a wrote:
I read or perhaps misread that rescue chutes might bring you to the
ground at about 25 feet per second. This is about as fast as you'd be
falling from a bit less than a 10 foot free fall under 1 G. I
remember an old physics axiom that states if you were in free fall
under 1 G for 10 feet, and you stopped in 1 foot, you'd experience an
average of 10 Gs.

Your recollection of the physics is correct. The basic equation for uniform
accelerations (no drag, no initial vertical speed) is:

a*Sa = g*Sg

where "a" is the deceleration rate, "Sa" is the deceleration distance, "g"
is the acceleration of gravity, and "Sg" is the distance the object fell
during free fall.

Derivation is left as an exercise for the student. :-)

10 Gs in a sitting position is pretty much in the
tolerance range of most of us. Ejection seats in fighters provide
about 15 Gs over more than several feet.

As to what gee forces are survivable, Wikipedia appears to have a
surprisingly decent article on the subject:

http://en.wikipedia.org/wiki/G-force