SAWE Tech Fair is almost here!

SAWE Blog - Sun, 2020-06-14 11:11

I’m very excited about the upcoming SAWE TECH Fair and Training. It’s only a week away! It’s the first time we’ve been able to offer an event with such affordable pricing and easy attendance. I’m hoping that if you haven’t signed up already, you will within this coming week. For details and registration go to

The TECH Fair has most all of the elements of our conferences without actually traveling to be together. We have special speakers, technical presentations, a forum discussion, vendor presentations, 5 training courses, 6 industry committee workshops, presentations of special awards, announcement of scholarship winners, and more. But the essential element is YOU! So please be sure to join us.

I want to thank the TECH Fair and Training planning committee for pulling this unprecedented event together so quickly and efficiently. Engineers are known for getting the job done, whatever it takes. And this is yet another example how talented, resilient, and resourceful our organization can be. The goal of the TECH Fair and Training is meet SAWE’s mission of providing technical exchange to the mass properties community. Please join us in completing
this goal with your attendance and participation.

Thanks – see you at the TECH Fair!
John Hargrave
SAWE President

Categories: SAWE Blog

DJI Drone Deadlift Test

SAWE Blog - Fri, 2020-06-05 10:31

Here’s a fun article. Got me thinking about new mission profiles from my #DJIMavicMini

DJI Mavic Air 2 can lift a lot more than its body weight
Categories: SAWE Blog

SAWE TECH Fair and Training: Question and Answer Session

SAWE Blog - Mon, 2020-06-01 13:17

Mass Properties Community,
I hope you’ve already heard the news, but if you haven’t, SAWE is holding a TECH Fair and Training Conference online starting June 22 that will run for 3 weeks!
Checkout for general information and registration.

We’ve designed the schedule to accommodate both US and European time zones. Also, we’ve spread the activities such that attendees can both attend the conference part of the day and take care of work the rest of the day.

This is a great opportunity to experience an SAWE International Conference without traveling, without extended time away from work, and at very affordable costs. The entire Technical Sessions, Forum discussion, Standards and Practices joint sessions, and Industry Committee Workshops (the first 2 weeks) are available at one low price of $199.
Five training courses are offered at all time low prices:
• AWBS $350
• Designing the Aircraft of the Future $600
• Structural Weight Optimization for Mass Properties Engineers $300
• Developing Basic Parametric Models $300
• Marine Vehicle Weight Estimating $300

This virtual conference is a first for SAWE. We’ll be using the Zoom tools to connect us all.
I want to invite everyone to join me in a pre-conference Zoom meeting to discuss details of the conference and answer any questions you may have.

Please join me and the TECH Fair and Training team this Wednesday, June 3rd, at 7am Pacific by using the link below. We’re looking forward to your participation.

SAWE Tech Fair and Training Q&A Zoom Meeting

John Hargrave
SAWE President

Download an Outlook Calendar meeting file (.ics) to add the SAWE Tech Fair and Training Q&A Zoom Meeting to your calendar:

Categories: SAWE Blog

Finder’s Fee for chapters recruiting a Corporate Partner or Company Member

SAWE Blog - Fri, 2020-05-29 02:56

APPROVED at the SAWE Board of Directors meeting on Saturday May 23, 2020 was the following proposal: “It is being proposed that the SAWE Inc offer a 25% one time “Finder’s Fee” to a chapter for enlisting a company to join/rejoin the SAWE as a Corporate Partner or Company Member for the first time or after at least a 3 year lapse. 25% coincides with the chapter portion of yearly individual membership dues. Web research has shown “Finder’s Fees” charged up to 35%. The 25% Finder’s Fee will be paid based on the first year dues of at least a 2 year stint as a CPCM at the same membership level or greater for years beyond the first year. The Finder’s Fee would be paid after the 2nd year dues are received. The recruitment of a new company to the SAWE membership will bolster both the local chapter and SAWE as a whole through increased participation toward the goals of the Mass Properties Engineering profession. A “Finder’s Fee” will incentivize chapters to increase efforts to gain new CPCMs as it will allow the chapter more capability to plan and host events such as a regional workshop / conference.”

