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Skydiver To Break Sound Barrier During Free-Fall
Hugh Pickens writes "Over fifty years ago, American Joe Kittinger made history by leaping from a balloon at 102,800 ft, and although many have sought to repeat the feat, all have failed. Now, BBC reports that Austrian extreme sportsman Felix Baumgartner will try to break the long-standing record for the highest ever parachute jump, skydiving from a balloon sent to at least 120,000 ft, and it is likely that 35 seconds into in his long free-fall of more than five minutes, he will exceed the speed of sound — the first person to do so without the aid of a machine. 'No-one really knows what that will be like,' says Baumgartner. Although challenges in the endeavor include coping with freezing temperatures and ultra-thin air, a key objective for Baumgartner will be to try to maintain a good attitude during the descent and prevent his body from going into a spin and blacking out. 'The fact is you have a lot of different airflows coming around your body; and some parts of your body are in supersonic flow and some parts are in transonic flow. What kind of reaction that creates, I can't tell you,' adds Baumgartner."
It's really going to hurt.
"The average reporter we talk to is 27 years old......They literally know nothing." - Ben Rhodes
So I guess I'm not the only one to think this guy is going to die doing this stunt.
Tesla was a genius. Edison however was a overrated hack who liked to torture puppies.
Just like car racing, I want to watch.
Working on new views of old physics at http://VisualPhysics.org
Am I the only one that though of the space diving scene from Star Trek 11?
If there's enough atmosphere to lift a balloon, there's enough atmosphere to transmit sound.
http://alternatives.rzero.com/
Failed?!? How can you fail that? Throw yourself self off the balloon and miss the ground?
/greger
If there's enough atmosphere to lift a balloon, there's enough atmosphere to transmit sound.
And the balloon would also be the machine he is 'not getting aid from.' he will exceed the speed of sound — the first person to do so without the aid of a machine. (from the /. story)
Home of The Suki Series
Right, a balloon is not a machine. Way to be redundant.
... will he bounce?
Meh, it's a question of technicalities. Gravity is the force that will cause him to break the sound barrier (and perhaps the thin air - lack of resistance). A machine will not be used to accelerate him. It will give him tremendous potential energy, however. Anybody want to calculate that?
he will exceed the speed of sound — the first person to do so without the aid of a machine.
He's using a machine. It's a balloon that sends him up 120,000 ft.
Not just that, but undoubtedly he'll have a suit to keep him from freezing and an oxygen supply to keep him from passing out. So if you want to be pedantic, he has plenty of 'machines' aiding him, but nothing with a motor, which I think was the point.
Test the survivability of this by using a dummy with G-force sensors (just like we see on Mythbusters).
Then, if all goes well - try the stunt.
And please, use some kind of stabilizer to make sure you don't turn into a frisbee.
I do see potential in this 'experiment' if anyone ever needs to bail out on spaceship2.
Presumably, he's planning on leaping from the balloon when it reaches its maximum altitude for the flight and is about to start it's inevitable descent. At that point his vertical velocity will be pretty near zero and so other than any residual lateral drift coming from the balloon any speed achieved will be entirely due to the influence of gravity. What isn't clear is whether he will be exceeding speed of sound at sea level, or just at his current altitude during the descent as well (it's not possible to do the former without also doing the latter).
UNIX? They're not even circumcised! Savages!
I'm going to guess that he doesn't break the sound barrier. The term "barrier" isn't entirely fanciful, as power required to go faster increases enormously as you approach it.
On the other hand, if he DOES break the sound barrier, I'm going to bet it does him some injury.
If my calculations are correct, it's 623 ergs/quartic coloumb-acre.
PE = mgh ~= 76Kg*10m/s^2*120000ft*0.3m/ft = 27,360,000Nm. This is the equivalent energy of a man the same weight traveling at about 848m/s: over twice the speed of sound. (to be fair I used the minimal mass of the average human male) I consider this significant help from technology.
@humanity: *facepalm*
Meh, it's a question of technicalities. Gravity is the force that will cause him to break the sound barrier (and perhaps the thin air - lack of resistance). A machine will not be used to accelerate him. It will give him tremendous potential energy, however. Anybody want to calculate that?
