How to Fall 35,000 Feet And Survive (2010) | Hacker News Reader

How to Fall 35,000 Feet And Survive (2010)

popularmechanics.com

67 pointsTomte64 comments

Another good place to land is ant mounds, as in case of Joan Murray. "She approached the ground at 81 miles per hour (130 kilometers per hour), landing on a mound of fire ants. Doctors believe that the shock of being stung over 200 times by the ants released a surge of adrenaline which kept her heart beating" [1]

[1] https://en.wikipedia.org/wiki/Joan_Murray_%28skydiver%29

Jesus Christ. At that point surviving is the curse.

If there is any decent vertical feature, a good skydiver could try flying into it and sacrificing an arm. It probably wouldn't help but if we are talking optimal strategy here, that's probably near the top.

A friend of mine had his primary fail and he passed out. He woke up before the ground and fired his reserve. That broke his neck. He fell hard, there was no one in the area he fell in, but he was able to gather his chute and walk back to base with his chin on his chest without passing out. Though I think he crawled the last kilometer or so.

He started skydiving again, pretty much as soon as they took off the neck brace that had been screwed into his skull.

There's probably room here for a niche consumer product. Something that one could wear on a flight discretely, that would behave as a makeshift parachute should one find oneself in this circumstance. If it were cheap enough (and not ridiculously uncomfortable) I'd probably consider buying one.

Wearing one of those...the TSA may want a word with you.

Bringing a parachute on a airplane is fine. The problem is there is no good way to exit a modern airliner.

In a situation where you are free falling from 35,000 feet, the problem of exiting said modern airliner has already, apparently, been solved.

If your last name is Cooper you may not be allowed on the flight. No reason.

see https://en.wikipedia.org/wiki/D._B._Cooper to know why

I've taken a parachute as carry-on multiple times... only been a problem once.

A related niche thing I'd go for would be flight that when arriving at the destination city would drop to 10,000 feet, open a door and allow any passengers carrying parachutes to jump out before continuing to the airport. Much more entertaining than getting a cab.

You would need a parachute for a cabin bag and checkin luggage too in that case! :)

Sign me up. When I'm flying home I get very irritated passing over my house on the way to the airport, knowing that it will take me another couple of hours to get back to my house.

I used to get up before the sun, drive 30 miles to the regional airport, wait an hour to get on a plane to Chicago, fly there, wait an hour for another plane to San Jose, get on that and fly for half an hour and then...look down and see my house. THAT sucked.

There's a pretty narrow case where that would be useful. If the plane breaks apart at 500mph at cruising altitude you will most likely die immediately.

Absolutely. If a commercial plane is too damaged to make a reasonable emergency landing, you probably won't get to use your parachute.

The only case it would be useful if if there's nowhere in range to make a reasonable landing -- no airports, no water, no roadways, no flat land. Given that your fly thousands of feet above the ground, it's unlikely that would happen.

It's worth noting that "water" is the last thing in that list that you'd want to consider landing on.

I remember reading that one.

My feeling was that your best bet is to not have to try.

Take the easy way out why don't you! Meanwhile, I think it's more fun to contemplate the possibilities.

I'm thinking I'll build a multi-story, Tempur-Pedic mattress maybe on top of shallow lake. Put some nets around it that extend high into the sky. The person landing on it gets cushion from the water and compression along with soft surface. Will hit it, slow down, and any bouncing contained within nets. Just need some idi... brave adventurer to both fund this structure and use it.

Note: Too great a chance of bouncing outside the nets. A spring or rocket activated top could help but hurts as much as the ground. Make hamburger out of them probably. So, a parallel, Tempur-Pedic surface that springs across the top or is moved into place with helicopters. That should be safer for high-energy, upward bouncing.

Yeah, about that... None of what you said would work. People think water is this "cushion" like thing. In reality it is as solid as a brick unless the surface is broken (the mattress is not enough). A human would just end up breaking every bone in their body attempting to do this.

I've dove in water enough to know this is true. Couldn't recall mechanics of breaking surface properly, though outside basic dives. Modification: something between the mattress and water to break the surface. Maybe repeating structures that do that in a single layer. What now?

Indeed. The practical design is probably something more like a large air bag as used in ski jumping http://www.magicfr.com/wp-content/uploads/2014/09/babsnowboa...

Yeah, I'm thinking along those lines. I had the thing in mind I see in movies rescuing jumpers and a BouncyCastle. It works for small distances. How to get it to work for larger distances and with potentially other materials?

