Success in Weight Control

In 1986 I was seemingly drifting from project to project on a short-term basis when I was asked to report to a program known only as Program B.  I arrived at the locked door on the fifth floor of a building we jokingly referred to as “The Six Story Building”.  After knocking on the door, I was greeted by a secretary who looked at my badge, checked my name against a list, and let me in.  I was shown a desk, where I dropped my briefcase, and then followed the secretary to what proved to be the program manager’s office.

Inside, there were a small group of people standing around.  The secretary left and came back a few minutes later with another person.  This continued for about 15 minutes, then a slight, balding man arrived and shut the door.  He introduced himself as the program manager, whom I will call Doctor E.  Doctor E went around the room asking each of us to state our names and areas of expertise.  Then he explained what we were doing.

The government was looking to launch a satellite that would use an infrared device, cooled by a Dewar jar filled with liquid methane.  We were to design this satellite, incorporating the various instruments and this quite large and heavy Dewar.  And then we were hit with the kicker – the launch vehicle was already designated, and it did not have a large payload capacity.  And the deployment stage would spin for stabilization.

I went back to my desk and began listing what this satellite would need – structure, electronics, tubing, cabling, power, etc., and going over the specs we had been given for the instrumentation and the Dewar.  Then I conceptually created a satellite and came up with a weight estimate that I took to the structures lead.  He called in the thermodynamics engineer to look at what I had come up with just as the power engineer arrived with his concept of how to power the satellite.  The power engineer envisioned a satellite surrounded by solar panels, and I still recall the thermal engineer’s initial reaction, namely “Don’t put me in a box!”  The four of us sat there in structure lead’s office and hashed out a top-level packaging scheme and I ran a quick calculation to see what that would weigh.  Just then Doctor E came in and looked at my figures with dismay.  He shooed us out and closed the door to the structures lead’s office.

The next morning the structures lead came to me and said he ran his own calculations overnight and agreed with what I’d come up with.  We marched into Doctor E’s office and presented a united front.  His reaction was “OK, but we have to keep the weight down to allow for specification creep.”  The three of us looked at each other and the structures lead had this look on his face that said “Duh!”

The next few weeks were hectic, 7 days/week for 10-11 hours a day as we breezed through refining the design, looking to minimize cabling, tubing, and electronics while I also spent a lot of time with component placement to keep the spin axis aligned with the deployment stage’s spin axis.  As time went on, my constantly updated mass properties database converged with my “back of the envelope” calculation to within a few pounds.  This was done by constantly questioning every part and any change the various groups decided belonged on the spacecraft.  With a cohesive group of dedicated engineers who shared a common purpose in winning this proposal, keeping the weight under control was relatively easy.  Finally, as the deadline for delivering the proposal neared, the company held a “Black Hat Review” of our proposal, meant to uncover weaknesses in our design and proposed methodologies.  This was held over a Saturday and Sunday, meaning most of the team finally got some time off while the upper management met with the “Black Hats” and walked through the proposal’s many pages.

Monday morning, as we came in, we heard that there would be an all hands meeting in the conference room.  A few minutes before the appointed time we filed in and were surprised to see the company President sitting up front next to the program manager.  Also present were other senior level executives.  Doctor E started speaking, telling us that the Black Hats, who were sitting in front of us, had never seen a stronger proposal.  There were a couple of nits, but these were truly insignificant items that were easily fixable.  We all started to smile, then the company President rose from his chair and walked to the podium.  He told us that the value of this particular project was small, and in a few months’ time the same government customer would be evaluating another proposal the company was working on.  The Program A proposal was worth more than ten times as much as Program B.  It was the consensus of the Black Hats that we would win the Program B proposal, at which point the government could (he said “possibly would”) award the other proposal to a different company, as we would already have won one.  Therefore, the Black Hats had decided to tell this customer that our company was a “No Bid” on Program B and this winning proposal team was hereby transferred to the Program A proposal.  You could see the disbelief on everyone’s face as we filed out of the room to pack up our belongings and head to the facility where Program A was already underway.