Categories: SAWE Blog

Solicitation for Consensus Body Members – Flight Vehicle Coordinate Systems, ANSI/SAWE STD A-6

SAWE Blog - Sun, 2020-05-17 06:14

SA Layout Template (NY-FILEMAKER-18)

The second solicitation for Consensus Body members for development of ANSI/SAWE Standard A-6 has posted publicly at  ANSI Standards Action May 15, 2020, page 40. With a response end date of 6/14/2020. This is a Call for Members (ANS Consensus Bodies) notice for directly and materially affected parties who are interested in participating as a member of an ANS consensus body. You do not have to be an SAWE member to participate in this Consensus Body.

We are  particularly looking to achieve balance of the consensus body which is currently heavy with the category User-Government. Other categories are under represented and persons wishing to participate with one of those representations in mind are welcomed on a priority basis. Others are welcome to apply as well, The participatory categories are:

  • producer: the product design/developer typically the manufacturer of the product in question
  • user-industrial: Where the standards activity in question deals with an industrial product, such as steel or insulation used in transformers, an appropriate user participant is the industrial user of the product.
  • user-government: Where the standards activity in question is likely to result in a standard that may become the basis for government agency procurement, an appropriate user participant is the representative of that government agency.
  • general interest: where an overseeing interested party may participate or other possible participant not involved in producing, directly using, or acquiring the product as a government user

A current draft of the standard is available from the contact noted below:

SAWE (Society of Allied Weights Engineers)

Contact: Jeffrey Cerro, (757) 570-1386,;

NASA Langley Research Center, MS 451, 1 N. Dryden Street, B1209, Hampton, VA 23681

New Standard

BSR/SAWE STD A-06-202X, Standard Coordinate System for Reporting the Mass Properties of Flight Vehicles RP A-6 (new standard)

Stakeholders: Aircraft, space craft, launch vehicle developers, and users.

Project Need: The recommended practice needs to be updated to incorporate additional scope, update relevant aspects that have evolved since the last major update [1999], and also go through the ANSI process to provide accredited consensus across the industry. Specifically, the RP to be updated is to include the scope of inertia topics that have impacted the missiles and space industry in the past and possibly prevent possible issues in the future. Typically used coordinate systems have also evolved over time and the recommended references need to be expanded upon to be more relevant. Incorporating the proposed additional scope into the standard will allow mass properties engineers to reduce errors or technical challenges regarding inertias and also update the coordinate system and other reporting aspect to be more current with respect to daily practices in the industry.

This standard will provide coordinate system designations for flight vehicles and standards for the placement of flight vehicle mass, center of gravity, and inertia with respect to vehicle features. Launch, space, and atmospheric vehicles are included in this standard.

Categories: SAWE Blog

SAWE Tech Fair Flyer

SAWE Blog - Mon, 2020-05-11 07:07

We are excited to announce the SAWE Tech Fair, a three week virtual event! See the attached flyer for more information. Please share and save the dates! More information to come as everything becomes finalized.

Categories: SAWE Blog

How much does the ocean weigh?

SAWE Blog - Sun, 2020-05-10 12:42

Quick – how much does the ocean weigh?

Let’s say you’ve recently been spending a lot of time at home with a small child. You foolishly told them you can’t play right now because you’re busy doing important work calculating the weight of stuff. This has sparked their interest. And they won’t let go of that question.

Sigh. I don’t know how much the ocean weighs. I couldn’t even guess how many zeroes are in the number.

Or could I?

70% of the Earth’s surface is covered in ocean. I’ve watched enough nature shows to remember that’s about right. What would that surface area be? Let’s assume the Earth is a sphere (it’s not, but it’s close enough). What’s the formula for the surface area of a sphere? I don’t remember and my Weight Engineer’s Handbook is in the office. No matter – let’s assume Earth is a cube instead. I know how to find the surface area of a cube.

I know what you’re thinking – working from home with a hypothetical kid asking dumb questions all day has driven me bonkers. We can’t assume the Earth is a cube. But for this estimate we can. All I’m looking for is a number within a few orders of magnitude of reality. The difference between a sphere’s surface area and a cube’s (with the cube’s edge the same length as the sphere’s diameter) is negligible.