I imagine the big airbag/bouncy castle thing would work for free fallers. You'd need it to be quite thick like 50ft and quite large so you don't miss it jumping out of the plane. From mountaineering I think polyester tends to have the best strength to price ratio. There's a supplier here that can make 800 tons / month at about $2000/ton. Say 1 kg/m2 and .5 km x .5 km = 250 tons = $500k. Plus airpumps etc. Kickstarter?

Polyester seems interesting for it. A Kickstarter would be funny on this. I'm still at early exploration phase. Holding off.

"HITTING THE OCEAN IS ESSENTIALLY THE SAME AS COLLIDING WITH A SIDEWALK" -from the article

Which is specifically why I put a cushion above water with potential mechanisms for breaking it.

Perhaps an air filled cushion is better than a mattress. Once the subject hits the cushion, it deflates. That would absorb much of the impact and prevent bouncing.

If a large article of debris hit prior and you entered the churning, bubbling water(and not hit the debris), you may get off with just broken toes, feet, hips...maybe. Of course, you'd likely drown before you could swim back to the surface.

Chris MaClugage jumped a ski over three houseboats in Havasu a few years back. They aerated his landing area to buffer the landing/impact. Seems to have worked...

https://www.google.com/url?q=https://www.youtube.com/watch%3...

Mythbusters tested this: https://en.wikipedia.org/wiki/MythBusters_%282003_season%29#...

You still die:

Dropping Buster with an internal accelerometer from a crane led to difficulty because the dummy continually lost parts on each control impact. Eventually, they managed consistent drops (mostly just below 300 g), finding that the hammer reduced the impact slightly, but the 150-foot (46 m) fall would still be lethal.

Did they test proper landings or drop it randomly? That's a critical thing left out of many analysis. You learn its importance to preventing injury in both martial arts (esp relaxing or break falls) and military, jump school. The methods for high falls should be tested on each of those techniques given prior effectiveness.

It seems they tested whether a hammer could break the surface enough. Larger debris would create a significantly larger disturbance and would probably be more effective.

Doctors recommend not getting cancer.

One of my favorite resources in the how-to-survive-a-fall-from-a-plane genre is wikiHow's "How to Cope With a Double Parachute Failure: 10 Steps." [0] My favorite paragraph is the last step in the second scenario "Alternative: Lack of Companions".

> 5 Expect impact. You are unlikely to have the time or ability to aim for a soft landing-spot, body of water, or other impact site that might improve your chances of survival. There is a minuscule chance that your impact will result in non-life-threatening injuries; if this seems incredibly far-fetched, comfort yourself that double chute failure in modern times is also extremely unlikely, and that you have already beaten worse odds.

[0] http://www.wikihow.com/Cope-With-a-Double-Parachute-Failure

EDIT: readability, grammar

I remember this article. It was really fun. Now, anyone know of modern research or simulations that has made some headway on how these people might have survived? And best odds of duplicating that should one find themselves 10,000+ft in air with no parachute? Or just idiotic basejumpers trying to create a new category in Guiness?

MythBusters did some research on The New Jersey airman mentioned. In general you need something that will slow you down in a relatively gradual way over 20 feet + or so. Things that have worked are deep sloping snow, branches of large trees and in the Jersey case the roof of the train station which seems to have been made of a metal lattice that presumably bent some distance when he hit it http://fly.historicwings.com/wp-content/uploads/2013/01/High...

Nice, nice. That's a start. I also recall in the original Final Fantasy movie that they landed by shooting gel packs that did exactly that. It spread out and up a certain distance. Then, they hit it with immediate slowdown. I wonder if that was forward thinking or leveraging something someone already heard about.

I'd worry about suffocating in the gel solution. If it's thick enough, you'd probably get stuck. So, something with give like other examples is better.

I find it hard to visualise the gel pack thing.

I was thinking just now of Mike Basich kind of demonstrating the landing in snow bit. He aimed to jump out of a helicopter on a snowboard at 50ft for a magazine photoshoot but it ended up being nearer 130ft. I think that makes it about a 60mph fall so not terminal velocity but pretty quick.

Vid of jump https://youtu.be/OC42K5ex0iA?t=18s

Him talking about it from 22m30 https://vimeo.com/7732513

Would being drunk help? In drunk driving crashes the drunk driver survives more often than the others directly involved in the collision, but I've never gotten a definitive reason why...

EDIT: survive more often than others directly involved in the collision who were in a comparable vehicle or in the same vehicle as the driver.

s/accident/crash/g

Sorry, fixed.

I believe the reason is related to the safety of the driver's position in the vehicle rather than the state of being drunk. The driver's seat is the only one guaranteed to be filled each time the car is driven, therefore car companies have a bigger incentive to care about the safety of that seat than any other seat.

