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Skydiving from 25 Miles Up
chisox writes "The Observer has a story about a retired French army colonel who is soon to make a free fall parachute jump from 25 miles up. In the process he will break the sound barrier, reaching a top speed of mach 1.68 before he opens his parachute 1,000 metres above the Earth. Of course, if the chute doesn't open, the hole he'll make will be about 1,000 metres deep." Well, actually his max speed will be high up and near the earth the atmosphere will have slowed him down to terminal velocity.
Will he really experience a sonic boom? If so wouldn't that destroy his ear drums.
Sounds very interesting. I wish him the best of luck in getting this done. I think I read something about him a couple of years ago, though I could be wrong.
I have to admit, considering applications of this, such as parachuting from a Space Shuttle, IIS, etc, it does make you wonder why something like this has not been undertaken by any government agency.
RonB
It is human nature to take shortcuts in thinking.
Wouldn't the amount of force be more than a parachute is used to receiving? This could possible rip a rope or the parachute itself.
Sponsored by the Darwin Awards...
What's in a Sig?
Well, actually his max speed will be high up and near the earth the atmosphere will have slowed him down to terminal velocity.
Well, actually he'll be at terminal velocity for nearly the entire time... Terminal velocity is dependant on the density of the atmosphere. You'd think that someone that posted a link to a page which defined "terminal velopcity" would have at least read the definition...
Wired had an article in August 2001 about two other people attempting much the same thing.
Someone should tip off the drilling companies: rather than pay skilled people to operate fancy drilling rigs, just drop the rigs and/or people out of an airplane.
If the cute doesn't open, the crater he makes will be the same size if jumps from 25 miles or 10,000 feet. That's how terminal velocity works. Sure he'll break Mach 1 in the thin air aloft, but as he gets to into progressivly thicker air he'll be slowed to the same 55 m/s as any other skydiver. As long as he doesn't tuck into a ball or go head first, that is.
... this kindof reminds me of the time that guy strapped a solid fuel booster to his Nova trying to break a landspeed record somewhere out in the desert. he hit a solid rock wall probably mere seconds after realizing no less than three critical errors in his planning:
1) solid fuel boosters can't be stopped; once they're ignited they burn till they're used up.
2) at 400 miles per hour those cliffs way off on the horizon approach much faster than you'd have thought.
3) it doesn't really matter how hard you push in on the brake pedal if the car is being propelled by something they use for jet-assisted takeoff of military cargo planes.
Its a plot, the French have decided to take back Canada by dropping old people on them... Oh well at least he won't hit nothin' too important when he crashes into Saskatoon.
only infrmatn esentil to understandn mst b tranmitd
Quoth the article,
The free fall will involve 200 scientific experiments in the stratosphere and the troposphere, some of them linked to the possibility of parachute escapes from stranded space shuttles.
ISTR that the speed of sound changes with air pressure and it's faster when the pressure is lower. The speed of sound at sea level is around 300 m/sec so mach 1.68 at sea level would be around 500 m/sec.
But at 100,000 feet, the speed of sound in that thin air might be 1000 m/sec. So if the guy is falling at 500 m/sec at that altitude, that's really just half the speed of sound there. If he's falling at 1700 m/sec, that sounds awful, sonic booms and all that kind of thing.
So what's the deal?
(* Of course, if the chute doesn't open, the hole he'll make will be about 1,000 metres deep." *)
I hope he does it near my hometown. I always wanted to visit that crater in Arizona, but it is too far and too hot.
We need a local one.
Table-ized A.I.
http://www2.tsixroads.com/Corinth_MLSANDY/jk004
including an amazing shot of him taken from the gondola from which he jumped:
http://www2.tsixroads.com/Corinth_MLSANDY/corin
I use Friend/Foe + mod-point modifiers as a karma/reputation system.
Speed of sound is significantly lower higher in the atmosphere, and since there is less air resistance, he can fall faster.
The last attempt, five miles lower, got pretty close to the speed of sound, this should do it. Not sure how safe it would be, but he should break it.