The surface area of a cube is six times the area of one side of height H, or 6xH². Since our cube’s height is the same as our sphere’s diameter, we need to know Earth’s diameter. Because “Apollo 13” is an awesome movie I know that a spacecraft in low Earth orbit moves about 17,500 miles per hour and takes 90 minutes to complete an orbit. That gives a circumference of 26,250 miles and a diameter of 8360 miles. Let’s call it 8,000 miles because I read somewhere that low Earth orbit is about 50 miles up, the Earth is rotating under the spacecraft and I’m kidding myself if I’m going to assume any precision in this calculation.

That gives us an ocean surface area on our Earth-cube of 70% x 6 x 8000² = 269 million square miles.

I don’t know the average depth of the ocean, but I know most of it’s deep. I’m guessing between one and ten miles because I heard “miles” and ocean depth mentioned together somewhere. Let’s say two miles deep. That gives us a total volume of 538 million cubic miles.

Every weight engineer knows the density of water – it’s 1 gram per milliliter. That’s fresh water – salty ocean water is denser, close enough. I remember it that way because I’m an expatriate Canadian and the metric system is a tenacious thing. No matter, I can convert. There are 454 grams in a pound (thanks, Canadian food packaging!), a milliliter is the same as a cubic centimeter and there are 2.54 centimeters in an inch. Put that all together and you get a water density of 0.036 lb/in³, or 9,181,017,236,653 pounds per cubic mile. Time for scientific notation: 9.2x10E11 pounds per cubic mile.

At a volume of 538 million cubic miles, our ocean weighs 4.9x10E20 pounds.

How did I do? According to the internet, “Earth’s ocean is made up of more than 20 seas and four oceans, weighing an estimated 1,450,000,000,000,000,000 short tons” – or 2.9x10E20 pounds.

There you go, kid. My estimate came within 2x the real value. That’s pretty good for starting out with no earthly idea!

This is called “Fermi approximation”, named after World War Two-era physicist Enrico Fermi, who was known for making good approximate calculations with little to no data. It’s a great way to get a quick rough guess before moving on to more precise methods.

My first boss when I was a brand new mass properties engineer used this method to devastating effect. He would send me off to spend days researching, interviewing designers and analysts, drawing sketches and running calculations to estimate the weight impact of a potential design change. When I returned, he would knock off an estimate in a few seconds that would invariably be within spitting distance of my hours of work. It was humbling, and I would ask him why he made me go to the effort. He’d say his method is quick, but now I have the data to back it up. He didn’t say it also made me a better mass properties engineer, by giving me a powerful tool to quickly understand the size of a thing, whether it’s a potential weight impact or the number of hours a task might take – or the answer to a childish question.

If you like hearing about the techniques, methods and experiences of other weight engineers, I encourage you to attend the 2020 SAWE Tech Fair, starting June 22. A wide range of technical presentations, industry seminars and training classes will be featured, all live and online, presented by your mass properties colleagues.

Categories: SAWE Blog

SAWE TECH Fair and Training – Save the dates

SAWE Blog - Tue, 2020-05-05 06:12

The first ever SAWE TECH Fair and Training will start June 22nd and run over a three-week period.  The first week will focus on Technical Presentations.  The second week will focus on Standards & Practices with two joint sessions and the Industry Committee workshops.  There will be five training courses filling out the schedule.  Also, we’ll have presentations from our SAWE exhibitor and sponsor community to update us on their latest products.

The detailed schedule and pricing will be finalized soon.  But we want to share that the TECH Fair will be a great opportunity at very good price.  In addition, we’re working the schedule to have a minimal impact on workdays.  The SAWE TECH Fair and Training will be a good value for your training budget.

I urge you to make plans to participate and please spread the word.

Here’s a preliminary line up of what’s coming at the online SAWE TECH Fair and Training.

