Unplanned Freefall? Some Survival Tips (2001)
greenharbor.com
greenharbor.com
Stephen passed away January 2021 from COVID (but had an amazing 85-year life) and I was just reading his diary from the incident. The gist:
There was still an hour left before an emergency landing at SFO. The cabin was festering with vomit and tears, but there was a profound sense of love and connectedness and compassion among every passenger. Every one felt touched by a Divine Grace.
However, after a only few hours at the terminal and people could finally leave, it was every person for themselves as they physically and verbally harassed each over to get to where they were going. So quickly back to being selfish humans...
My Mom said she would drive from Los Angeles to get him, but he said that if he didn't get on a plane right then, he would never be able to fly again. So he courageously flew SFO->LAX right away, one of many flights he would continue to take throughout his life.
* (obvi unfortunate that it happened and people had to experience that)
and sorry to hear about your father.
I end up just jumping from one article to another through the "see also" links and similar accidents
Edit: occasionally you'd also find a podcast episode covering a particular crash or documentaries like air crash investigation or similar
https://www.old.reddit.com/r/AdmiralCloudberg/
It's obviously not extremely technical (though a lot more than I'd have thought), and it's probably nothing you can't get from more in depth websites but it's neatly organized, well written and the articles are getting better and better. I like that he keeps conjecture to a minimum too but still points out what lessons can be learnt from the tragedies.
The only thing is that I'd recommend reading it through the Medium link he posts in the comments instead of the linked imgur albums. It's a much better experience
Edit: here's a wiki link:https://en.m.wikipedia.org/wiki/List_of_Mayday_episodes
Eg last month "Screwdriver tip left in engine during maintenance results in engine failure on take-off"
What does "corrected tens of seconds before impact" mean here? Thanks.
What to do if you find yourself falling from a great height: consider how lucky you are that life has been kind to you so far. If life hasn't been kind to you so far, which is not unlikely given your current circumstances, consider how lucky you are that it won't be bothering you much longer.
And since this is not a naturally tenable position for a whale, this poor innocent creature had very little time to come to terms with its identity as a whale before it then had to come to terms with not being a whale any more.
This is a complete record of its thoughts from the moment it began its life till the moment it ended it.
Ah … ! What’s happening? it thought.
Er, excuse me, who am I?
Hello?
Why am I here? What’s my purpose in life?
What do I mean by who am I?
Calm down, get a grip now … oh! this is an interesting sensation, what is it? It’s a sort of … yawning, tingling sensation in my … my … well I suppose I’d better start finding names for things if I want to make any headway in what for the sake of what I shall call an argument I shall call the world, so let’s call it my stomach.
Good. Ooooh, it’s getting quite strong. And hey, what’s about this whistling roaring sound going past what I’m suddenly going to call my head? Perhaps I can call that … wind! Is that a good name? It’ll do … perhaps I can find a better name for it later when I’ve found out what it’s for. It must be something very important because there certainly seems to be a hell of a lot of it. Hey! What’s this thing? This … let’s call it a tail – yeah, tail. Hey! I can can really thrash it about pretty good can’t I? Wow! Wow! That feels great! Doesn’t seem to achieve very much but I’ll probably find out what it’s for later on. Now – have I built up any coherent picture of things yet?
No.
Never mind, hey, this is really exciting, so much to find out about, so much to look forward to, I’m quite dizzy with anticipation …
Or is it the wind?
There really is a lot of that now isn’t it?
And wow! Hey! What’s this thing suddenly coming towards me very fast? Very very fast. So big and flat and round, it needs a big wide sounding name like … ow … ound … round … ground! That’s it! That’s a good name – ground!
I wonder if it will be friends with me?
And the rest, after a sudden wet thud, was silence.
Curiously enough, the only thing that went through the mind of the bowl of petunias as it fell was Oh no, not again. Many people have speculated that if we knew exactly why the bowl of petunias had thought that we would know a lot more about the nature of the universe than we do now.”
― Douglas Adams, The Hitchhiker's Guide to the Galaxy
If you want to learn how to do any of these things, go to your local wind tunnel and practice. Without that practice, you should just enjoy the minute or so of spectacular views before you go splat.
Also, even with that experience, you'll probably go splat. Best case your aorta will disconnect and you'll bleed out after a few seconds. This is common even when people are stopped by the harness (e.g. by hitting trees). Human body just wasn't designed to accelerate (decelerate) that quickly.
This is what I've always said. The only time I'll skydive is if I already find myself falling out of a plane. Then I'll cross it off my bucket list as I go splat.
"Awesome or hilarious poses to choose from on your decent towards massive and permanent deceleration".
Given that you woke up after falling 20,000 feet, anything that in itself is “aerodynamically suitable” will be high above you by now (1) or, if it dropped of before you started falling, be miles behind you. Even that tightly packed parachute likely has lower terminal velocity, and will be out of reach by now.
