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What is the best strategy to survive a free fall naked out of a jetliner at cruising altitude (ignoring temperature)?

For instance, my strategy would be to streamline my fall so that my terminal velocity was very high. Then at some critical distance above the ground I would pitch upward and attempt to use my forward velocity to achieve lift. Presumably this would slow my fall to some survivable speed. (This is roughly what the space shuttle does after all.)

Would it work? And idea if it would be survivable?

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Only if you had wings. –  Anixx Mar 20 '13 at 0:21
    
"survive a free fall naked out of a jetliner at cruising altitude" without a parachute or at least a gigantic cushion conveniently placed on the ground it's not happening –  Michael Brown Mar 20 '13 at 0:23
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Don't try this at home kids. –  Michael Brown Mar 20 '13 at 0:25
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PS: You achieve terminal velocity after approximately 450 meters of free fall. Anything above that doesn't make any difference whatsoever, so it doesn't matter whether it's 450 meters or cruising altitude. –  Lagerbaer Mar 20 '13 at 0:44
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@Lagerbaer In each of those cases the person either a) died soon thereafter of irreperable injuries or b) had something to arrest their fall. For example, the hostess who was still in part of the airplane when it crashed, or the passenger who was strapped to her seat. One of the airmen fell through pine trees, another slid down a snow bank, and the stuntman had a partially deployed parachute and a wingsuit. The conditions of the OPs question, as I read them, were that you are outside of an aircraft with no arresting gear and you can't count on a soft landing site. –  Michael Brown Mar 20 '13 at 0:58
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1 Answer

up vote 4 down vote accepted

I would guess you've heard that an airplane in a spin or some other critical state can dive to build up speed, then when it pulls out of the dive the increased speed increases the lift and can allow the pilot to regain control. You are presumably asking if the same idea can be used for a falling person.

The problem is that an aircraft wing is carefully designed to use forward velocity to achieve lift while a human body has no surfaces that can be used in this manner. The airflow around a falling person will simply be turbulent and will cause drag but no lift. Skydivers can control their flight to some degree but this is mainly by moving the drag with respect to their centre of mass, and while this can effectively rotate them it provides little or no lift in the aeronautical sense.

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plus an aircraft has propulsive energy available, which the naked human body does not have ( if you discount exhaling from available orifices :) ). –  anna v Mar 20 '13 at 9:11
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:-) though diving to get out of a stall works for gliders as well. –  John Rennie Mar 20 '13 at 9:12
    
@John: You're right, but it's not so much about gaining speed as about reducing the angle of attack. –  Mike Dunlavey Mar 20 '13 at 15:37
    
This seems like a reasonable answer. Thanks! –  John Berryman Mar 21 '13 at 1:17
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