SAWE Ground Vehicle RP G-1:2018 Draft Available for Public Review

The Ground Vehicle Committee is requesting the help of the SAWE membership at large to review their Recommended Practice G-1:2018 “Mass Properties Control for Ground Vehicles”. This recommended practice was approved by the GV Committee at the International Conference in May, and is available for public review in the Standard Public Review forum at this link: https://www.sawe.org/technical/rp/publicreview

Comments and inputs, corrections, clarifications and such from the experts in the mass properties field will help to make this document a top quality publication from SAWE and enhance the high standard our communities’ recommended practices already achieve.

Thanks for your assistance!

Welcome to the SAWE – Presentation

Have you ever wanted more information to take to your management to support your Weight Engineering endeavors? Would you like to learn more about our society as it stands today?

Well Thanks to Mr. Damian Yanez of Gulfstream Aerospace Corporation, your wishes are now at your fingertips.

Navigate to

https://www.sawe.org/system/files/Welcome_to_SAWE_Company.pdf

and learn more. Use it to further your career, make a case for training, conference attendance, developing technical content, and even securing your company as a SAWE Corporate Partner.

Technical Input on In Service Weight Control

I thought I would start a thread on a topic of conversation, In Service Weight Control, from recent SAWE events. After a platform is put into operation, configuration changes take place throughout operation.  This must be kept track of for safe and successful operation.

What related experiences can you share?

I’ll start.  I perform Integrated Mass Properties analysis on the International Space Station (ISS).   I gather inputs from the International partners on Visiting Vehicles coming and going.  I gather inputs from our International partners on modules.  I gather inputs from our Configuration team as changes are made, for example moving Orbital Replacement Units (ORUs) from their storage location on ISS to their new location to support continued operation.  I verify the inputs make sense and question everything that doesn’t.

When you put it all together, you have analysis of the ISS at any given point in time needed to operate the ISS as it orbits our Earth every 90 minutes.

Consider sharing your experiences here, at a local chapter meeting, in a presentation / paper, and/or at a conference.

I am hoping this will be a catalyst to increased technical discussion.

Thanks.

Clint.

Standards & Practices Update

We are pleased to announce that RP A-11, Personnel Qualification Requirements Operational Weight and Balance Control for Military Aircraft, and RP A-13, Weighing Reconciliation Techniques for Military Aircraft, are being posted to the SAWE website.

RP O-1, Offshore Terminology, is awaiting final approval and will be posted to the website sometime in January.  It is the result of a series of 20+ meeting of members of the Offshore Industry Committee in Houston, TX.

A revised RP-8, Weight and Balance Data Reporting Forms for Aircraft (Including Rotorcraft and Air-Breathing Unmanned Vehicles), is awaiting final approval and will be posted to the website upon completion.

Project Proposals for RP M-4, Vendor Weight Control for the Marine Industry , and RP A-6, Standard Coordinate System for Reporting the Mass Properties of Flight Vehicles, to become ANSI-SAWE Standards have been posted as well.

More information on RP A-11: The purpose of this document is to provide a recommended set of requirements for qualifying civilian contractor personnel to perform weight and balance control activities/tasks on operational military aircraft. Those tasks include but are not limited to the completion of military aircraft weight and balance control system forms, the creation and maintenance of aircraft weight and balance handbooks, the creation and approval of aircraft weight and balance flight clearance forms and the actual measurement of the weight and balance (center-of-gravity) of military aircraft.

More information on RP A-13: The objective of this Recommended Practice is to document methods and practices that have proven effective in the reconciliation of significant differences between measured weight and balance values obtained from actual weighing measurements and predicted values. These proven methods are applicable to most military aircraft, including transport, fighter, and unmanned aircraft, and are applicable to weighings accomplished using a variety of measurement equipment including portable weighing platforms, permanently installed weighing platforms, and top-of-jack load cells. Procedures and calculations relating to applying measured data towards the end product of calculating Basic Weight and Center of Gravity are well established in other industry standards and are beyond the scope of this document. For example, it is not the intent of this RP to address the details of any aircraft’s weighing procedure, but rather to provide guidance on what to do if weighing results are significantly different from predicted.