People also steer themselves away so the collision is more likely to happen on the other side of the car.

Physics? I would assume the car driven by the drunk driver is travelling at a faster speed than the car hit.

They're relaxed. Tensing up in a crash means muscles don't absorb impact, they transfer it to bones and organs. A relaxed person has a better chance on a fall or crash... up to a point, of course.

The brother of a dad's friend survived a 5000m jump in the 60s. He was doing an airborne jump in the mont blanc area, both parachutes failed (super rare), and he freefalled into a tree. He basically broke most of his bones and spent 2 months at the hospital but made it!

Whoever wrote this obviously has never seen a skydiver impact the ground at high speed. Watch a video of high performance canopy pilot, or "swooper", impact the ground at 60mph; they bounce off the ground like rag dolls, and are usually left with broken femurs. An impact at 100mph will most certainly kill you unless something extraordinary breaks your fall.

- crispytx (Wingsuit Pilot & Programmer)

Whoever wrote that isn't concerned about the people in almost certainly crowd. Writer is curious about the others that made it anyway and why. Much more interesting question with possible, practical applications. :)

True. But over open water? It might be worth taking a stab at it, though you're probably going to die anyway from falling debris, drowning, hypothermia, sharks, or just bleeding out.

Open water is as hard as concrete when impacted at high speed. It doesn't compress and doesn't "have time" to move away.

Can confirm. When I was younger I did this and got very hurt.

another case like that https://en.wikipedia.org/wiki/Vesna_Vulović

"Lower body weight reduces terminal velocity,"

How does this work?

Air resistance affects lighter stuff more, proportionally, and gives it a lower terminal velocity. A mouse can be dropped and survive (maybe with broken limbs) from almost any height, as there's not a lot of mass behind it and the air will keep it from going too fast.

This is in contrast to the Galilean experiment where you drop two things and they fall at the same rate regardless of mass - this is true in a vacuum but not in atmosphere.

"Air resistance affects lighter stuff more"

This is nonsense. Air resistance is caused by drag and has nothing to do with weight. An arrow will fall faster to the ground than big balloon, despite weighing the same.

It's awkwardly phrased, but it's pretty clear what they intended from the rest of the comment.

"This is nonsense. Air resistance is caused by drag and has nothing to do with weight. An arrow will fall faster to the ground than big balloon, despite weighing the same."

But if you had two arrows of different weights, air resistance would act to slow the lighter one more.

So no, it's not nonsense.

Like a ping-pong ball vs a golf ball. The gravitational force is smaller on a light object, so less drag is required to counter it. Being the same shape, that drag is reached at a lower speed than for the heavy object.

Gravitational force is proportional to mass; in a vacuum, the only thing that stops heavier things from falling faster is the fact that acceleration due to applied force is inversely proportional to mass, so the mass cancels out.

Drag is proportional to cross-sectional area and the square of the velocity; mass doesn't factor in.

There are two main forces on the falling object, then: gravity pulling it down, and drag pushing it up. Terminal velocity is reached when both are equal. Lower mass means less gravity, but drag is unaffected. Thus it takes a lower amount of speed increase until drag equals the gravitational pull, and terminal velocity is reached.

Thus, take a compressed-air tank with you. Point it down and open the valve to increase the air density that you are falling through. Is this so complicated???

That basically amounts to a jetpack, and yes it would help!

Yes. Assuming a relatively consistent body density, mass will be proportional to the cube of the linear dimension (say height of person falling) and cross-sectional area will be proportional to the square of the linear dimension. This is why an ant can make it to the ground without a parachute.

    F_drag = K_1 * velocity^2 * Size^2
    F_gravity = K_2 * Size^3

Acceleration will be zero when the forces balance so terminal velocity is:

    v_term = sqrt((K_2 * Size^3)/(K_1 * Size^2)) = K*sqrt(Size)

So if an ant is say 10mm long and a human is 2m long (200 * the length of the ant) the human falls 14 times faster.

Furthermore, the forces on our bones at impact will be likely be proportional to the cube of our size while their strength will be proportional to their cross section, related to the square of our size. This give the ant a big advantage at impact as well.

Finally, I would probably die of fright on the way down, the ant wouldn't know any better.

It is not solely about weight. It is the ratio between weight and surface area. Surface area tends to go as the square of the size whereas mass tends to go as the cube. For objects of the same density (all people are about the same), smaller and thus lighter ones have a greater surface area to mass ratio, and thus a lower terminal velocity.

This is also why, e.g., ants basically never die when you drop them. Also helps cats.

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