Arriving at the other facility, I went in and found my new supervisor.  I knew that there was already a mass properties engineer assigned to this proposal, which had been in conceptual design and pre-proposal activities for over a year.  I was told that the other engineer would temporarily report to me while the company found a place for him – in other words there was only budget for one mass properties engineer and I was to be it.  I didn’t like the feeling that I was taking someone else’s job away, but I went and found the outgoing engineer who had already heard what was happening.  He turned over his files to me, went through a quick overview of Program A, and left.

I went to my new desk, started going through the reams of paper and the mass properties database, and was shocked at what I found.  The program was seriously overweight.  There was a hard requirement for launch capability and the mass properties database showed our design was over by hundreds of pounds, fully 50% over the launch capability.  Obviously, we weren’t meeting requirements, with the trade-off being a severe shortage in range.  My first stop was with the flight design group to verify range versus payload and compare that to what the database said we were carrying.  Next, I went to my new supervisor and told him what I had found and questioned why he hadn’t told me about this when I had first met him.  Amazingly, he was unaware how severe the situation was, although he knew we were overweight.  I went to Doctor E, who was now the deputy program manager on Program A and explained what I’d found.  He said two words, “Fix it!”

Going back to my supervisor, I asked for a copy of the technical proposal.  He said it wasn’t finished, and I said then get me what we have.  I started going through the proposal subsystem by subsystem, checking what was in the proposal against the mass properties database, and verified that the database was generally accurate.  Moreover, it looked like the known unknowns were accounted for.  That, at least was good news – we weren’t worse off than I thought we were.  Next, I went to each lead, subsystem by subsystem, and introduced myself, explained that we had a severe technical challenge, and that I wanted to verify that what I had in my proposal document was the current design.  There were a few differences, but overall everything checked out.  Then I went to the vehicle architect and spent several hours with him and the systems lead going over what I knew, and with Doctor E’s admonishment behind me, explained that we had to “Fix it!”  Shaving a few pounds here and there was not going to give us a viable technical proposal – this needed a rethinking of what we were trying to achieve.

With the words, “If we remove an item, we achieve a 100% weight reduction of that item,” I shocked the system architect into action.  Together we called a mandatory meeting of all subsystem leads, where I repeated what I’d said and then went on to say that unless we could prove we needed an item, it was off the vehicle.  There was, of course, consternation.  We went single-string on many subsystems.  Structural pieces were pulled, the size of the whole vehicle shrank as space was no longer required for this or that box.  Cabling mass came way down.  We shaved material from component boxes, structural members, skins, insulation, combined functions of multiple electronic boxes into one component – anything to get the weight down.

I was on that proposal for six weeks without taking a day off, although I admit I did work half days on Sundays (five hours versus 10 or 11).  We passed our Black Hat Review.  We turned the proposal in but did not win the contract.  The customer said we were in technical compliance but that other companies had better cost and management proposals.  BUT – we did not lose on technical grounds, which we surely would have if we had been 50% overweight.  I can count that as a “win”.  Losing a proposal is not unusual, it happens a lot, just as a company’s decision to “No Bid” a proposal is not unusual.  These are part of corporate life, and corporate life lives on despite these setbacks.

The lesson learned is that a mass properties engineer is much more than a clerk.  Yes, we have to keep track of the mass properties, but that is only part of the job.  Know what your requirements are.  Keep your management informed.  Interact with your subsystem compatriots.  Don’t let a small problem become a big problem.  Look at the overall picture and determine if what you are doing supports that vision.  And most importantly – you may be the “Weights Person”, however, keeping mass properties under control is everyone’s responsibility, so enlist others in the quest to maintaining a technically sustainable design.

Robert Zimmerman

5 thoughts on “Success in Weight Control”

  1. Thank you, Robert, for the article providing insights into effective mass properties control. I cannot overstress many of the factors you’ve highlighted, but I would add getting management to also engage and holding everyone accountable for achieving the mass property and resulting vehicle performance objectives. The spring SAWE Journal (about to be released) will compliment this piece by exposing us to the myths of weight control.

  2. Great to see the SAWE is getting back to recognizing weight control after too much time has previously been spent on processes and procedures.

    1. Raymond,

      The topic for the Mass Properties Forum at the next International Conference (Norfolk, VA May 18-23, 2019) will be Weight Control.

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