Unplanned Freefall? Some Survival Tips
greenharbor.com
greenharbor.com
This is of course being a little silly, but it does get the physics wrong. Your energy is proportional to the square of your speed, so you have 25x more energy to dissipate at 120 mph, not 5x. Even if your five point landing was perfect, each of the five 'hits' is the equivalent of a landing at just under 60 mph, not 24.
In the case of you landing, I don't think energy balance is the way to look at it; each of the collisions that slows you down will transfer some energy to the ground. In terms of force, the force is dependent only on the acceleration, so it comes down to how long each impact lasts. If each "bounce" or "thud" lasts the same amount of time (I don't know if this is realistic) then each one will transfer 1/5th of the force, as the article says.
Potential energy is linear with height. AKA it takes the same energy to climb from floor 1 to 2 as 2 to 3.
Gravity is 32 feet per second per second aka you gain speed over time. In a vacuum 0 to 32 feet per second takes 1 second, 32 to 64 feet per second takes 1 seconds, 64 to 96 takes 1 second etc.
However, in the first second you fall 16 feet. in the next second you fall 38 feet because you where falling at the start of that second. Thus, it takes more energy to increase your speed.
PS: What's confusing about rockets, is your fuel has momentum. So, when use it your consuming the energy it took to get that fuel up to speed with you. Further, at low speed most of the energy goes into the exhaust not the rocket.
Doesn't make sense. Care to explain? Are you saying it takes less energy to take an object from 0 to 10m/s than it requires to take it from 10m/s to 20m/s?
E = 1/2 m*v^2
dE = E1 - E0 = 1/2(10^2) - 1/2(0^2) = 50J
dE = E2 - E1 = 1/2(20^2) - 1/2(10^2) = 200 - 50 = 150J
v = sqrt(2*E) = sqrt(200) = 14.1m/s
You can find plenty of examples but that's about it. Ex: You hold a gun in your hand and shoot it, the gun kicks back because momentum is concerved. But, the bullet is a lot more dangerous than the gun because while it has the same momentum it's got a lot more energy. Now, it hits a bullet proof vest. The vest still hits the person wearing the vest but because it obsorbed the energy it feels like a strong punch instead of making a hole in them.
A second gust at 10 m/s is NOT enough to further accelerate the balloon to 20 m/s. Because the wind and the balloon are now travelling at the same speed. It follows intuitively that the second gust should contain more kinetic energy than the first gust.
Say m=2 so we're just left looking at the v^2 terms:
120^2 - 96^2 >? 24^2 - 0^2
5184 >? 576
So yes, the KE difference between 120 and 96 is greater than the difference between 24 and 0.
*KE == kinetic energy
kinetic energy: "energy of an object is the energy that it possesses due to its motion. It is defined as the work needed to accelerate a body of a given mass from rest to its stated velocity. Having gained this energy during its acceleration, the body maintains this kinetic energy unless its speed changes."
in normal person terms: the energy of moving, or ~exercise, in a parallel world :)
> “If you ever fall off the Sears Tower, just go real limp, because maybe you'll look like a dummy and people will try to catch you because, hey, free dummy.”
Stuart Smalley - Character played by Al Franken.
Jack Handey - Real person, writer on SNL, did Deep Thoughts voiceovers.
http://ufpnews.com/window-washer-survives-11-story-fall-onto...
Better yet, just put your hands in front of you and land on all ten fingers. Then it's only 12mph. /s
In reality your entire body is moving at 120mph, so you can't divide the forces in this manner. This a PSI problem. Total inertia distributed over a given area. And the results are much less favorable.
Also the author didn't mention my favorite survivor Juliane Koepcke. https://en.m.wikipedia.org/wiki/Juliane_Koepcke
I have a piece of avalanche survival kit made for skiers/snowboarders called the "AvaLung" in my off-piste bag. It draws air in from around the face, and vents your exhalations out behind you. People have survived being buried an hour or more wearing one of those.
