electric Company to make the conversion a now a matter of history. The English Electric Canberra, design as a high altitude light bomber for the Royal Air Force has been converted into a effective night intruder airplane capable of being produced in larger quantities in American aircraft plants. The speed, high maneuverability and general configuration of the Canberra madi it very adaptable to its new role. This couple with the fact that it was an existing design capable of being put into mass production at a relatively early date caused the USAF to regard it with favor. Naturally, many problems are anticipated in a transition of this type and many arise which result in design changes to the aircraft. As in the design of any aircraft, a goal must be defined and a philosophy of design established at a very early date in order to produce the desired product. The targets set before the Martin Engineering staff were; (1) to make the Canberra effective as a night intruder; (2) to retain the characteristics of the Canberra which made it producible in quantity by our methods and (4) to accomplish the conversion as economically as possible. %B 12th National Conference, Seattle, Washington, May 18-21 %I Society of Allied Weight Engineers, Inc. %C Seattle, Washington %P 28 %8 5/18/53 %G eng %U https://www.sawe.org/papers/0080/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 0080 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE0080 %0 Conference Paper %B 11th National Conference, Buffalo, New York, May 5-8 %D 1952 %T 75. Designing Weight Out of the B-36 %A Pence, R F %K 10. Weight Engineering - Aircraft Design %X In the spring of 1940, at the time of the fall of France, the fate of available bases in Europe appeared to hang by a slender thread. The United States Air Force consequently envisioned the possibility of having to strike Germany from a base on this continent. Late in 1940 the basic performance requirements for an intercontinental bomber to carry out this mission were established and several aircraft companies were asked to bid on the project. The proposal submitted by Consolidated Aircraft was approved and the contract for the XB-36 was signed near the end of 194l. The original design mission for the airplane was the often quoted range of 10,000 miles carrying 10,000 pounds of bombs dropped at mid-range, with sufficient speed, altitude, and defensive armament to enable the bomber to perform its missions with a minimum degree of vulnerability. The ability to carry large tonnage bombs for shorter ranges was an important secondary objective. %B 11th National Conference, Buffalo, New York, May 5-8 %I Society of Allied Weight Engineers, Inc. %C Buffalo, New York %P 17 %8 5/5/52 %G eng %U https://www.sawe.org/papers/0075/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 0075 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE0075 %0 Conference Paper %B 8th National Conference, Dayton Biltmore Hotel, Dayton, Ohio, May 23-26 %D 1949 %T 32. Weight and It's Effect on the Operation and Performance of Commercial Aircraft %A Stern, J A %K 10. Weight Engineering - Aircraft Design %X The prime purpose of an airline is to carry the maximum payload possible at a profit in accordance with the rule of three: 1. Safety. 2. Passenger comfort. 3. Schedule dependability. This paper will briefly outline the problems that face an airline in utilizing the payload potential of its equipment to a maximum. To achieve this goal severa1 closely related parameters must be considered: 1. Various types of payload. 2. Takeoff, landing, and zero fuel weights. 3. The increase of the weight empty vs. improved safety and revenue generating capacity of the airplane. 4. Methods of utilization of the weight payload. 5. Center of gravity limits. It must be stressed that these variables are inter-related, and collectively determine the payload that can be carried over a route segment under any set of conditions -- some restricted payload at one time; others at another. To illustrate this situation typical route analyses will be made. %B 8th National Conference, Dayton Biltmore Hotel, Dayton, Ohio, May 23-26 %I Society of Allied Weight Engineers, Inc. %C Dayton, Ohio %P 22 %8 5/23/49 %G eng %U https://www.sawe.org/papers/0032/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 0032 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE0032 %0 Conference Paper %B 8th National Conference, Dayton Biltmore Hotel, Dayton, Ohio, May 23-26 %D 1949 %T 37. Weight Advantages of Flying Wing Aircraft %A Meyer, F J %K 10. Weight Engineering - Aircraft Design %X When comparing flying wing aircraft or all-wing aircraft to conventional aircraft, it is necessary, due to lack of other comparable data, to use the Northrop Flying Wing Bomber as a basis of all wing aircraft. The Northrop B-35 has a wing area of 4,000 sq. feet, a span of 172 feet, and a design gross weight of 206,000 pounds. The power plant consists of four Wasp R-4360 engines turning, by means of drive shafts and remote gear boxes, counter-rotating propellers. The preliminary design of this airplane was started in 1942 and the airplane was first flown in June of 1946. The B-35 is not considered a pure flying wing aircraft as all items necessary for flight are not accommodated within the airfoil section. The aircraft has such protuberances as the pilot’s enclosure, gun turret domes, drive shaft and gear box housings and the aft crew nacelle. However, it is a near approach to the ideal and will afford a good basis for comparison. The primary aim in the development of the flying wing aircraft by the Northrop Corporation was to improve the structural, as well as the aerodynamic efficiency of the airplane. That this aim has been accomplished can be shown by a comparison of the weights of the B-35 to the present day bombardment type airplane. %B 8th National Conference, Dayton Biltmore Hotel, Dayton, Ohio, May 23-26 %I Society of Allied Weight Engineers, Inc. %C Dayton, Ohio %P 6 %8 5/23/49 %G eng %U https://www.sawe.org/papers/0037/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 0037 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE0037 %0 Conference Paper %B 8th National Conference, Dayton Biltmore Hotel, Dayton, Ohio, May 23-26 %D 1949 %T 39. Pilotless