Of course, if his chute doesn't open, he becomes his own airbrake and bursts into flames.
I am a science fantasy fan
Nobody is obligated to do with their money what YOU feel is the best thing. How many of the qualities of life you take for granted today would not exist if someone hadn't "wasted" a lot of time, money, and effort on things that have "no relevance"?
I personally have no desire to float 25 miles up into the atmosphere in temperatures over a hundred degrees below freezing just so I can fall faster than the speed of sound. But if this guy wants to do it, more power to him. As long as SOMEONE is reaching higher for what nobody in their right mind would ever want to do, the rest of the world will benefit as a result, even if indirectly.
I'm not saying that funding medical research is bad. Its just as noble an endevour as any other. But to say that other reasearch does no good for the world simply because the immediate results do not, is very short sighted and reeks very badly of the "everything's already been invented" mentality. And besides, consider the fact that since he has partially funded this effort of his, the experiments he's carrying out will benefit agencies that otherwise would have to spend their own money to carry out similar experiments anyway. That means that money will be saved.. which means it might be available elsewhere, including your own personal preferred pet projects. And that's just looking at things from an immediate economic point of view.
-Restil
Play with my webcams and lights here
65 million years ago, the dinosaurs disappeared mysteriously from the earth, supposedly caused by an impact from a meteor or piece of comet.
A.D.2002: A retired French army colonel makes his skydive from 25 miles up. As he approaches mach 1.68, a bright flash is seen, and he vanishes. For years, the mystery of what happened to him remains unsolved.
A.D.2042: It is discovered that at the moment the retired colonel reached mach 1.68, he caused a rift in the space-time continuum and travelled 65 million years back in time and slammed into the earth at 1200MPH, creator a crator and wiping out dinosaur life.
According to the Worst-Case Scenario Survival Handbook (http://www.worstcasescenarios.com) if you plan to jump from anything high you should be prepared to at least break your legs, and clench your buttocks as you go down so as to keep water from rushing in and um, causing severe "internal" damage. Jumping from over 50 feet is ill-advised as it will almost certainaly break something other than your legs (spine) unless you hit at exactly the right angle. At 120 MPH you may not be able to adjust yourself by the time you realize that you're going to enter at a slight angle thanks to that last second cross breeze.
Interestingly though, according to the same book you can probably survive a 50 foot fall into a dumpster of boxes with few complications.
"So I look at something like this and go how will this advance mankind. The only answer is that it will not. This is like trying to balloon around the world. I think subjuects like this have no0 relevence on slashdot. He could take the money that he is squandering on this and give it to doctors without borders and actually do some good in this world. Isn't it time that postmodernism died."
You know what the moral difference is between robbing someone on the street at gunpoint, and using your government representatives to do it for you?
None.
What you state is VERY contrary to the spirit of freedom and individual liberty. What someone does with his own time and money is no business of yours at all.
How about your own life? That money you spent on that new RAM upgrade could have gone to help AIDS victims. That money you blew on beer and pr0n magazines could have gone to help the homeless.
See what I mean? This is, in essence, what socialism is: A central comitte decides what is done with money, property, and individuals, NOT the individuals.
I don't think that is what you are advocating, at least, I hope not...
If not for the individual freedom the USA is supposed to stand for, and the incredible spirit of adventure and creativity this spawns, the world wouldn't have had:
Charles Lindburgh
Wilbur and Orville Wright
Who both did things that were thought to be nutty at the time.
There is a reason why most great inventions of the past 150 years have happened in America. One word: Freedom.
Freedom to do with what is yours, and what gifts you have, as you will.
Corporatism != Free Market
How does a chute become frozen? Last time I checked nylon was already "frozen" at room temperature. ;-P
If you don't understand any of my sayings, come to me in private and I shall take you in my German mouth.
check out his home page:
e s/ gb_accueil.html
http://www.legrandsaut.org/
or straight to the english version:
http://www.legrandsaut.org/ressources/gb/gb_pag
He has some movies and facts and explanations and interviews....etc
few on land.
