I was once chatting to a friend who flew many years ago in the RAF.
He was remembering the time that G-suits first came out. He and a chum, knowing that these were precision pieces of equipment decided to help the equipment stores sergeant by being very well prepared.
They therefore spent some time measuring each other and themselves in as many places and in as many ways as they could think of.
Eventually they headed off to the equipment stores and when the sergeant asked them what size they were, proudly produced 2 lists of closely written figures listing every possible measurement.
The sergeant studied the lists inscrutably for a few minutes before sighing deeply and asking: "small, medium or large!".
I also worked for the RAF for a while, and took my RAF driving test. This (at the time) only differed slightly from the standard civillian driving test, in that it included a colour-blindness test. The reason for this was so that, should you ever be driving on an airfield in poor visibility, you could tell whether an aircraft was heading towards you or away from you.
It was only several years later that anyone told me which coloured light went on which wing.....