I guess your best (not one with good odds, but still best) bet is an airplane door with an uninflated glide that you can tie yourself to, remove from the door, and then inflate.
(1) you can see that with rain showers: it’s the smaller droplets that hit the ground last
Note: This is a nice experiment for ~12 year old students that are learning to measure things in the laboratory. Just get two sheets of paper and make a ball with one of them, and measure the time when they fall from a fixed height.
The time of the ball of paper will have a nice distribution. You can probably measure the time 5 times and have a good idea of the average and dispersion. Moreover, most of the dispersion in the time is due to the problems to start and stop the stopwatch, and perhaps some problems to release the ball.
The flat sheet will dance randomly while falling, and the time will be very inconsistent. I don't remember the details, but you should repeat the experiment like 20 times to get an idea of the distribution. The average changes, but the dispersion is a lot higher an impossible to avoid.
[1] I'm not sure which is the correct word in English.
About the correct word: I have no idea what the best word is, but the way you wrote it certainly brought images to my mind of various ways I've seen falling debris act. I honestly wonder if using the "best word" would have been less useful to my comprehension - but I'm in general a big fan of the word1/word2/.../wordN way of describing multi-faceted/ambiguous/complex statements.
"Flutter", perhaps?
would fall like an autumn leaf
And to think my friends and I used to jump off a 2nd story balcony for shits and giggles. Even after one of us broke an arm doing it. Just 2/3 of the way towards certain death!
If you’re going X speed after 2 stories, you’d be going sqrt(3/2)X = 1.22X after the last 1/3rd, ignoring drag.
Energy increases linearly with fall height though, and energy is probably what mostly kills you. (Again ignoring drag.)
Sadly this is not how it works. Kinetic energy is proportional to the square of velocity, and so if you can equally split the impact energy 5 ways, it's as though each impact is at 54mph. A bit harder to absorb.
If you manage to land on a nice slope, catching the transition will vastly reduced the peak force. The angle and composition of the slope will determine your outcome. Soft spring snow is probably best. Powder snow would have a much lower impact force, but most like you'll become deeply embedded and suffocate. Grass, shrubs or loose soil would be the next choice. If it's rocky or trees terrain you're probably toast
Also, no matter the landing zone, it seems like you should try to minimize your landing speed by maximizing drag until the last moment, then switch to a position from which to execute a five-point-landing (or going through the water surface with feet first) - I'd be interested in strategies for how to successfully execute that.
Mythbusters did it, it didn't help.
It is not from the 0.07275 joules per square metre of surface tension.
But if you found a waterfall, you might try to land in the area that’s bubbling up. That could conceivably improve your chances when hitting water, which are very slim - hitting water in free fall is not that much better than hitting concrete.
Trying to execute a stand-up 2 or 3 seconds before impact might help you survive, I could buy that. I’d guess this is something that’s difficult to do without having tried it before, it usually takes a few tries to do without flopping back to flat.
Terminal in stand-up is indeed much higher than terminal in the flat position. A perfect stand-up / head-down is around 180mph typically, while flat is around 120mph, give or take depending on body shape & density. But it takes time to accelerate, long enough that I think if you stood up quickly you’d still be around the flat-position velocity. The maximum you can theoretically accelerate is about 22 mph/s, but you’re starting from terminal with tons of drag, so I think it would take 5-10 seconds to reach 180mph, and you can go from flat to stand-up in 1-2 seconds.
Now obviously the shaft here functioned nearly like a gun barrel so the manhole cover could've reached 5-6x the escape velocity (according to the scientists), but even just being accelerated to 10% of escape velocity in the span of milliseconds would've turned the hapless Mr. Jones into a fine red paste. Assuming he resided in a metal fridge at the time, he would've become what can only be described as a flat tin can of pâté.
Edit: And before anyone mentions the fact that Brownlee's calculation did not take into consideration atmospheric forces (which probably disintegrated the cap before it got to space), at least some molecules of the cap probably did go that far, and would still remain the fastest, and possibly furthest object from Earth (assuming it did not get caught in the gravity well of another object on its way out).
There have been objects placed even closer to nukes that have survived and note Project Orion--not only objects near a bomb, but the plan was to put a crew near bombs. Obviously, they would catch some radiation but that's going to happen anyway in deep space flight and back then they didn't realize the cancer risk.
The basic physics of protecting the ship and crew from the nearby detonations is clear. There is some question about whether it could actually be used to take off from Earth, though--it's not so certain if the pusher plate could be kept cool enough during the ride to orbit. Deep space doesn't require such sustained thrust, it's no problem. EMP from near-Earth detonations is a big issue, though.
> Let's say your jet blows apart at 35,000 feet. You exit the aircraft, and you begin to descend independently.
As far as I know, most airplanes don't do that nowadays. They tend to descend more or less in one piece (or several big pieces) to ground level and "blow apart" there. If they do blow apart at high altitude, it's probably due to an explosion which is apt to drastically reduce the chances of passengers being conscious (or alive) during the free-fall phase.