At 25,000 feet, the earth's atmosphere is significantly thinner than at ground level. So there's an interesting effect going on here: When the skydiver jumps from the plane, he'll accelerate until he's falling at "terminal velocity".
But as he falls, the atmosphere will be thickening around him, and the "terminal velocity" will decrease. Which is kind of cool, because he'll be slowing down as he's falling!
The atmosphere is like a big, airy sponge around the Earth...
Those who can, do. Those who can't, simulate.
Well...He may get to hold the record for highest skydive but *I* hold the record for parachuting night pukes.
No one has gotten sick jumping out of an airplane at night as many times as I have.
I keep waiting for someone to try to break my record. They are all afraid to try!
See it here: http://AICommand.com/PukeDuke.htm
Guru312
I just went skydiving for the first time yesterday.... albeit I only jumped from 10,000 feet... but the experience is undescribable. To all other slashdotters, I recommend that you give it a shot, even if you only jump from 2 miles, and not 20.
The sound heard on the ground as a "sonic boom" is the sudden onset and release of pressure after the buildup by the shock wave or "peak overpressure." The change in pressure caused by sonic boom is only a few pounds per square foot -- about the same pressure change we experience on an elevator as it descends two or three floors -- in a much shorter time period. It is the magnitude of this peak overpressure that describes a sonic boom.
now, all this relies on air pressure! If our skydiver hits the speed of sound up where there isn't any air to speak of, then he's not going to experience much of a boom at all now, is he?
This is not to say nothing of the fact that the boom appears to occur behind the cause, from the pilot's, or in our case the intrepid colonel's perspective. (that is, he is moving away from the sound at the speed of sound.)
NO BOOM PEOPLE, GET IT?
This comment is fully compliant with RFC 527.
I like this picture better.
Bleh!
GE once designed a device called the MOOSE, to allow astronauts to bail out from orbit and re-enter the Earth's atmosphere with little more than a space suit and plastic cocoon (remember that early heat shields where basically a big slab of high-temperature plastic that would flake off during re-entry).Here's one link about the MOOSE: http://www.boggsspace.com/strange_but_true.htm
According to the Worst-Case Scenario Survival Handbook
As a licensed skydiver, I will say that the Worst-Case Scenario Survival handbook is full of shit. They have a section on how to survive if your parachute doesn't open; part of what they tell you to do is signal to other jumpers in the air that your parachute won't open, dock on them, and hold on to them until landing. First of all, everybody else will have deployed by the time you realize you're in trouble, and even if there were people with you, you wouldn't have time to dock onto them, get a good grip on them, and let them pull. It would take a VERY good grip on them too -- the deceleration of them pulling with the added weight of you hanging on would make holding on a bit difficult.
What they don't tell you is what you are taught over and over and over again during your student training -- if your parachute doesn't work, pull your friggin' reserve!
It is blatantly obvious to me that whoever wrote that book never took a lick of skydiving training. They have NO business telling people what to do in a situation like that. Their advice wouldn't help you; it would more than likely kill you. Look at this book as nothing more than a humor book...you're putting yourself in danger if you take it seriously.
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of the Corporate States of America...
Marc! Marc Fleury! Vous etes trop age! Restez ici a Atlanta, et gagnez un grand vie!
668: Neighbour of the Beast
you have that wrong, it's He's sure to make an impact on the skydiving industry^H^H^H^H^H^H^H^H^H^H^H^H^H^H^H^Hground.
Here's some examples from http://www.urbanlegends.com/death/falling_terminal _velocity.html
This is what the Guinness Book of Records has to say:
It is estimated that the human body reaches 99% of its low-level terminal velocity after falling 573m 1880ft which takes 13-14 sec. This is 117-125mph at normal atmospheric pressure and in a
random posture.
(At the 1100 ft Emley Moor TV mast near me they reckon that you would reach terminal velocity (great term) well before hitting the ground)
Longest fall without a parachute:
World: Vesna Vulovic (Yugoslavia, wherever that is now), stewardess in a DC-9 which blew up at 10160m 33330ft over Serbska Kamenice, Czechoslovakia, 26 Jan 1972.
