>When I was living in San Diego, a parachutist jumped out of a plane and,
>whoops, neither chute opened. She hit a local lake and lived (though she
>was covered with muck from the lake bottom!). Or that's the story, anyway.
Well, that is not exactly the same. First, a parachutist's movement is more or less vertical and the body axis is parallel to the direction of the movement - so she most likely entered the water her feet first (less resistance) and then as her body get submerged the gradually increased resistance reduced her velocity. The same principle can be observed at the so-called escape ramps for runaway trucks in mountainous areas.
Second, a free falling human body does reach the speed of an aircraft (which is about 180-200 mph) because the forces of gravity is counterbalance by the resistance of the medium (air).
So the free-falling parachutist's behavior was more or less similar to that of a cat falling from the roof. As she realized that her chutes did not open - she probably turned around and spread out her limbs to get maximum resistance from the air which reduced her velocity. Then, just above the surface of the lake, she probably straightened her legs and arms to offer the least resistance to the medium she was about to enter. Planes generally can not do such maneuvers.
wojtek