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Skydive into a hole

Air cushion to reduce velocity
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I've heard it proposed for space vehicle reentry, but why not apply it to sky divers. All you have to do is aim for a hole in the ground that is small enough and deep enough to provide an air cushioning effect that slows you down. I hope you are an accurate diver...it'd suck to miss.

[Edit] Yes, this is based on creating a loose seal. I've never actually gone sky diving, but I'd imagine that you would have to be an expert. It may be possible to shape the hole into a sort of funnel where non-centered approaches receive some air pressure from close walls in order to stabilize and center the falling body. [/Edit]

This was inspired by the skydive without a chute entry.

toodles, Aug 07 2009

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       How accurate would you have to be?   

       I assume you are implying that you would make a loose seel around the edges of the hole creating a pressure differential which reduces you velocity.
miasere, Aug 07 2009
  

       //How accurate would you have to be? //   

       Fifty points for a bullseye. Zero for everything else.
ldischler, Aug 07 2009
  

       That'll make your eardrums ache. :)   

       You might want an outflow of air from the hole. (However, you'd not want it to start before your entry.)
lurch, Aug 07 2009
  

       There are no problems with this apart from some.   

       The main one is that, normally, you would open your chute at 2000ft, and spend the first 8-10,000ft doing stuff.   

       If you adopted the same approach for hole-diving (*do not google that*), you would use only the last 2000ft of freefall to aim for the hole. I don't reckon you could track more than a very few hundred feet horizontally in 2000ft of freefall, which means that the spotter would have to put you out of the plane pretty accurately. In reality, spotters tend to put you out wherever they feel like it, as long as they can see the drop-zone, or recognize a field in the same county as the drop-zone, or are at least not offshore.   

       Therefore, we'd need new technology. The hole-divers would need to be mounted under the wings on special racks, and dropped by a military-trained bomber using a laser sight more or less directly over the hole.   

       Incidentally, I may consider founding the Barnes-Wallace Offshore Skydiving Society, if I can refine the release mechanism and find some sufficiently robust zorbs.
MaxwellBuchanan, Aug 07 2009
  

       I think if there were not an air outflow from the hole you might stop too abruptly. If the hole were rigged as a tube, the outflow air might be used to power a noise maker or possibly suspend a small child in midair.
bungston, Aug 07 2009
  

       So this does not stop you, only slow you down. There would have to be a big mattress, or a pile of feathers, at the bottom of the hole. And then, there you are, alive, sitting on a pile of feathers at the bottom of a very deep hole. How do you get out before the next skydiver comes hurtling down towards you?
pocmloc, Aug 07 2009
  

       // How do you get out //   

       You pay the two bucks .....   

       // at least not offshore //   

       That depends rather more on the pilot than the spotter.   

       // mounted under the wings on special racks //   

       Why not some type of cluster munitions dispenser ?   

       Glider pilots favour the updraft caused by power station cooling towers; and the shape is such towers is suggestive. Perhaps power station cooling towers could be employed, equipped with suitable blowers arranged around their base ? The pool of rusty, malodorous, lukewarm water in the centre would be a most attractive landing spot......
8th of 7, Aug 07 2009
  

       I was going to post an idea along these lines;   

       Make a structure 15'x15' wide by 50' high out of inflatable supports and plastic sheeting with an open roof, but a sealed floor. Set it up in an open field, filling the bottom 15' with water. On top of the water put 5' of alcohol. On top of that, put 30' of xenon. Then drop the skydiver into it with only a 3' drough chute and air mask. They will fall from the plane at ~100mph, then slow dramatically upon hitting the much denser xenon, then the alcohol will ease them into the water, which will slow them all the way to zero.
DIYMatt, Aug 08 2009
  

       How do you stop the alcohol and water mixing ? There will be considerable mixing at the boundary unless you segregate them with a membrane.   

       Xenon is a highly mobile, noble gas. Normal convection will cause it to rapidly disperse.   

       You could, of course, use Radon .....
8th of 7, Aug 08 2009
  

       //How do you stop the alcohol and water mixing ? //   

       Drink the alcohol first, then jump.
ldischler, Aug 08 2009
  

       //membrane// So it's a single use device, no problem.
pocmloc, Aug 08 2009
  

       Feed the alcohol to the seal. That should make him nice and loose.
BunsenHoneydew, Aug 10 2009
  
      
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