Basically cross your arms, legs and look forward
When I was child I used have fun by climbing to the top of conifers behind our house to sit on the highest branch and just slide down
Each successive tiered limb would catch the bend on the ones above and I would slide down perfectly fine
Man, I wonder if we're going to end up seeing someone's free fall smartphone video someday. Not everyone is going to read this article and be prepared to survive like we now are, so what if they decide to use those couple of minutes falling to try to record a message to their loved ones? The audio would be blown out but I don't see why the camera wouldn't continue working. That would be quite disturbing to watch.
Undoubtedly, since it has with other kinds of video cameras: https://www.youtube.com/watch?v=hFSp-SRGhNs
"I'm dead. Bye." (He was not, amazingly.)
Multiple gopros record an in-air collision of skydiving planes: https://www.youtube.com/watch?v=7p6hqMnsLFY&list=FLR2K9vyQEB...
Tangled chute: https://www.youtube.com/watch?v=ciIjdvNo65s
I can't find it but I've seen two more videos of people who have survived near freefall after parachuting accidents. One became a paraplegic IIRC.
As someone who has actually done that, tumbling is really bad. The titanium artifacts in my foot and leg are a permanent reminder of it.
Stick to plain sliding and trust your leathers.
I needed a skin graft.
PS: That's waaay better than tumbling...
Also interesting that having a towel could be incredibly useful in this situation.
http://topgunbase.ws/i-flew-my-wingsuit-into-trees-and-woke-...
This reminds me of college, where sometimes the police would come looking for students who were foreign nationals, because they had gotten credit cards and then racked up huge balances buying stuff, but didn't bother paying the bill. When the creditors tried to have them served, it turned out they had already graduated and left the country. Good luck getting some guy in Indonesia to pay off his US credit card balance. What were these creditors thinking?
Actually if you have a credit card, you might have a travel insurance as well. So no need to ignore the bills. And in France it's not like in US where the first thing they ask you is the name of your insurance company, even if you're bleeding to death.
I was talking about a scenario where a tourist to the US goes to a US hospital and racks up a lot of medical bills.
As someone who participates in a reasonably-dangerous / reasonably-uncommon hobby, that discussion really resonates with me. So much in there to contemplate.
Thank you!
Graham Dickinson died in January.
There's a blog entry that addresses that aspect:
http://topgunbase.ws/experience_doesnt_mean_shit/
>> Inexperience kills our new pilots.
>> Complacency kills our high-time pilots.
If you're young, you have no dependents and you feel like life probably isn't worth living then go for it, otherwise better not to pretend that you are a bird, you aren't. Birds have lots of options, wingsuit flyers (all terminology and pretense to the contrary) are not flying as much as they are falling and gravity has no mercy.
There is a fairly good reason why proximity wingsuit flyers tend to have a limited life span.
Whether or not you wear a parachute is not very important once you impact a tree or a mountain at high speed.
Hence, all the information learned in this one will be useful at some point in this or another life.
Now I don't know what to do with this information .. I don't want to need it..
And then if fate really leads me to fall from a plane, I will definetely remember this article which will seem infinitely funnier in mid flight.
Heck if I don't hit the ground laughing my ass off !
Makes me wonder if annihilation is possible in the future life, but not this one.
I also find it interesting that all the information in our DNA and what our body does with it is a form of 'remembering' what has been transmitted from previous lives, right ? :)
What if, in a similar way, what we learn here is compressed and optimized for next lives - things that are called 'talents', 'instinctual knoweldge', 'natural gifts', etc.
There's also no guarantee that past or future lives happen in the same type of body (or same planet or even same Universe).
Maybe it's an Eagle next time, who knows ? ;)
> Heard about the guy who fell off a skyscraper? On his way down past each floor, he kept saying to reassure himself: So far so good... so far so good... so far so good. How you fall doesn't matter. It's how you land!
It sounds so nice in French.
Amazing film, by the way.
Spoiler warning: https://www.youtube.com/watch?v=P52eqNKCpYc
The article had several first-hand accounts of people who had fallen off cliffs, wagons, and the like, and one skydiver who survived impact by landing in a muddy ditch. The article was especially interesting since I was a skydiver at the time and all of us jumpers could relate to the feelings described. Not only that, but the one skydiver interviewed had jumped at our drop zone and was known by most of us.
