A couple of years ago, one of our equipment suppliers made the EXACT SAME mistake on a finite element stress analysis. It was for a part already in service, that had deflected (permanent deformation) about 0.25".
Well, they did a finite element stress analysis that showed tiny stresses and deflections (hundredths of an inch). They didn’t give enough information for me to check their work adequately, but this was clearly wrong. After going around in circles with them a few times, they finally figured out that the part had been dimensioned (in Germany) in millimeters, but the analyst (a consultant in the US) had assumed that it was dimensioned in inches. WTH, it’s only a factor of 25!
They always taught me to check units, too, and I’m religious about it, but I guess some people slept through that class.
(For you non-mechanical engineers out there, an FEA is a kind of computer analysis that estimates stresses in a loaded part.)
The Cat In The Hat