About 26 megajoule.
(If you want to check the calculation: His weight is 73 kg)
The Tao of math: The numbers you can count are not the real numbers.
Actually, I wonder about the heat from the friction of the air for that long. in addition to the freezing temperatures prior to high velocity.
@humanity: *facepalm*
More to the point, let's say he intends to go sonic at 20,000 feet. In falling 100,000 feet he'd reach a speed of 2530 ft/sec if there were no air drag. The speed of sound at that altitude is 1036 ft/sec, so he has a chance, depending on how little drag he can achieve.
As he comes down in altitude, the drag and the speed of sound both go up, so it becomes a much harder calculation. There is an abrupt drag rise right around Mach 1, so there's a significant chance he could stabilize at, say, Mach 0.98 and be unable to accelerate further.
rj
I realize that Terminal Velocity will be higher with less air density, and the speed of sound should be lower, but do they both change so much that this is actually possible?
Guns don't kill people; Physics kills people! - John Lithgow as Dick Solomon on Third Rock From The Sun
If you go supersonic, there will be sound. Trust me on this.
rj
I'm sure they mean the speed of sound at his particular altitude. Joe Kittenger reached 614 mph during his freefall in the 1960, which is roughly Mach 0.8 at sea level. At around 35,000 feet the speed of sound drops to around 650 mph. At higher altitudes, the speed of sound actually increases for awhile.
Yes, but will anyone hear it?
I've got 101 mod points and you can't have them!
Isn't "terminal velocity" lower than the speed of sound?
During the fall, how far could he drift from the balloon's overhead position? A few miles? Tens of miles?
Prisencolinensinainciusol. Ol Rait!
Pretty good information about high-altitude skydiving here: Speed of a Skydiver
http://www.geoffreylandis.com
Oh, there will be lateral drift due to the wind at maximum altitude, versus the wind at every altitude below that.
For reference, the speed of sound is _slower_ at higher altitudes. There is a chart at http://www.aerospaceweb.org/question/atmosphere/q0112.shtml. And for him to achieve transonic speeds for parts of his body but not other parts, he'll be breaking the local sound barrier.
Breaking the sound barrier also produces a _profound_ braking effect: you wind up providing tremendous power to compress the medium in front of you. All that energy that goes into the shock wave and the turbulence as you pass through the medium and the "sonic boom" itself, is a continuing drain on your kinetic energy. So I suspect his speed will max out at or barely above the sound barrier, and he'll certainly slow more rapidly as he hits thicker air and experiences more drag, slowing all the way to his freefall velocity in the denser air. That depends a lot on the shape of his suit: I'd expect him to want a high drag suit for maximum fall time.
If you fart while exceeding the speed of sound, will it make a noise?
__ Someday, but not this morning, I'll finally learn to use the preview button.
If a balloon counts as a machine, so do soap bubbles...
One that hath name thou can not otter
I think this has to be considered as a Darwin Awards nominee...
Apparently you never learned about significant figures.
Strictly speaking the record will be for highest parachute jump. Assuming he's alive when he jumps he should get the record, even if he lands in several pieces.
Aside from the air friction, it's going to jolt like hell when his chute opens and he starts to decelerate.
This assumes a spherical earth and neglects relativistic effects.
Also those decimal places are wrong,
The smart one may not be who you think it is.
Always back up, never back down. ---- Think you're cool 'cos your uid is prime? Take mine, modulo the one digit integers
" a key objective for Baumgartner will be to try to maintain a good attitude during the descent"
At first glance, I thought I saw "maintain a good ALTITUDE". Jumping out of the balloon would all but dash any hope of that. That being said, I'd have to say that my attitude would be pretty piss poor as I froze my privates off while descending at super sonic speed.
I hope to god he's not wearing a red shirt.
The Difference between a bad golfer and a bad skydiver? one goes *Whack*... "D@mn". the other goes "D@mn"...Whack.
Is 3rd person life insurance legal in Australia?
I mean they only ask if one has dangerous hobbies like sky diving, right? They probably don't ask if you are doing super sonic skydiving...
This issue is a bit more complicated than you think.