Sadly, I can't remember where the article appeared. I think it was Smithsonian Magazine but I have been unable to locate a reference online. If anyone else locates it, please post.
LT;DR, people didn't actually experience time slowing, they just happened to remember more of what was happening.
Falling from a plane, you have a minute to land after waking up. You can move laterally 2 miles by controlling your body. That gives you 13 sq miles to land. In this order, aim for: snow, swamp, glass skylights, large bushy trees (but not redwoods.) Water is almost guaranteed death. Stay "flat" until right before impact, and move to a standing position. Relax and go completely limp. If you follow this advice your odds are good.
My more detailed comment, with sources/numbers, is here: https://news.ycombinator.com/item?id=13840660
Also, regarding water: while I've heard the standard comment that hitting water can be as bad as hitting concrete, that seems like it would apply more if you have a larger surface area. Divers can dive from 35+ meters, and hit at 60+ mph, without any injury at all. If you are capable of aiming and landing feet-first and remaining as streamlined as possible, would water still be a fatal option?
The problem is that you're hitting water at 120mph. A 60mph impact of a 50kg person is 35kJ; a 120mph impact of a 50kg person is 150kJ. That's 4.5 times the energy. I'd almost certainly choose water (with a streamlined, pencil dive profile) over concrete, but that doesn't mean it's not going to be far more fatal than any other options.
https://youtu.be/yGJqqDaKscQb - 'Mythbusters for the Impatient' video showing dropping a pig onto concrete vs water. The concrete drop actually decapitates the pig!
But let's say you are still strapped to your airplane seat, or you can grab hold of another large object and ride it. Are your chances of surviving better landing in water or on ground?
In all my years at school, university lectures, and work-related training workshops, that one day of skydiving class remains the only time in my life when I was 100% completely focussed, awake and attentive for every subject.
But if you do pass out, your muscles will be relaxed and offer more give in absorbing the force of your body. Ideally you'd land on your feet, let you entire leg basically collapse and break, bones flying everywhere, and maybe you'd have a chance to live. Land on your head, chest or any other area with vital organs...being unconscious will not do anything for you.
1) you'll knock out either because of lack of oxygen or because of a violent spin
2) you'll freeze to death
3) you won't be able to position yourself properly or fly in a particular direction because of lack of training, so you'll hit the ground at a random place so hard that you'll die.
What I would do is flip to my back not to shock myself with the view of the earth coming at 120mph, relax and wait.
Towel huh. The speed difference is so big, that you'll never see a towel, that happened to fall off the same airplane as you.
There was a case in Russia not so long ago when a cameraman, who happened to be a very experienced skydiver, fell off a helicopter. He managed to drive himself towards a pond but died immediately because of water impact. The hit was so hard that his jumping suit was almost stripped off his body.
A few improbable things would need to also hold: 1) Spike would need to stay straight as it entered the water. 2) Spike should not significantly increase terminal velocity, at least not for most of the descent
I think (?) it's doable, but would be fun to see the physics worked out. E.g., how long should the spike be? What should be its shape? How could it be kept maneuvered into the right orientation for entering the water without significantly increasing terminal velocity?
I wanted to add a game achievement for "30 seconds of free fall". Achievable on something like the Vomit Comet. Going for 5 minutes of free-fall would have required something like a rocket. Nobody liked either of my ideas :-)
You can control four variables: your speed, your landing position, your landing orientation, and your muscles.
- Increase your surface area as much as you can, that's your only way to slow down. Best case scenario you'll find a parachute, put it on, and slow down to 25mph or so; worst case, you'll manage to point yourself in a bullet shape and hit 200 mph. Realistically you'll go into a "flat" position and sail along around 120mph.
- Make yourself "flat" until you're about to land, then position yourself such that you land feet first.
- You can move, as the site said, about 2 miles horizontally falling from 15,000 feet: aim for trees, a heap of soil, or snow if possible. If you know the area, aim for any buildings with a large glass skylight - that's saved two known freefallers [0].
