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I worked at Boeing on a large satellite program back in this same time frame (2008-2011). I worked on the software simulator for the satellite that was used to test flight code and the ground system (i.e., give the ground control software simulated satellites to talk to, and to ring out procedures).

Anyway, as the final configuration for this satellite was still being tweaked, I needed to get updated mass properties (in order to simulate the physics properly) from the team working on the real satellite as the configuration changed (e.g., they added more batteries, solar panels, decreased RCS tank size, etc.). Ordinarily, these would be emailed to me in an excel spreadsheet every so often. I would make the updates, life would go on.

Now, internally, the simulator software worked with metric units, and the spreadsheet I received would also use metric units. Apparently, one day an engineering manager on the vehicle team found out that one of their engineers had been "helping" the simulator team by plugging the mass properties into an excel spreadsheet, translating the units from imperial to metric, and sending them to me (I did not know any of this, of course... I just knew the vehicle team would send me updated mass properties from time to time).

This was an outrageous affront to said manager, who ordered his folks to not expend any time helping "some other team." So, the next time I needed updated mass properties, what did I get? A faxed copy of something that looked like it had been generated on an old line printer. I called and asked "Where is the spreadsheet?" and got "Sorry, that's all I can do anymore."

Some of the numbers were questionably legible, but I tried to use it anyway. As I was making my updates, I noticed the numbers were way off. Units weren't labeled on the fuzzy faxed copy, so it took me a few minutes to realize that the vehicle engineering team apparently worked with imperial units internally.

Angry phone calls back and forth ensued, but I don't recall the (political) issue ever being fixed. I didn't stay much longer, so I don't know if it was ever resolved.

I’m surprised there wasn’t a push to standardize units after this incident: https://en.wikipedia.org/wiki/Mars_Climate_Orbiter

I'm all for Freedom Units... But honestly if you're doing aerospace you just use metric and that's all there is to it! Period.

This is true for almost all engineering. I use metric but it is annoying in PCB design because mils is the standard there and those are just Tiny Freedom Units.

I'd be in favor of switching to metric for USA, but I see no indication of that happening. But a company has a choice esp one the size of Boeing!

The aerospace industry is stuck on imperial fasteners. That trickles down to other design elements.

That isn't the greatest example of that IMO. From what I've read, the real problem there wasn't just imperial/metric confusion, it was the fact that the team providing data did not provide any units at all, and the team receiving the data didn't ask and just assumed units.

One of the first things I was taught in engineering school was to always provide units! It doesn't matter if you're only using metric; that still doesn't tell you if it's a gram or a kilogram, after all.

I dislike using MCO as an example of why engineers should standardize units/use metric. This was one of the first NASA projects to be done using metric units with this exact goal in mind. The more interesting part about MCO is that it's actually a pretty compelling story about engineering culture interacting with management and how risks and problems are handled. It's not as simple as "NASA messed up metric" at all and people could learn a lot by reading the whole story.

Is there a tl;dr on those relevant parts?

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