SAWE Technical Papers

@inproceedings{0014,

title = {14. Weight Predictor},

author = {C Merrell},

url = {https://www.sawe.org/product/paper-0014},

year  = {1941},

date = {1941-11-01},

booktitle = {Reprint of Article Appearing in the November, 1941 Issue of BOEING NEWS},

pages = {5},

publisher = {Society of Allied Weight Engineers, Inc.},

abstract = {Swami Anderson sits quietly at his table gazing intently at a three-view drawing. Occasionally he leans back and peers into the smoke rising from his pipe. He mutters softly to himself, 'Truss spar — monocoque – .064 skin pay load – rear gunner – twin tail —-'. 

Now and then he frowns and grabs his slide rule for a few quick calculations. Eventually he leans back easily in his chair and a look of satisfaction smoothes his furrowed brow. He has looked far into the future and is now about to predict the detailed weight of an airplane which is as yet only pretty picture. 

It isn't long, though, before his serenity is shattered. Soon the Sales Department's phoning from Washington, D.C. 

'Hey, listen,' a voice complains to Engineering, 'we're not selling aluminum. The customer wants some payload in this airplane. If you can't pare the weight down, we can't get the contract.'},

keywords = {11. Weight Engineering - Aircraft Estimation},

pubstate = {published},

tppubtype = {inproceedings}

}

@inproceedings{0011,

title = {11. The Messerschmitt 110 - Details of Germanys Mass Production Fighter},

author = {J E Thompson},

url = {https://www.sawe.org/product/paper-0011},

year  = {1941},

date = {1941-11-01},

booktitle = {15th Dinner Meeting of the Los Angeles Chapter, Western Division of the Society of Aeronautical Weight Engineers, Inc., Los Angeles, California, November 14, 1941},

pages = {7},

publisher = {Society of Allied Weight Engineers, Inc.},

address = {Los Angles, California},

abstract = {The Messerschmitt Me 110 long-range fighter is an airplane designed for 'blitzkrieg production' as well as blitzkrieg warfare. A brief examination reveals that its designers gave careful attention to the basic factors governing mass production practicability and economy - design simplification; e1imnation of close limits and clearances; practical assemblies, and installations; and a minimum variety or structural shapes and sheet gages. Examination reveals that this airplane lacks nothing that a high-grade military airplane should possess. Its performance is good; armament heavy; instruments and controls are adequate. Long and short-wave CW and phone radio equipment is provided. 

Production economy has largely been achieved by loosening up manufacturing limits as much as possible by ingenious design. Interchangeability of wing fillets is a troublesome prob1em in aircraft production, as it is necessary to hold close dimensional limits on the attachment screw holes in a part that is curved in three dimensions, and extremely flexible. This problem is solved by piercing large attachment holes in the fillet itself, and using attachment strips that clamp the fillet edges between strip and wing or fuselage. This design permits drilling of attaching screw holes in strips and wing or fuselage with matched drill-jigs to insure perfect alignment, and the large holes in the, fillet itself permit considerable dimensional variation of this part. 

A similar problem of dimensional variations between ring tips and panels is met by special washers, screwed down over attaching holes in the skin. The attaching holes in the tips are large enough to compensate for variations in the location of mating holes in either section of the wing. 

An unusual design permits considerb1e fore-and-aft and vertical adjustment of the nose-section wing fittings for alignment at final assembly. The fitting mounting face and pad are finely serrated, and the mounting bolt holes are oversize to permit adjustment of the fitting – with shear loads being transmitted through the serrations, rather that through the bolts.},

keywords = {30. Miscellaneous},

pubstate = {published},

tppubtype = {inproceedings}

}

@inproceedings{0013,

title = {13. Will Accessories Impede Our Payload?},

author = {L R Hackney},

url = {https://www.sawe.org/product/paper-0013},

year  = {1941},

date = {1941-10-01},

booktitle = {National Aircraft Production Meeting of the Society of Automotive Engineers at Los Angeles, California, October 30 - November 1, 1941},

pages = {8},

publisher = {Society of Allied Weight Engineers, Inc.},

address = {Los Angles, California},

abstract = {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.},

keywords = {10. Weight Engineering - Aircraft Design},

pubstate = {published},

tppubtype = {inproceedings}

}

@inproceedings{0012,

title = {12. Weight Control - Aircraft Design Problem},

author = {E J Foley},

url = {https://www.sawe.org/product/paper-0012},

year  = {1941},

date = {1941-10-01},

booktitle = {Reprint of Article Appearing in the October 15, 1941 Issue of AMERICAN AVIATION},