Live, Online SAWE Training Courses to be offered

  • Automated Weight and Balance System (AWBS)
  • Designing the Aircraft of the Future
  • Marine Vehicle Weight Estimating Methodology
  • Structural Weight Optimization for Mass Properties Engineers
  • Developing Basic Parametric Methods

Technical Presentations Planned

  • Keynote Address:  Dr. Dan Raymer of Conceptual Research Corporation “Why Weight Engineers are So Dang Important, and Why Weights Engineers Get All the Blame”
  • Weight and Balance Challenges for Hybrid Electric Propulsion System
  • Hydrogen Fuel Cell Power System Weight Challenges in VTOL Aircraft
  • Folding Wings – Benefits in Aircraft Design Despite Local Mass Increase
  • Use of Mass Growth Allowance to Dynamically Manage Mass Risk
  • Rotorcraft Mass Assessment in an Integrated Design Framework
  • Development of the Mass Properties Certification Program
  • A Portable Device for Measuring the CoG: Design, Error Analysis and Calibration
  • Investigation of an On-board Weight and Balance System for a Helicopter Equipped with Skid Landing Gear
  • Theoretical and Experimental Evaluation of the Flexibility of the Test Rig on Inertia Property Measurement
  • Aft Perpendicular… an Afterthought
  • Finding the Balance Between Accuracy and Practicality In Deadweight Audits
  • Dynamic Computer Simulation of Aircraft Buoyancy
  • Class II & 1/2 Mass Estimation of Light Aircraft Composite Wings
  • CFRP Density Uncertainties and its Overall Mass Impact
  • Strategies for the Composite Stiffened Panel Topology Optimization for Minimum Weight
  • One fits all? A Comparison of Weight Estimation Methods for Preliminary Aircraft Design
  • Evaluation and analysis of applying a MBSE Approach for optimizing Mass Properties Parameters in Commercial Aircraft Design
  • Advanced Weight Forecasting Based on Physical/Mechanical Similarity of Components During Early Development of Land Vehicles, Aircraft and Spacecrafts
  • Forum discussion topic:  The Role of Statistics in Mass Properties Engineering

Standards & Practices

  • Status of Recommended Practices
  • Overview of Recommended Practice development process
  • Certification Development Participation and Review
  • Discussion of development of a standard passenger weight guideline for the FAA as a standard practice for airline usage
  • Review of RP’s A-7 and A-8
  • Military Aircraft Workshop (agenda pending)
  • Marine Workshop (agenda pending)
  • Missiles & Space Workshop (agenda pending)
  • Offshore Workshop (agenda pending)
  • Ground Vehicle Workshop (agenda pending)
  • Airline Affairs Workshop (agenda pending)
Categories: SAWE Blog

SAWE: “Together, Apart”

SAWE Blog - Wed, 2020-04-08 10:10

The world pandemic is presenting us all with new challenges in our daily lives.  It’s such a simple set of instructions to just stay home, practice social distancing, and wash your hands thoroughly and frequently.  By now we’ve all caught on to the items being hoarded and hopefully have found a way to cope with that.  Also, we’ve either found suitable face masks or learned how to make them ourselves.  I’m sure that we’re all watching “the numbers” as COVID-19 spreads around the world.  But these aren’t merely numbers – they are people, families, and friends.  The saying “it’s a small world” reminds us how connected we are in the world community.  We must become physically disconnected to combat the spread of this dangerous virus.

New phrases such as “Together, Apart” have emerged.  In other times this phrase would represent a riddle, but these days there’s no explanation needed.  Fortunately we have the ability to stay connected with family, friends, and work via many internet tools.

I want to give you an advance notice that your SAWE is currently working on what we’re calling SAWE Tech Fair.  It will be a series of online events beginning in late June.  The Tech Fair will include technical presentations, keynote speakers, forum discussions, Standard and Practice presentations, industry committee workshops, and several training courses.  This is an exciting opportunity to experience many of the usual conference activities without having to travel.  We are in the early stages of putting together the Tech Fair agenda and details.  But I want everyone to alert their management and co-workers of this upcoming event.  Online attendance will be both convenient and cost effective. 

