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Monkeyb

Wuffo question: water impact

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This is a completely fictitious newbie question, but I'm curious.

Say you're at 5k and you have a double mal, both chutes fail and you're about to turn in. Would aiming for water be a wise decision? I believe that the speed + water impact would result in instant fatality, but then again you see great cliffdivers out there who also jump from high ass ledges and make it through unscathed.

Is there any way you can survive during a teminal velocity impact with water, or is it just as bad as hitting land?

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This is a completely fictitious newbie question, but I'm curious.

Say you're at 5k and you have a double mal, both chutes fail and you're about to turn in. Would aiming for water be a wise decision? I believe that the speed + water impact would result in instant fatality



yes to the instant fatality. if you have a double mal, aim for your rigger or his car:P

peace
lew
http://www.exitshot.com

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meh... i dunno. but if i had a birdman suit, i'd try to aim for water... i know you can slow down alot in one of those, i've seen people in those powerboat things hit the water at 100s of miles per hour and survive.. its possible.



Yea, that would deffinately make sense with a birdman suit. If you can slow down to a decent speed I'm sure a water collision would be survivable, and I hear good wingsuit flyers can flare down to like 60 MPH, which I would think is slow enough to survive impact since it's just water.

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So how do the cliffdivers survive? They jump from pretty high places. Obviously there's a difference in hitting the water with your belly and chest as opposed to a perfect vertical dive.

My brain tells me it makes sense, but everyone else says no.

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Yea, that would deffinately make sense with a birdman suit. If you can slow down to a decent speed I'm sure a water collision would be survivable, and I hear good wingsuit flyers can flare down to like 60 MPH, which I would think is slow enough to survive impact since it's just water.



Good wingsuit pilots can flare even slower than 60 MPH vertically but you still have a forward or horizontal speed component that would increase with the decrease in your vertical speed as your glide flattens out.

Unless you manage to skip across the surface like debris you would end up under the water in a suit that you, injured or not, cannot swim in and takes two people to pull you to the surface since it fills with about 30 gallons of water. The manual says stay away from water at any speed in the suit.

Aim for a billboard so you have something nice to look at for a few seconds. Or the resturant....... maybe they will name a burrito after you.

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First of all, cliffdivers don't get anywhere near terminal. At least I don't think so. Yeah, they're going fast, but they also know how to hit the water. You have to cut through it -- minimize surface area hitting the water, create some turbulent area where the rest of your body can go through. If you hit in a belly to earth position it'll be like concrete. Think about how much a belly flop hurts off a diving board, and that's like 15 feet at the most that you're falling. (I'm thinking platform diving here). The basic issue one of fluid dynamics. If you hit big heavy waves its gonna hurt and damage you less than if you hit flat still water, because the still water has all that surface tension directly opposed to the direction you're coming in at.

I'd say don't get in that situation in the first place. Pull at the right altitude, know your emergency procedures, and never give up even if you do have a double mal. I know i'd be climbing my risers trying to get my reserve to open...
Human beings, who are almost unique in having the ability to learn from the experience of others, are also remarkable for their apparent disinclination to do so. --Douglas Adams

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Water has /zero/ compressibility. To put it another way, the steam catapults on an aircraft carrier generate tremendous amounts of force.. Once the plane has been released, that catapult's shuttle needs to stop as quickly as possible. The Navy uses a very simply braking system. At the end of the shuttles track is a tube filled with water. The shuttle hits that and stops instantly.

-Blind
"If you end up in an alligator's jaws, naked, you probably did something to deserve it."

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Hi Monkeyb

Terminal velocity into water no way.:S

I wouldn't recommend doing a accuracy jump over water and trying to cut away to hit the target. Depth perceprtion over water is hard to judge and jumpers in the past have died trying this manuever. so we're talking maybe 50-100ft max and they didn't survive the landing.:(

R.I.P.

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he'd die. rather then wasting time trying to aim for water if you get a double mal, try pulling the pin yourself, or hook knife the side of the container open to get some nylon out. people have survived going in under a ball of nylon.

MB 3528, RB 1182

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A cliff diver doing a 5sec delay starts accelerating from 0km/h. If you want to hit the water vertical you start accelerating from de-arch velocity from an altitude from which you think is the last moment to get yourself vertical. If you survive you will never have to buy another beer in your live. Just make sure you have it on video!!!
There is a lot of stuff worth doing but then there is a lot of stuff worth doing instead.

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5 second delay, this is 366ft (111m) with a freefall speed of approx 84mph - do divers really do this sort of thing? b'jeayzus - if so thats a pretty hardcore sport!

anyone got information on this?? i dont know shit about it!! :)
cheers

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hitting the water above 35 mph is the same as hitting concrete like everyone else says. I saw a movie once where a guy shot a 9mm into a 5 gal bucket of water, the bucket survived but the bullet came out flat...



Hmm.. surely it's not exactly the same as hitting concrete, is it ?
I mean.. if you hit concrete you'll literaly bounce.
A body would not bounce off water from a vertical impact at terminal.. or would it ?
The water does yield to some extent at least, albeit not enough to make the impact survivable.

