That is really a lot of fun. I once body air surfed from 14,000 to 5,000 feet before pulling the rip cord. It really focuses your mind to be falling/flying at about 140 mph!

ah, but momentum jumping is without a parachute from about 15,000 ft, the idea is that they move too fast to be spotted by the public. their reinforced bone structure means they can withstand the landing. well, the doc reckons that Jason can but Anubi doesn't think he should.

You may find the following true incident interesting: A skydiver (unreinforced) bailed out at about three miles altitude, and both main and reserve parachutes failed to open. The skydiver kept cool and oriented himself for minimum impact velocity and flat belly down arms under head impact orientation. He actually picked himself up and walked toward the ambulance! I used this incident in one of the ultra short stories accompanying one of my art pieces:
http://www.furaffinity.net/view/444535/

Ah, but they can pin drop, they could fall as fast as they want and not get injured