pages = {4},

publisher = {Society of Allied Weight Engineers, Inc.},

address = {,},

abstract = {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.},

keywords = {10. Weight Engineering - Aircraft Design},

pubstate = {published},

tppubtype = {inproceedings}

}

@inproceedings{0008,

title = {8. A Practical Method for Wing Weight Estimation},

author = {C R Englebry},

url = {https://www.sawe.org/product/paper-0008},

year  = {1941},

date = {1941-07-01},

booktitle = {13th Dinner Meeting of the Los Angeles Chapter, Western Division of the Society of Aeronautical Weight Engineers, Inc., Los Angeles, California, July 18, 1941},

pages = {15},

publisher = {Society of Allied Weight Engineers, Inc.},

address = {Los Angles, California},

abstract = {In this paper Mr. Englebry states the need of a relative quick and accurate method of estimating the weight of the wing consistent with design criteria. 

He outlines the effect of various items influencing the weight of the wing and develops a basic formula whereby all conditions are considered. 

A chart is given tabulating the information necessary to plot estimation curves for any particular of wing construction, whereby quick estimates can be made for wings of similar construction. Curves are plotted for wings constructed by Lockheed Aircraft Corporation. 

The problem of estimating wing weights is a very complex one, for no other major structural item of an airplane has so many varying factors that affect weight. There is a definite need for an estimating method, based on these varying factors that can be applied to any type of wing with reasonable accurate results. The attack of the problem must be based, however, on logic and be as simple as possible within the limits of reasonable accuracy. In other words, a compromise should be made between the simplest method of wing estimation, an estimate based on a similar model already constructed, and the most complex method, a complete stress analysis of the wing. 

The purpose of this article is to present a method of wing weight estimation that is logical, practical, accurate, and, although complex in its derivation, simple to apply. Basically, the method was evolved from an equation of the bonding material required to sustain the air loads. It is applicable to all types of airplanes, and accounts for weight variations due to wing loading, span, thickness, taper ratio, load factor, and material. This method is also adaptable for use with particular types of structure instead of particular types of airplanes. Essentially, this means that a broader scope of estimates can be made; for most modern airplanes employ similar typos of wing structure.},

keywords = {23. Weight Engineering - Structural Estimation},

pubstate = {published},

tppubtype = {inproceedings}

}

@inproceedings{0007,

title = {7. Predetermination of Weight Efficiency},

author = {D M Cole and S J Hutchinson},

url = {https://www.sawe.org/product/paper-0007},

year  = {1941},

date = {1941-05-01},

booktitle = {12th Dinner Meeting of the Los Angeles Chapter, Western Division of the Society of Aeronautical Weight Engineers, Inc., Los Angeles, California, May 23, 1941},

pages = {19},

publisher = {Society of Allied Weight Engineers, Inc.},

address = {Los Angles, California},

abstract = {The stress-weight ratio has often boon used to make such comparisons. This is permissible with the simpler types of loadings, such as pure tension or compression, but as more complicated 1oadings are encountered the ratio gives fallacious resu1ts. Some types of stresses depend entirely on the ratio of Young's Modulus to density, others on a function of the stress-weight ratio and a dimension. It can be seen from those facts that using only the stress-weight ratio for comparison does not always lead to a correct evaluation of the weight efficiency of a material.},

keywords = {23. Weight Engineering - Structural Estimation},

pubstate = {published},

tppubtype = {inproceedings}

}

@inproceedings{0010,

title = {10. Calculation of Landing Gear and Hydraulic System Weights},

author = {Harold W Adams},

url = {https://www.sawe.org/product/paper-0010},

year  = {1941},

date = {1941-05-01},

booktitle = {12th Dinner Meeting of the Los Angeles Chapter, Western Division of the Society of Aeronautical Weight Engineers, Inc., Los Angeles, California, May 23, 1941},

pages = {9},

publisher = {Society of Allied Weight Engineers, Inc.},

address = {Los Angles, California},

abstract = {In the first section of his paper Mr. Adams discusses the effect of hydraulic pressure on the weight of hydraulic systems. Graphs are then used to i1lustrate this re1ationship for various tubing sizes and materials. Another graph also shows the effect of pressure on weight of steel hydraulic cy1inders, and the weight penalty caused by impractical machining of thin wall cylinders. 

The second section presents simple methods of estimating weights of tires, wheels, and brakes. 

A method of calculating tire weights from known weights of geometrically similar tires is given in addition to methods of estimating weights for tires of unknown characteristics on the basis of load arid inflation pressure. 

Wheel weight estimates by moans of a constant for various typos of tires is another discussed. 