More Information on RP O-1 : To insure consistency across all weight management documents, in a multinational and multicultural project such as an offshore oil industry project, a centralized Weight Management Definitions document has been created.  At the onset of each project, a similar, weight management specific, definitions document should be issued to clarify weight management terminology to be used on that project.  This document starts with weight management terms as defined in ISO 19901-5: 2003.  Additional terms commonly used for weight management but not defined by ISO are also defined herein and, to the extent possible, have been defined per their most common industry usage

As always, if you have any questions or wish to be involved in Standards and Practices please email standards@sawe.org

New Emphasis on Standards and Practices

Everyone reading this blog is involved in some way with mass properties – as an engineer, a technician, a manager, or sales. Every one of us has experience and knowledge that we could pass on to others involved in the mass properties world. Broadly speaking, this knowledge can be broken into two overarching categories – Technical Details and Methodologies.

Throughout its many years, the SAWE has concentrated on the first of these categories, asking mass properties personnel to spread their knowledge of technical details by writing papers, giving presentations, or teaching a class. We still want (and need) our practitioners to do this.

Paradoxically, the influence of the SAWE as an organization has grown while our individual influence has shrunk. Let me try to explain this. Several years ago, the SAWE became a Standards Organization by seeking and achieving recognition by the American National Standards Institute (ANSI). As a result, the society has gained a growing influence in both America and abroad. However, even as the society as a whole has gained recognition for our unique mastery of the science and art of mass properties concepts, our members have experienced erosion of the profession by those who employ mass properties personnel. Primarily this has been a consequence of ever more capable automated capabilities of computer programs. This has created a sense that what we as mass properties professionals can do can be duplicated by computer algorithms. This is not a new phenomenon. Forty years ago, when I was a fresh out of college new mass properties engineer, I heard the head of the mass properties group say, “Eventually, we’ll be able to push a button and the computer will spit out a new airplane design.” Implied in this was that we would not be needed.

I will be the first to admit that much of the calculation duties that were required all those years ago have been supplanted by Computer Aided Design programs, provided that the required parameters have been properly implemented. Calculating weight, CG, and inertias rarely gets performed by today’s mass properties engineers, except perhaps during early conceptual designs. Although this was a large part of my initiation into mass properties, there were many other aspects, including evaluating assembly drawings for completeness and crucially, compatibility. I have lost track of the number of supposedly connectable parts which obviously wouldn’t connect, missing parts, and even parts that shouldn’t be in an assembly and whose presence would preclude operation of the assembly I have found. And these were assemblies that had made it through the Checking group! This was never written down as part of my job description, but are errors I found that had to be corrected before I would accept an assembly into the database. These problems don’t disappear because a computer has calculated some numbers. It still takes a person looking at a project as a whole to find and solve these problems.

Which brings us to the second knowledge transfer category – Methodologies. The SAWE has an obligation to ensure that its members know what is required to perform as mass properties practitioners. The most effective means of performing mass properties tasks is to work through the task in an orderly fashion, so that we can be sure that nothing of importance is inadvertently missed. And the society has found that having a blueprint of what tasks are required is an effective aid. We call these task “blueprints” Standards if the “blueprint” conveys specific technical information that results in a consensus of how that information is presented. An example would be a standardized coordinate system used by a specific industry. How a standardized coordinate system is implemented is not included in the Standard. A Practice is the flip side of the coin regarding Standards – a Practice delineates the accepted means of performing a task. The SAWE designates a Practice as a Recommended Practice, such as SAWE RP A-3, 2016: Mass Properties Control for Space Vehicles. This RP defines what is accepted in industry to ensure that required mass properties tasks are completed and in useable form.

The SAWE has requested that mass properties practitioners consider writing a paper for the conference in Fort Worth in May, 2018 to address specific gaps in our Standards and Practices. Applicable papers do not need to be fully realized Recommended Practices or Standards, but should be utilizable as a framework upon such RPs or Standards could be taken up by our Industry Committees and turned into RPs or Standards (using our standardized templates). Specific areas of interest are delineated on the SAWE web site at https://www.sawe.org/technical/papers/2018Campain (yes “campaign” is misspelled in the URL). Please consider what you can contribute to the SAWE by helping us fill in the gaps in our Standards and Practices, and increase our visibility into Mass Properties Methodology. And if you know of specific Technical Knowledge, we will of course accept Technical papers as well. In either case, if you write a paper for the conference, please submit your abstract at http://www.sawe.org/technical/papers/submittal.