There is a glitch with the jetpack where you take fall damage after turning off jetpack from a fall of less than half an inch. i have had it take 15 damage, i wasnt moving fast or anything, just hovering and turned off my jetpack and fell for fall damage form almost no drop with no momentum. This has happened to me a lot. NEEDS FIXING

The jet pack 'fall damage' occurs when jumping and then activating the jet pack. If after doing this you jet pack to a position lower than you were you will encounter the apropriate amount of fall damage when you deactivate. You can't activate the jet pack whilst you are falling so the only way this can happen is if you jump and then activate the jetpack.

ahh thats what causes it, cool least i can avoid it now, although still needs fixing though imo.

or else bring back the parachute!

Or, land in the sea. No fall damage there.