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There's many recorded instances of stuff like this happening (mostly during WW2 since that was the last time we had large numbers of people falling out of planes). If you hit things that let you decelerate over enough distance to not go splat then you can survive. IIRC one guy landed in water at terminal velocity and only broke his ankles because he landed feet first instead of belly flopping. Obviously there is some luck involved.
I remember reading about someone jumping from a big height and purposefully going in feet first to break his legs and not his back, but I've always wondered how deep you would actually go if you hit the water hard enough to break your ankles.

I mean, it's already a slightly terrifying experience to jump from a tall trampoline and go a few meters deep, if you're not used to it.

Not that deep, water is massively higher density than air (imagine the Column of air above you when you stand outside that goes up for miles and miles, you only need to go 10m under water to equal that weight, i.e. 10m ~ 1atm).

There is footage of people firing guns into water and you can see the bullets deceleration.

>There is footage of people firing guns into water and you can see the bullets deceleration.

Mythbusters did an episode on this one. Bullets shot out of high-powered rifles simply shatter on contact with the water, turning into a bunch of shrapnel.

https://www.youtube.com/watch?v=yvSTuLIjRm8

This is also why you should not try and land in water at terminal velocity.
Darn it, I guess I'll have to change my plans for Sunday if that's the case....
So let's say I'm falling at terminal velocity and I'm falling to a point roughly at the shore of a deep body of water. I have just enough control to deviate so I'm landing completely on (hard, dry) land, or completely in water that is over 20 feet deep.

You're saying I shouldn't try to land in the water?

(Let's assume there is no beach of sand. This is at a dam or something)

If those are your options, then you should go head first into the dam. You're not going to survive, so you want to die quickly, not suffering in pain for a few minutes.
Mythbusters also did an episode where they compared dropping (dead) pigs onto concrete and dropping pigs on to water, from a height where they reached terminal velocity comparable to a humans. Both pigs were Very Dead. IIRC, the pig dropped into water was slightly less Very Dead, but it was still Very Dead. They weren't actively guiding themselves to land feet first but I wouldn't expect much out of that.

Water could be a component of a survival plan (e.g., "my partially deployed parachute is slowing me down enough to make this the equivalent of a high dive"), but "just land in water" is not a survival plan on its on from terminal velocity.

How you land in the water is key. In the Navy they teach us to point our toes, cross our arms, and basically make ourselves hit as little of the surface as possible when jumping from the top of a tall ship.
Related, I wonder how high the risk of drowning is in a situation like that. I expect I would impulsively gasp from the shock/pain and inhale a lot of water.
We had a nearby case where two special forces dudes drowned in parachute training exercise because due to wind changes they landed on a major river. Water landing is not safe even if you're an experienced skydiver, you may have to swim quite far to get to the shore while not really prepared for long-distance swimming, with all your clothing, boots, parachute and all that.
I feel like landing in water could be just as dangerous, because if you do survive the fall, you then have to make sure you don't drown.
Interestingly, this is NOT the first time tings like this happened. There are a few people that survived freefall from absurd heights [1]

My favorite website that documents all these things is the Free Fall Research Page [2] that to my dismay now seems to be on the bottom of the second google search results page.

Most people have this image about falls that you fall from heights you die, but some people are lucky and it really depends on how and where you fall. I was with some friends once and was mentioning about all these people that survived free fall and I was surprised to get some really incredulous looks of the type "Sure they did buddy, do you believe everything you read?" even tough these cases are well documented. I think it just goes to show that if something is deemed impossible in popular culture it might as well not happen at all, ever.

[1] https://en.wikipedia.org/wiki/Category:Fall_survivors

[2] http://www.greenharbor.com/fffolder/ffresearch.html

And of course the manual on how do it: http://www.greenharbor.com/fffolder/carkeet.html
Well, I would have thought there'd at least be a TL;DR - time is of the time is of the essence when you need to consult that.
Ideally you look this up before getting started. But I feel like I am just missing a joke you are making :p
It’s actually pretty interesting, but to your point, apparently children can tolerate a higher fall.

Here’s a reddit post where a kid falls from a window and a lady is trying to help her back home:

https://www.reddit.com/r/WTF/comments/c0j87k/kid_falls_from_...

It’s largely due to their lower mass and flexibility. It’s all about deceleration. Depending how they (and adults) fall how their chances of survival are impacted.

Air resistance goes by surface area, weight goes by volume. Terminal velocity depends on ratio of those two. And thats what matters on long falls.

The rule of thumb I heard is that a hamster survives, human dies and an elephant goes splat.

The orignal quote is quite poetic:

> "You can drop a mouse down a thousand-yard mine shaft and, on arriving at the bottom, it gets a slight shock and walks away. A rat is killed, a man is broken, a horse splashes." - J.B.S. Haldane

Thanks! I knew it sounded familiar. replacing elephant with horse does paint a ... Better?.. picture in my mind.
a hamster on a road will most likely die, a human with a wingsuit has good chances to survive
I know this lunatic who is into base jumping. And according to him, if the body isn't in the right position within a few seconds of jumping you are dead. Dumbest sport on the planet.
> lunatic

> Dumbest

Stay classy.