Aircraft Weight Problems %A Roberts, E E %K 10. Weight Engineering - Aircraft Design %X In the comparatively recent past the rise of pilotless aircraft in the field of military tactics has necessitated many changes in the thinking of designers and engineering organizations. The technical vocabulary has been forced to accept new nomenclatures, new applications have been discovered for old laws of physics, and personnel has had to adapt itself to new and often startling concepts of design. These innovations have created the need for highly trained personne1 from related fie1ds -- mathematicians for computation of optimum launching ang1e and trajectories, thermodynamicists for heat and airflow problems, chemists for investigating fuel efficiencies, electronics experts for telemetering and guidance equipment, physicists to conduct research into the upper-air strata, and many other students of the applied sciences. Together with this introduction of personnel heretofore more distantly related to the aircraft industry has come an accompanying step-up in the pace of those designers, aerodynamicists, structural and weight control engineers normally considered an integral part of the engineering organization. It is with the latter group only that this discussion will be concerned, and an attempt will be made to point out some of the problems confronting the weight engineer, together with suggested solutions as dictated by actual experience covering a period of the last four or five years. This analysis will study first, estimating procedures, second, the weight control program, and, third, the special problems of actual weight and balance. %B 8th National Conference, Dayton Biltmore Hotel, Dayton, Ohio, May 23-26 %I Society of Allied Weight Engineers, Inc. %C Dayton, Ohio %P 9 %8 5/23/49 %G eng %U https://www.sawe.org/papers/0039/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 0039 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE0039 %0 Conference Paper %B Reprint of Article Appearing in the October 15, 1941 Issue of AMERICAN AVIATION %D 1941 %T 12. Weight Control - Aircraft Design Problem %A Foley, E J %K 10. Weight Engineering - Aircraft Design %X Among the more recently developed and highly specialized fields of aeronautical engineering is that of aircraft weight control and reduction. If we go back 10 years, we will find that this activity, limited as it was, was then handled by anyone who happened to have a little time on his hands. And yet, today, we have the Society of Aeronautical Weight Engineers, a national organization of the specialists, doing intensive research and missionary work to accurately control aircraft weights with an eye to even the slightest reductions. %B Reprint of Article Appearing in the October 15, 1941 Issue of AMERICAN AVIATION %I Society of Allied Weight Engineers, Inc. %C , %P 4 %8 10/15/41 %G eng %U https://www.sawe.org/papers/0012/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 0012 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE0012 %0 Conference Paper %B National Aircraft Production Meeting of the Society of Automotive Engineers at Los Angeles, California, October 30 - November 1, 1941 %D 1941 %T 13. Will Accessories Impede Our Payload? %A Hackney, L R %K 10. Weight Engineering - Aircraft Design %X The purpose of this paper is to call to the attention of our aviation industry a serious problem which is confronting the airplane manufacturer. Its aim is to present this problem together with all the known facts and factors in an effort to enlist the help and cooperation of the accessory manufacturer and the subcontractor in arriving at a solution. %B National Aircraft Production Meeting of the Society of Automotive Engineers at Los Angeles, California, October 30 - November 1, 1941 %I Society of Allied Weight Engineers, Inc. %C Los Angles, California %P 8 %8 10/30/41 %G eng %U https://www.sawe.org/papers/0013/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 0013 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE0013 %0 Conference Paper %B 1st National Meeting, Hotel Van Cleve, Dayton, Ohio, February 25-28, 1941 %D 1941 %T 3. Aircraft Accessories - A Weighty Problem %A Roberts, E E %K 10. Weight Engineering - Aircraft Design %X The actual completed weight of today’s airplane, whether its intended function be mi1itry or commercial, is a vital factor not only in performance, but also in its utility to the customer. The answer to the question: “how much should it weigh?” is estimated by the weight engineer; “How much may it weigh’ is specified by the aerodynamicist; “How much must it weigh?” is determined by the design, the service, and the structural engineers; but the final weight when the finished article is put on the scales is a compromise answer to these and other important questions, and is the responsibility of practically every man in the organization. There are five basic engineering principles which enter into the design or the component parts of the airplane: (1) DESIGN, which requires the part to perform its function satisfactorily, to lend itself to economical service and maintenance, and to incorporate aerodynamic refinements where necessary for reduction of drag; (2) SAFETY, demanding structural strength and stiffness consistent with the purpose for which the craft is intended; (3) ECONOMY, which insists on efficient use of material to maintain a high strength/weight ratio; (4) PRODUCTION, requiring adaptability to modern production methods; and (5) COST, which establishes a control to insure a profit commensurate with the capital investment. To combine these principles into a single definition, it might be said that “The ideal airplane is one which furnishes maximum utility to the customer, achieves adequate strength with a minimum ‘expenditure of material, and which can be fabricated by production methods at a cost permitting a reasonable profit.” %B 1st National Meeting, Hotel Van Cleve, Dayton, Ohio, February 25-28, 1941 %I Society of Allied Weight Engineers, Inc. %C Dayton, Ohio %P 13 %8 2/25/41 %G eng %U https://www.sawe.org/papers/0003/buy %9 10. WEIGHT ENGINEERING - AIRCRAFT DESIGN %M 0003 %1 Non-Member Price: $20.00; Member Price: $10.00 Members: First 10 product downloads are Free. %2 10.00 %3 20 %4 SAWE0003