- Relax your muscles as much as you can. This can greatly improve your odds. By "greatly improve your odds" I am not kidding: this is almost definitely the single best thing you can do, and being fully relaxed can make you half as likely to die. [1]
There's also a very good possibility you're not at 35,000 feet. For example:
- You fall off the Burj Khalifa, 830 meters high. You'll fall for about 20 seconds, the last 5 or so near terminal velocity. Use your body to move and aim for the trees near the base of the tower - you've got enough time to make it, easily.
- You fall off a very tall building, ~500 meters or so. Same as the Burj Khalifa but you have less time, so think fast.
- You fall off a shorter building. There's no time to maneuver or slow down. With the few seconds you have, point your feet down and relax.
If you're over water, your odds are very low. The best option is to go in feet-first like a pencil dive.
Remember, you _do_ have an OK chance at survival. Between 5 and 15 people have survived free fall, most of which did not know what to do. From 15,000 feet up, you can land wherever you want inside a 13 square mile area - 2 miles in any direction. That's probably enough to get you to some trees at the very least. You can draw that on a map with this tool [2].
You can seriously improve your odds of survival by following these steps. Landing on snow, or a swamp, or a glass skylight makes your odds quite good. Landing in trees makes your odds OK. Making yourself flat gives you more time, and grabbing onto debris - if you can - can increase your chances of survival by 5 times [3]. Then, simply relaxing can double your chances of survival.
Finally, once you've hit the ground - regardless of what you did - there's a decent chance you're still alive, even if you'll die soon. Spend a short amount of time to stop external bleeding, keep your wounds clean and contact emergency services as soon as you can - ultimately, they will know far better than you what to do.
[0] https://en.wikipedia.org/wiki/Alan_Magee
[1] http://dx.doi.org/10.1016/j.alcohol.2012.08.006
[2] http://obeattie.github.io/gmaps-radius/
[3] http://www.popularmechanics.com/adventure/outdoors/a5045/434...
Unfortunately, this debris usually means you give up control, so it's a tradeoff you have to make. If you're over the middle of the ocean and two miles of lateral movement won't help you, by all means stay with your debris. But if you're falling over a mid-sized city, you have lots of things beneath you: buildings with glass skylights, piles of snow, and occasional trees. Landing on any of these things is far better than staying with whatever object you've got a hold of.
Although that's another interesting question. Maybe there's debris that wouldn't be particularly useful in slowing your descent, but could be useful to break your fall on impact... I can't immediately think of something that would be sufficiently good at that that it would be worth carrying with you though.
Unlikely to find one in a plane, though.
Inflatable life jackets too, but those probably wouldn't be substantial enough to make much difference. (Although probably better than nothing if you could manage to actually don and inflate one while falling.)
So the better that ratio the slower you fall. An airplane seat is heavy (lots of metal) but the surface area is about the same size as you.
The cushions could be useful if you can hold them in a way that adds surface area (i.e. not against you), but not the frame which is heavy and dense.
> Vulović continued working for Jat Airways at a desk job following a full recovery from her injuries.
So, basically your legs become a crumple zone.
I imagine it's by deflecting various parts of one's body, using them in a manner akin to flight control surfaces. But which ones? What's the short version for idiots?
As a student I've mistakenly jumped out of a plane quite far from the DZ and managed to track most of the way back during freefall (and flew the rest under canopy).
One more tip, always wear the largest rain coat you can find onto the plane and keep some nylon rope in one of the pockets so you could fashion a parachute on the way down :)
Has anyone actually survived an unplanned free fall like this?
The other common attitudes are head-down vertical, feet-first vertical, "sitting", and back-flying. The first three have a much faster fall-rate than belly-down, and are less stable. Backflying isn't quite such a difference in fall-rate, but is still harder to learn, and less stable.
How easy is it to learn? Well, unless you've skydived before, then you get around a minute to learn from scratch. Good luck to that!
because there aren't any around to blame it on you? :)
Most clothing fabrics are worse at stopping airflow than the tight nylon of a parachute, so the drag will be less than a chute of equal size. If you can somehow get it soaking wet it'll be more effective, as the fibers swell and make it less permeable to air; consequently, you might want to stick your shirt in your jeans before you piss yourself.
Even copy and pasting to a text editor yields pretty terrible results.
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Made it somewhat readable for me. Not a criticism but just in case someone has the same problem as me.