Please keep in mind the many technical resources available to you through our website and that members get 10 free downloads per year.  Perhaps it’s a good time for you to download and read a few SAWE technical papers.  SAWE committees continue to meet via Zoom video telecoms (Executive, Technical, Standards and Practices, and Certification Development).  In fact our Board of Director’s meeting will be held online this May.  I encourage SAWE Chapters to stay connected by having meetings online as well.

Recently our Executive VP, Clint Stephenson, began our annual membership drive.  As you renew or sign up for SAWE membership, I hope you realize the value and opportunities available to you through participation and take full advantage. The SAWE worldwide community remains connected through our website and online tools.  These are stressful and difficult times for us all.  We’ll do our best to meet the challenge of being “Together, Apart” through the strength of our membership and Corporate Partners. 

Best regards to all,

John Hargrave

SAWE President

Categories: SAWE Blog

A message on membership in the SAWE from the President

SAWE Blog - Wed, 2020-04-01 11:30

Membership in the Society of Allied Weight Engineers (SAWE) affords you access to a vast library of mass properties technical papers, reference materials, industry standards, training courses and new processes, plus direct connections to products and services from our vendors. SAWE membership also includes our magazine (the Journal), monthly SAWE news bulletins, and blogs for forum discussion. SAWE membership is an opportunity to participate in evolving and maintaining industry standards for mass properties. It is a community of technical sharing as well as building personal connections and relationships.

SAWE is taking industry lead by developing a Mass Properties Certification Program to address quality, mentoring, and experience related forecast needs for tomorrow’s community of engineers. This exciting program will provide many advantages to engineers, companies, and customers throughout industry. Membership participation is key to this very important endeavor.

SAWE membership provides benefits and opportunities to help you stay current with the latest technologies, information, and development. The SAWE membership community is continually providing support to the mass properties engineering profession. Visit to review our many products and resources.

I encourage every mass property engineer to join SAWE and explore the opportunities for enhancing your engineering experience. We welcome your participation.


John Hargrave, President

Categories: SAWE Blog

Beware of ZoomBombing

SAWE Blog - Mon, 2020-03-23 10:51

With SAWE’s increased use of Zoom for online meetings, please beware of something called “ZoomBombing”. I’ve added some info on properly configuring your Zoom account to the SAWE Zoom Meetings page.

Please DO NOT publicly share any Zoom meeting details.  This article outlines some vulnerable settings that allow internet trolls to sabotage Zoom meetings with something called ZoomBombing.

After you have created a personal Zoom account, here are some settings to help prevent this:
IF you have the need to publicly sharing Zoom links where they could be discovered by trolls, be sure to change screen sharing to “Host Only” before a call starts. Some tips for other ways to protect your Zoom calls include:

  • Disable “Join Before Host” so people can’t cause trouble before you arrive.
  • Enabling “Co-Host” so you can assign others to help moderate.
  • Disable “File Transfer” so there’s no digital virus sharing.
  • Disable “Allow Removed Participants to Rejoin” so booted attendees can’t slip back in.
Categories: SAWE Blog

SAWE Houston Offshore Workshop report

SAWE Blog - Mon, 2020-03-23 09:51

The SAWE Houston Offshore Workshop 2020 was held on March 6th at Fluor Corporation’s offices in Sugar Land, Texas with gracious sponsorship of Fluor, Aker Solutions, SAWE Inc and BAS/ShipWeight. The workshop focused on the review of the SAWE Offshore Recommended Practices, a revision of the ISO 19901 for Offshore Weight Control and the proposed Offshore Handbook chapter to the SAWE Mass Properties Engineering Textbook. The Class Society (ABS) and SAWE presented the: Rule; Guideline; Guidance Note; Recommended Practice and ANSI Standard development process that each organization uses. The reviews started with the Project Proposal for the document, followed by discussions of the class, ISO or regulatory basis of the requirements, a development history of the current draft. The discussions that followed got right to the main points or one could say road blocks to completing the SAWE Recommended Practices. The documents and RPs included RP 0-3 Weighing, O-4 Reporting, O-7 In-Service Weight Control, the Handbook and Mass Properties Engineer Certification. The meeting minutes in the Offshore Industry folder under standards and practices Group Office on the SAWE website has more detail.

Categories: SAWE Blog