Been a few years sense I worked on a 727 and I can't remember without looking at one in the shop. What the sprag actaully holds I'm not sure, thanks for correcting me, but if the shaft is secured by the failing sprag then that makes my point in judging the speed of the front drum and how you can't specify. Sort-of like smacking a toy prop with your finger. It spins faster than the finger that hit it.