Interesting, I never knew that the C5A was trialed for jumping. The C17 must have been designed specifically for that purpose as well as other purposes. Unlike the C130 which you actually had to jump out of like the old days, it used to amaze me that they could slow down a big jet like the C141 enough to jump. The deceleration was extreme, like the bird was just hanging in the air when we exited. Any faster and it would rip you apart when your chute deployed. In the bigger jets, it must be even more noticeable.