UK: Flt-Sgt Nicholas Steven Alkemade (d. 22 Jun 1987) from a blazing Lancaster bomber at 5485m 18000ft over Germany (near Oberkuerchen) on 23 Mar 1944.
On a mathematical note, the acceleration force is always constant, whereas the drag increases as the square of the speed. The line reaches an asymptote at about 125mph. Interestingly though,
it is actually the 0mph bit at the end which actually kills you.
Love many, trust a few, do harm to none.
It's been done before, but, there's no way you can hold on to the other person with hands alone. Put your arms inside their harness, entangle as much as you can, wait for them to pull, hope your arms don't break. Now, providing the canopy and lines hold, you have a chance to survive, with modern small <120sqft canopies the chance isn't that big, but there's at least a chance.
Microlines would prolly be very painful for a brief moment until they snap.
Although, the technique is, as you said, pointless really, no one will be around. Once your main has failed, you deploy reserve, if that doesn't work, your buddies will most likely be long gone already, and on a normal jump you'll be at <2000ft with <10 seconds until impact...
Wax-Museum Fire Results In Hundreds Of New Danny DeVito Statues
How hot would the surface of ones clothing/body become while traveling at mach 1.68 due to friction with the air?
It's a good story so I don't want to Lone Gunman it. Suffice it to say, no one gets killed and those involved weren't QUITE that stupid. There is a true story that gave birth to the urban legend. What REALLY happened isn't quite like the parent quoted Legend.
. ht ml
http://www.wagoneers.com/pages/RocketCar/rockit
However, you're absolutely right in that it's not that hard to safely dive from much greater heights. I've personally seen people do 30 metre dives at acquatic shows.
Any sufficiently advanced technology is indistinguishable from a rigged demo
--Andy Finkel (J. Klass?)
There's an article here on a different skydiver (mentions Fournier and another attemptee, too) shooting for the same record.
"If her plans succeed, on Sept 3, 2003, she'll ride a balloon to 130,000 feet, jump out in a McConnell Air Force Base pressurized space suit and free fall to Earth nearly 25 miles below -- landing somewhere within 70 miles of Wichita."
Slashdot's token middle-aged housewife
Going down isn't the problem. If the shuttle were geosynchronous, no problem.. if you had space suit, you could make the jump no problem (well, very little problem)..
But the shuttle is also moving around the earth VERY quickly.. something like 17,000 kph (feel free to correct me), which would kill you pretty much instantly when you encountered the atmosphere, and had to slow down your sideways speed.
Whoever stated that signature sizes should be limited to one hundred and twenty characters can just go ahead and kiss my
"Well, actually his max speed will be high up and near the earth the atmosphere will have slowed him down to terminal velocity."
at that high altitude, mach 1.6 IS his terminal velocity.....
The U.S. Army did this stuff back in the late 60's, only it was at 75-100K.
That was at 75 000 to 100 000 feet. This is to be done at 41 000 meters. There are just over three feet in a meter. Do the rest yourself.
Since he will break the sound barrier and eventually start to slow down, he could sing a close harmony duet with himself.
Cool.
I am a Karma Library.
First time I read the story, I thought it said "a retarded French army colonel who is soon to make a free fall parachute jump from 25 miles up."
AJS
The previous records he'll be breaking were set in the 60's, the last being in 1966. What's the deal? Have there just been two generations of lamers?
My God, it's Full of Source!
OUTSIDE_IP=$(dig +short my.ip @outsideip.net)
It's the edge of space. To protect yourself at this altitude you use essentially a space suit. This gets past all the issues of lack of oxygen, decompression etc.
You're right there is a reverse effect at high altitude. Climbers need to acclimatize properly otherwise they risk problems from oxgen deprivation and a rather nasty problem where the brain swells.
In standard parachute jumping though the exposure is not long enough for these problems to be apparent. The only time problems occur is when you go from the altitude metioned here. Instant death from lack of oxygen, and freezing is pretty assured if you tried going from this height without some protection.