"Able-ist" language is the crime that has gone on here.

Only learned of the ableist word recently and my spell checker has problems with it.

Calling someone who regularly risks their own life for no benefit other than thrill a lunatic is hardly “ableist”. It’s accurate.
Base jumping isn't just wingsuits although it's pretty dangerous in any case. From what I can see, at least the more extreme wingsuit jumpers (is there another kind?) pretty much all die jumping sooner or later.
Not sure if you're interested, but the risk of base jumping comes from the fact that you're starting from zero airspeed, which means that all of your "flight control surfaces" (arms, legs, torso, etc.) that skydivers use to re-position themselves during falling are useless. There's not enough air flowing across your limbs to produce any usable force.

This means that there's a risk you're not in the necessary deploy position when the critical throw/survive moment arrives, and you carry an increase risk of not surviving.

I don't know about dumbest sport, but it's definitely dangerous. Also, not all BASE jumps are the same. The problem comes when people keep looking for that next thrill. I at least partly understand. I've sky dived before, and jumping out of an airplane is exhilarating like few things I've personally experienced.

With that said, the person who I first sky dived with is dead now. She misjudged the wind on a BASE jump and was blown back into the cliff.

The article is somewhat scarce on details but it sounds like both of her pilot chutes opened while failing to deploy main/reserve chutes. Pilot chutes alone will push your terminal velocity way down. If she fell in wooded area those chutes were likely to catch on branches which again would have been hugely helpful in slowing her down. I find that [1] Vesna Vulović case is a lot more curious in terms of miraculous survival.

[1] https://en.wikipedia.org/wiki/Vesna_Vulovi%C4%87

Having a read of the wikipedia it says she was discovered screaming amongst the wreckage so maybe was attached to some part of that that descended slower than human free fall speed?
This one goes into a bit more detail regarding how she managed to survive the fall:

https://allthatsinteresting.com/vesna-vulovic

"While many other passengers were sucked out of the plane after the explosion, Vulović became pinned by the cart. The small section she was in fell to the ground on a heavily wooded, snow-covered hillside.

Vulović’s doctors concurred with the air investigators and added their own conclusions. They claimed that the very thing that almost kept Vulović from being a flight attendant is what ultimately saved her life. Her physicians believe her low blood pressure kept her heart from bursting on impact with the mountainside. "

It's not much of a miracle. The official version of the event is probably false. The aircraft was likely shot down by czechoslovak forces at a low altitude in a monumental fuckup.
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Shower thought: after some inflection point, does your likelihood of survival actually increase with altitude? With the additional height you gain additional time to plan and travel to fall more optimally, while your acceleration should fall to nearly zero.

Of course, there may well be a secondary ceiling (pun) where air pressure and O2 create new complications...

> after some inflection point, does your likelihood of survival actually increase with altitude?

For humans, no. After ~10sec you’re falling at terminal velocity, which is generally 2-300km/h, and your odds of survival are extraordinarily close to zero.

This lady had a double malfunction, where there were issues with both main and reserve parachutes, but per a police report (1), she was descending at 60km/h, so she must have had at least some parachute material out and slowing her fall.

She’s very lucky, despite what’s likely to be a shitty next couple of years of rehab, but this isn’t a “fell from an airplane without a parachute and survived” miracle.

(1) https://www.lenouvelliste.ca/actualites/une-parachutiste-gra...

I wonder if psychologically this ended up being a good thing. As in, physically the rehab might be bad but mentally.. it's bound to put things into perspective.
"For humans, no. After ~10sec you’re falling at terminal velocity" That means that falling higher will not increase your already slim chances of survival, and might well increase them, if ever so slightly. No?
Hard to say definitively - double malfunctions are relatively rare, so the sample size isn’t enormous.

More time can increase the likelihood that you can get some piece of parachute fabric above your head. And if you can do that, the odds go way up. There’s a saying I was taught on the first jump: “keep fighting until your goggles fill with blood.”

But if you cannot get a parachute out for some reason, a longer freefall will only give you more time to contemplate your fate.

Right so 300kmph = 83.3 m/s which means every 83.3 metres (call it 100) buys you an additional second of thinking time and back of the envelope calculation (2km/minute) [0] suggests you can move up to 33 metres per second horizontally (feel like this is optimistic - I openly welcome corrections here...)

In any case a fun thought experiment

[0]https://www.quora.com/What-is-the-average-horizontal-distanc...

There’s a joke in skydiving: “What happens if your backup parachute fails? You aim for the car of the person who packed it”
It took a long time for aircraft pilots to discover that height is actually good with airplanes. After a few seconds, you are at terminal velocity. This ends up being only a few hundred meters. After that, you have a few thousand meters before the air gets too thin to breathe. So, the higher up you went, the more time you would have to react to issues that arise.

Largely, you can measure the height of the airplane in mistakes.

It takes time to fix a mistake. You have to first realise you are in a mistake, then you have to take in information, then you have to decide what to do, then you have to do it (the OODA loop). Since you reach terminal velocity rather quickly, it's all about the time you have left before you reach the ground and die.

So in airplanes, the higher you are, paradoxically, the safer you are.