Weights of brake drums are calculated by determining heat input and amount of material necessary to absorb and dissipate this heat. Brake weights are estimated as a function of drum weights.},

keywords = {24. Weight Engineering - System Design},

pubstate = {published},

tppubtype = {inproceedings}

}

@inproceedings{0005,

title = {5. Relationship of Identification Numbers to Weight and Cost Control},

author = {D R Watson},

url = {https://www.sawe.org/product/paper-0005},

year  = {1941},

date = {1941-03-01},

booktitle = {2nd Dinner Meeting of the Philadelphia Chapter, Society of Aeronautical Weights Engineers, Philadelphia, Pennsylvania, March 31, 1941},

pages = {6},

publisher = {Society of Allied Weight Engineers, Inc.},

address = {Philadelphia, Pensyalvania},

abstract = {This discussion is intended to be helpful in achieving coordination of the various departments to save time and to obtain uniformity. Numbers are used for two important purposes, namely, to indicate a quantity and to identify. Both uses are extremely important to the Aircraft Weight Engineer. A number is used to indicate the weight of an article. A group of numbers is used to identify the article and each individual homogeneous piece of material used in its fabrication. The identification numbers may be merely serial or consecutive; or they may be selected numbers which have a two-fold purpose, namely, to servo as a classifying medium as well as a serial number. This paper is prepared to illustrate the inherent value of the latter.},

keywords = {17. Weight Engineering - Procedures},

pubstate = {published},

tppubtype = {inproceedings}

}

@inproceedings{0004,

title = {4. The Weight Engineer and the Flutter Problem},

author = {P E Bisch},

url = {https://www.sawe.org/product/paper-0004},

year  = {1941},

date = {1941-03-01},

booktitle = {11th Dinner Meeting, Melody Lane Cafe, Hollywood, California, March 14, 1941},

pages = {5},

publisher = {Society of Allied Weight Engineers, Inc.},

address = {Hollywood, California},

abstract = {Mr. Bisch first defines and illustrates several fundamental cases of vibration. An explanation of the particular case of vibration as set up in the flutter of wing or tail and how actual flutter is caused follows. 

The second phase of the paper is an outline of the information required by the flutter engineer from the weight engineer and how this may be obtained. 

An estimate for the time required to obtain the necessary weight data is given and this along with the procedure should prove very helpful when dealing with flutter problems.},

keywords = {22. Weight Engineering - Structural Design},

pubstate = {published},

tppubtype = {inproceedings}

}

@inproceedings{0006,

title = {6. The Present Status of Beryllium},

author = {L L Scott},

url = {https://www.sawe.org/product/paper-0006},

year  = {1941},

date = {1941-02-01},

booktitle = {1st National Meeting, Hotel Van Cleve, Dayton, Ohio, February 25-28, 1941},

pages = {11},

publisher = {Society of Allied Weight Engineers, Inc.},

address = {Dayton, Ohio},

abstract = {From the time in the early 1920's that metallic beryllium was first available in very small quantities in this country, the element has been surrounded with fantastic stories crediting it with almost unachievable properties. Being one of the lightest of the metallic elements; in fact occupying the fourth place of the periodic system, preceded only by hydrogen, helium and lithium and yet having a reputed modulus some thirty percent higher than steel, early experimenters made fabulous claims concerning its extraordinary virtues in light metal alloys. Reading one of the first United States patents pertaining to beryllium is enough to make a modern airplane designer's mouth water with anticipation. According to this patent dated March 16, 1920, beryllium could be readily melted with aluminum to form alloys of extreme lightness, combined with high rigidity, tensile strength and resistance to heat and oxidation, which were of great importance in construction of machines for aerial navigation: and for the moving parts of high speed mechanisms, such as for example, pistons of gasoline engines. The wondermetal, beryllium, was even said to alloy with lithium to make a high strength oxidation resistant and corrosion resistant alloy with a specific gravity of about 1.5. Amazing alloys of beryllium and magnesium were also claimed, which were to produce untold wonders in the mechanical world. 

Unfortunately, many of these loose statements have permeated the popular scientific literature on metallurgical subjects over the past fifteen years, and even today many persons not closely familiar with the subject think of beryllium as a mystery metal, currently used in some secret manner in the aviation industry. In 1930 one of the prominent engineering magazines stated that if beryllium was available in quantity, an airplane then carrying 4500 pounds of payload could carry 7550 pounds, or about l6 additional passengers. As late as February 1940, an article in the Los Angeles Times reported that any prospector finding a deposit containing 500.000 tons of recoverable beryllium ore could get a check for a million dollars from some airplane factory owner. 