As for movies, as 'educational' as they are, in 'Saving Private Ryan' we all saw German MG bullets penetrate easily through 6ft of surf and 1ft of soldier before hitting beach sand, apparently not significantly affected by the water impact.

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...end up under the water in a suit that you, injured or not, cannot swim in and takes two people to pull you to the surface since it fills with about 30 gallons of water.



I've had two water landings in a suit (SF1, which is fairly restrictive). On the first I only had to swim for a few minutes, but on the second it was more than 10 minutes before the boat pulled me out. While swimming in the suit is difficult, it is not impossible. The suit takes on very little water, actually, because once you cut the wings away, they tend to collapse.

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The manual says stay away from water at any speed in the suit.



Definitely a good idea. Swimming in the suit is a pain.
-- Tom Aiello

[email protected]
SnakeRiverBASE.com

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I've impacted water at a touch over five seconds with very little out. I know of two people who have died at the same spot impacting with nothing out. I also know of two people (other than myself) who have survived very high speed impacts there.

I think a lot depends on how you hit the water. If you hit it flat, you're pretty much toast. If you can hit feet first in a good "entry" position, you can probably get away with a life flight trip and a hospital stay.

I'm not sure how this bears on impact at terminal, which I suspect would reduce the survivability to near zero.
-- Tom Aiello

[email protected]
SnakeRiverBASE.com

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5 second delay, this is 366ft (111m) with a freefall speed of approx 84mph - do divers really do this sort of thing? b'jeayzus - if so thats a pretty hardcore sport!

anyone got information on this?? i dont know shit about it!! :)
cheers



No, divers do not do this sort of thing.
Diving from 366 feet would be fatal.

High Diving consists of acrobatic dives between 23 - 28 meters, from 75-90 feet up, many times into very shallow water of around 9 feet deep. When the diver takes off from a natural rock rather than a man-made platform, it is reffered to as Cliff Diving. From that height, the athlete has around 3 seconds before impacting on the surface of the water. The speed when entering the water is between 78 km/h and 100 km/h.
__

My mighty steed

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ok even if you could survive a plunge into water at 120 mph...

a. you better hit the pond, lake, ocean etc. at a spot where it is fairly deep. otherwise you will hit the bottom hard, causing even more injuries.

b. you better have someone within 50 feet of where you land, because you are gonna be badly injured, and probably unable to swim. you will drown in a matter of minutes.


can anybody find anything on the web about the highest someone has fallen into water from? something tells me its not over about 300 ft.

MB 3528, RB 1182

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Actually, aim for a field with bails of hay. I understand they disperse quicker than water will. I heard a story somewhere about a British pilot bailing out and landing in a bail of hay and surviving. I don't know if there was any truth to that story.
Also don't forget to PLF. Anything is survivable with a properly performed DYNAMIC PLF. :-)

Chris

Chris
--------
"Life's journey is not to arrive at the grave safely in a well preserved body; but rather to skid in sideways, totally worn out, shouting 'Holy s#$* what a ride!'"

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This is a quote from an article on jumpers at the Golden Gate Bridge:

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In the four-second fall from the bridge, survivors say, time does seem to slow. On her way down in 1979, Ann McGuire said to herself, “I must be about to hit,” three times. But the impact is not clean: the coroner’s usual verdict, suicide caused by “multiple blunt-force injuries,” euphemizes the devastation. Many people don’t look down first, and so those who jump from the north end of the bridge hit the land instead of the water they saw farther out. Jumpers who hit the water do so at about seventy-five miles an hour and with a force of fifteen thousand pounds per square inch. Eighty-five per cent of them suffer broken ribs, which rip inward and tear through the spleen, the lungs, and the heart. Vertebrae snap, and the liver often ruptures. “It’s as if someone took an eggbeater to the organs of the body and ground everything up,” Ron Wilton, a Coast Guard officer, once observed.



If it's 1500lb/inch at 75 mph I'd hate to think what impact you suffer at 120 mph.

Water is just as lethal as concrete. Due to the laws of physics, (I forget the technical terms) if you try to move through a liquid quick enough it takes on the properties of a solid. Water can litterally act like concrete.

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Water has /zero/ compressibility. To put it another way, the steam catapults on an aircraft carrier generate tremendous amounts of force.. Once the plane has been released, that catapult's shuttle needs to stop as quickly as possible. The Navy uses a very simply braking system. At the end of the shuttles track is a tube filled with water. The shuttle hits that and stops instantly.

-Blind

Even an incompressible fluid can move out of the way if it has a route.

The issue is momentum transfer. Hitting the water requires a transfer of momentum to the water, and force = rate of change of momentum.
...

The only sure way to survive a canopy collision is not to have one.

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If you hit big heavy waves its gonna hurt and damage you less than if you hit flat still water, because the still water has all that surface tension directly opposed to the direction you're coming in at.

...



Surface tension forces are negligible in this context.
...

The only sure way to survive a canopy collision is not to have one.

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