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Just in case you fall out of a plane without your 'chute

origin.popularmechanics.com

11–20 of 35 posts

Re: Just in case you fall out of a plane without your 'chute

#11

The mantra I've heard among BASE jumpers is "if the chute fails, go in head first" -- e.g., if the shit's going to go down, finish it quick instead of ending up a mangled vegetable.

If someone's hobby is throwing themselves off of high cliffs and buildings, I think that would prevent me from ever accepting their advice about anything.

Re: Just in case you fall out of a plane without your 'chute

#12

The mantra I've heard among BASE jumpers is "if the chute fails, go in head first" -- e.g., if the shit's going to go down, finish it quick instead of ending up a mangled vegetable.

If someone's hobby is throwing themselves off of high cliffs and buildings, I think that would prevent me from ever accepting their advice about anything.

Well, you could also look at it as taking advice from people with domain expertise in hard landings :)

Re: Just in case you fall out of a plane without your 'chute

#13

While very nicely written and a good read, I too was taken aback by "Lower body weight reduces terminal velocity" - Physics 101 anybody?

All objects have the same acceleration (g) but not the same gravitational force. Terminal velocity is reached when Fdrag = Fgravity. Remember F=ma, so Fgravity is (mass * gravitational acceleration).

Re: Just in case you fall out of a plane without your 'chute

#14

"To slow your descent, emulate a sky diver. Spread your arms and legs, present your chest to the ground, and arch your back and head upward." You will fall slightly (5MPH-ish) slower if you instead arch your back and arms in the opposite way, as if attempting to hug a large beachball. This position is slightly less stable though, so you risk flailing around and increasing your speed. What the article did not discuss…

I've read previously that you can move up to 12 miles in any direction while falling if you aim for it. Over most of America this gives you ample opportunity to find a tree. I've also read that you should come down in a sitting position on top of a tree. Haystacks seem like they would be too hard to spot until it's too late. A grain silo might be recognizable and have a thin enough roof to be helpful. I suppose you c…

12 miles in any direction from 22,000 feet (the moment you reach breathable air) seems unlikely to me.

That would imply 2.9 feet horizontal movement for every vertical foot.

Edit: typo in the calculation fixed. (29 => 2.9)

Re: Just in case you fall out of a plane without your 'chute

#15

While very nicely written and a good read, I too was taken aback by "Lower body weight reduces terminal velocity" - Physics 101 anybody?

Only in Physics 101 is the article incorrect. Outside of Physics 101, we stop assuming a vacuum.

Re: Just in case you fall out of a plane without your 'chute

#16

"To slow your descent, emulate a sky diver. Spread your arms and legs, present your chest to the ground, and arch your back and head upward." You will fall slightly (5MPH-ish) slower if you instead arch your back and arms in the opposite way, as if attempting to hug a large beachball. This position is slightly less stable though, so you risk flailing around and increasing your speed. What the article did not discuss…

I've read previously that you can move up to 12 miles in any direction while falling if you aim for it. Over most of America this gives you ample opportunity to find a tree. I've also read that you should come down in a sitting position on top of a tree. Haystacks seem like they would be too hard to spot until it's too late. A grain silo might be recognizable and have a thin enough roof to be helpful. I suppose you c…

> I've read previously that you can move up to 12 miles in any direction while falling if you aim for it.

Skydiver here. You could manage a mile or two; no more. But both this and changing your body position is quite a bit harder than you might think. You have to push against the air in quite a counter-intuitive manner. A beginner will just flail about and probably start spinning; especially without any tuition.

Re: Just in case you fall out of a plane without your 'chute

#17

Earlier quoted context omitted.

I've read previously that you can move up to 12 miles in any direction while falling if you aim for it. Over most of America this gives you ample opportunity to find a tree. I've also read that you should come down in a sitting position on top of a tree. Haystacks seem like they would be too hard to spot until it's too late. A grain silo might be recognizable and have a thin enough roof to be helpful. I suppose you c…

12 miles in any direction from 22,000 feet (the moment you reach breathable air) seems unlikely to me. That would imply 2.9 feet horizontal movement for every vertical foot. Edit: typo in the calculation fixed. (29 => 2.9)

I think your math is wrong...12 miles is 63,360 feet, or 2.88 horizontal feet for every vertical foot.

So yeah, it still seems impossible.

Re: Just in case you fall out of a plane without your 'chute

#18

While very nicely written and a good read, I too was taken aback by "Lower body weight reduces terminal velocity" - Physics 101 anybody?

Less mass means less force exhibited by the earth on the baby. This means less force the wind exhibits on the baby has to overcome to match the force of gravity on baby. It also means less impact force. Think dropping an ant from a plane. It's terminal velocity would prbably be very small, and the force it feels on landing likewise.

Re: Just in case you fall out of a plane without your 'chute

#19

Earlier quoted context omitted.

12 miles in any direction from 22,000 feet (the moment you reach breathable air) seems unlikely to me. That would imply 2.9 feet horizontal movement for every vertical foot. Edit: typo in the calculation fixed. (29 => 2.9)

I think your math is wrong...12 miles is 63,360 feet, or 2.88 horizontal feet for every vertical foot. So yeah, it still seems impossible.

Yeah it does. But I read it on the internet so it must be true.

Re: Just in case you fall out of a plane without your 'chute

#20
I've always wondered what I'd do. I imagined ripping off some clothes (pants in particular, if I still had them) and creating just enough of a "parachute" or flying squirrel effect that I'd be able to slow down to about 60mph and hit the ground at 45 degrees instead of 90 degrees.

Inspired by, e.g. http://news.nationalgeographic.com/news/bigphotos/21240738.h...

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