Not mentioned is the fact that at 35k feet, the average temp is around -40 to -55 degrees Celsius. I don’t know if it would kill you, but you’d probably freeze some skin, and if you try to look you might freeze your eyeballs. It will be hard to move muscles after sixty seconds of 120mph freezing wind.
I’m curious if the passing out part is true. It certainly might be. My experience skydiving is that I would get light headed and seeing stars at 18k feet unpressurized, and the instant I jumped out of the plane, everything got better. Seemed like the force of the air in my face somehow packed all the oxygen I needed. 35k is very different from 18k, obviously.
* Oh yeah, and speaking from experience, I know it’s hard to see straight without wearing goggles when in free fall. I forgot to put them on once before jumping. Never forgot again after that.
If you haven't seen it, watch it from beginning.
You have 30-60 seconds at 35k. At 18k you'll feel it but you'll be down long before it's serious. (Although if it was unpressurized for the climb I wonder how much of the time you used up that way.)
Real world data--a guy punched at such altitudes and lost his oxygen in the process. Blacked out, came to on the way down. Amazing survival--he was supersonic at the time and punched without blowing the canopy.
Pretty interesting. I wouldn't have imagined you could do this.
Don't leave home without it.
This is only possible because it's behaving like a wing and generating lift if you look at the shape closely... probably out of luck to find a piece of debris that is going to behave like an airfoil well enough, but this parachute user can land with zero injuries, if you only want to survive, perhaps some concessions can be made, and this made me wonder:
If you found such a flat and light enough piece of material with a useful surface area - how best to use it? even if it's not the right shape to generate significant lift, there are different ways to use it, and one of them causes the smallest terminal velocity - the obvious use is directly against the airflow like a flat parachute - but would it work better if you tried to convert your downward force into a horizontal one by deflecting the air into one direction? (like a really bad glider, or those wingman suits). My instinct says yes, but without lift I can't explain why, I suppose because I can see where the force is going (horizontal) rather than just "dissipating" through turbulence.
I suppose at the minimum, by directing the flow to one side you provide yourself with significantly more horizontal mobility for choice of landing site.
https://www.guinnessworldrecords.com/world-records/88729-sma...
https://www.nytimes.com/2021/06/18/science/koepcke-diller-pa...
I've often thought about this topic since the explosive decompression of Malaysia flight 17 over Ukraine. The anti-aircraft missile apparently caused an instant, explosive decompression of the plane. Assuming you weren't hit by one of the projectiles, you would have found yourself suddenly free-falling.
There is one case of a guy who apparently hit a pine tree perfectly, then a snow bank *and walked away*, with no injuries that were obviously from the landing. No aiming or anything, pure luck. (The injury situation is uncertain because he was injured when he jumped and hadn't had time to take stock of his injuries.)
Fun fact, Vesna [0] from Serbia came down in Srbská (Serbian) Kamenice a small village in Czechoslowakia. What a coincidence. Btw. there was an article about this incident just this year [1] with some pictures.
[0] https://en.wikipedia.org/wiki/Vesna_Vulovi%C4%87
[1] https://zpravy.aktualne.cz/pred-49-lety-roky-teroristicky-ut...
As long as holding onto it doesn't result in you orienting your body away from presenting the most area to the oncoming air. Don't hold onto a beach ball for example.
Juliane Koepcke, one of the only people to survive such a fall, did it strapped into a row of seats. And when she landed she was in good enough shape to survive 11 days in the Amazon rainforest (!!!) and make her own way to safety. So I'd say statistically, it's about the best thing you can do.
“If thus connected, you have some questions to address. Is your new conveyance air-worthy? […] If you choose to go it alone”
Also, even if it is dropping faster, it may be worth it to stay in your seat if you can use it as a crumple zone
Which isn't to say you won't feel your seatbelt tugging on you. You will likely be straining painfully against it. But that's because you'll be tumbling wildly, the entire assembly battered and buffeted by huge forces.
Weight/mass doesn't matter, as all objects of the same shape above a certain density fall with the same speed. So literally just pick the widest object you can find, no matter how heavy it is, and ride it.
Terminal velocity occurs when the drag force balances the gravitational force. So F_d = F_g
F_d is proportional to the area of the object and the velocity squared.
F_g is proportional to the mass.
So, for constant area, at terminal velocity we have v^2 ~ m or v ~ m^(1/2) where "~" denotes a proportional relation.
Thus a heavier object falls at a higher terminal velocity than a lighter one.
I can't help but feeling panic and hopeless if I were in that situation because THERE'S NO UNDO BUTTON / CANT SAVE-AND-RELOAD, you have to do it right at first attempt! Can slide to forest? Whoops I just missed it.
I'm not sure if their analysis is accurate, but it's sure fun to watch :)
Deep Thoughts by Jack Handey