As a matter of fact, it is not as a light metal, nor as an ingredient of light metal alloys that beryllium has achieved industrial prominence. Although the element does have a low specific gravity, approximately 1.8, and an indicated Young's modulus of elasticity in the order of 40,000.000 psi, the pure metal is still more or less a relatively expensive laboratory curiosity.},

keywords = {27. Weight Reduction - Materials},

pubstate = {published},

tppubtype = {inproceedings}

}

@inproceedings{0003,

title = {3. Aircraft Accessories - A Weighty Problem},

author = {E E Roberts},

url = {https://www.sawe.org/product/paper-0003},

year  = {1941},

date = {1941-02-01},

booktitle = {1st National Meeting, Hotel Van Cleve, Dayton, Ohio, February 25-28, 1941},

pages = {13},

publisher = {Society of Allied Weight Engineers, Inc.},

address = {Dayton, Ohio},

abstract = {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.'},

keywords = {10. Weight Engineering - Aircraft Design},

pubstate = {published},

tppubtype = {inproceedings}

}

@inproceedings{0015,

title = {15. Organization for Weight Control},

author = {J E Ayers},

url = {https://www.sawe.org/product/paper-0015},

year  = {1941},

date = {1941-01-01},

booktitle = {1941},

pages = {14},

publisher = {Society of Allied Weight Engineers, Inc.},

address = {,},

abstract = {From a study of how various aircraft manufacturers delegate and conduct weight control the writer herein sets forth an organization scheme for complete and efficient weight control over the design and manufacture of aircraft. With no more than slight modification the scheme is possibly adaptable to weight control over the design and manufacture of other craft and vehicles. 

In weight control, as in all other endeavor, the first step toward organization is to recognize the importance of organization. Control over weight does not just happen - it has to be planned and must be executed through proper channels. Where no organization for weight control exists there will be no control over weight. Even the cleverest weight engineer in the industry must have a prescribed routing for his ideas arid a system for getting them into effect that includes authority parallel to his responsibilities. 

A logical manner in which to plan an organization is to determine what is most important and then give each function a place in the scale deserving of its importance. In design there must be some supreme authority, therefore a chief engineer, or a vice-president in charge of engineering, is delegated with power to dictate policies and arbitrate major controversies within the engineering department. This chief engineering executive, or his delegated staff assistant, must be weight conscious and as equally sympathetic toward weight control as he is toward other engineering considerations, or no weight control can be exercised.},

keywords = {16. Weight Engineering - Organization},

pubstate = {published},

tppubtype = {inproceedings}

}

@inproceedings{0002,

title = {2. Airplane Weight and Balance Control},

author = {S Shatto},

url = {https://www.sawe.org/product/paper-0002},

year  = {1940},

date = {1940-07-01},

urldate = {1940-07-01},

booktitle = {16th Semi-Annual Engineering and Maintenance Conference Air Transport Association of America, Hotel St. Paul, St. Paul, Minnesota, July 15-17, 1940},

pages = {11},

publisher = {Society of Allied Weight Engineers, Inc.},

address = {St. Paul, Minnesota},

abstract = {(As taken from Part I of proceedings of Engineering and Maintenance Conference of the Air Transport Association of America at St. Paul, Minnesota on July 15, 16 and 17, 1940) 

I shall give you a resume of Weight Control Procedure which we have prepared by thoroughly studying some of the other operators and visiting airplane manufacturers. The importance of weight control has been very evident in the past few years; all operators are wanting to carry the maximum pay-load possible at all times. It is accurate weight control that makes it possible. 

The object of Weight Control, both from the viewpoint of the air carrier and from that of the Civil Aeronautics Authority, is the same, namely, to know at all times the actual load condition of the aircraft. It is true, however, that the reasons for requiring this information differ as considered by the Authority and the air carrier.},

keywords = {03. Center Of Gravity},

pubstate = {published},

tppubtype = {inproceedings}

}

@inproceedings{0001,

title = {1. Weight Economy},

author = {J E Ayers},

url = {https://www.sawe.org/product/paper-0001},

year  = {1940},

date = {1940-03-01},

booktitle = {5th Dinner Meeting of the Society of Aeronautical Weight Engineers at Santa Monica, California, March 15, 1940},

pages = {12},

publisher = {Society of Allied Weight Engineers, Inc.},

address = {Santa Monica, California},

abstract = {This discussion is intended to be helpful in achieving a maximum of weight economy. 

On the following page is a check-off list that could be applied, in part or in its entirety, to each drawing before release. 

A short discussion of the items of the check-off list follows in the succeeding pages. To facilitate cross reference the divisions of the discussion are identical with the subject items of the check-off list.},

keywords = {22. Weight Engineering - Structural Design},

pubstate = {published},

tppubtype = {inproceedings}

}