What can possibly go wrong?? /. memo
from wikipedia, i pulled this sorta-definition : 'A machine is any device that uses energy to perform some activity' I guess the oxygen is pressurised, so it has energy, and it will be used to force-feed him oxygen ... And i think the balloon is a machine too ...
Yes, I'm left. You have a problem with that?
Damnit, we've lived in fear of them going 600 miles an hour in airplanes and crashing into things. Now what the fuck are we going to do when they start falling from the sky at 800 miles an hour?!
Will that still apply at extreme altitude as friction, and ergo drag, is going to be a lot lower due to thinner air?
Regardless rather him than me... also the comment from him regarding bits of his body being in a transonic and some in supersonic airflow makes me wonder if he's going to arrive in one or multiple pieces....
--- Users are like bacteria -> Each one causing a thousand tiny crises until the host finally gives up and dies.
OK, it was a deleted scene. And I think it involved actual orbital reentry in just a jumpsuit. Still, I suspect that if this guy survives, he will eventually end up attempting something like that. Does Virgin Galactic sell one-way tickets?
You can always tell because they have that Sun logo in their favicon.
Advice: on VPS providers
Funny... breaking the sound barrier when there is no sound
The sound of the skydiver screaming: "oooooooooh craaaaaaaaap!"
No. It will be expanded to normal pressure before it is inhaled. For the actual breathing the pressure of the oxygen thus is irrelevant. It got compressed to store more of it within the same volume.
Terminal velocity is cause by the resistance of the air equaling the force of gravity. Well, up higher you've got less air. Of course that also affects the speed of sound.
He will need a very pointy hat.
Ezekiel 23:20
He most likely will vibrate to death... they should test it first with a real doll.
You never do until they leave. :(
Or units.
Then I guess you better make damn sure you read all your NOTAM's aye bunky?
Yeah I am a pilot.
Hey KID! Yeah you, get the fuck off my lawn!
i'm not sure there's that much air at 120.000 ft.
The Cloud - because you don't care if your apps and data are up in the air.
Yes. Because the balloon does not propel him. That's what 'aid' means in this context. Propulsion.
I'm sure you'll find plenty of results if you search for things that get more stiff the more they're blown on.
The problem with quotes on the internet, is that nobody bothers to check their veracity. -- Abraham Lincoln
Kittinger was a contestant on the "What's My Line" game show in 1956, in honor of an earlier altitude record he set in a balloon:
http://www.youtube.com/watch?v=tNFH1Ds0rU4
Very personable guy; there's a brief interview with him afterwards.
If I ever see a NOTAM I immediately shred it. If the ship doesn't have a helipad on it then they don't need to know. Now if you were to read all your GOLDs or PURPLEs...colour me impressed.
I tried to think of a good sig, and this wasn't it.
This would really only be interesting if no gear other than a parachute was used.
I wonder if the air resistance at that speed would crush him without re-enforcement gear.
What a pointless comment.
After all, I am strangely colored.
Relativistic effects in 120,000 feet? Please, he's going around 800m/s at the fastest. He isn't a muon.
After all, I am strangely colored.
Jeez, has no one ever heard of a back of an envelope calculation? Here, let me blow your mind: Pi = 3
@humanity: *facepalm*
And by no one I mean Mr. Anonymous Coward...
@humanity: *facepalm*
and although many have sought to repeat the feat, all have failed.
Isn't this one of those thing that you either succeed or you die?
The only possible interpretation of any research whatever in the 'social sciences' is: some do, some don't
But those machines aren't helping him reach the sound barrier, they're only helping him survive the experience. He could still break the sound barrier without them, or at least his body could.
We hope your rules and wisdom choke you / Now we are one in everlasting peace
Interviewer: "Is that your crash helmet?"
Jose' Jimenez: " . . . oh I hope not."
Using:
standard atmosphere http://www.desktopaero.com/stdatm.html
Mach/altitude tables http://www.aerospaceweb.org/question/atmosphere/q0112.shtml
g acceleration http://en.wikipedia.org/wiki/Terminal_velocity
and historical stuff on Col Joe.
At 35 seconds he'll have fallen from 120kft to 80kft, going 1126 ft/s. That's Mach 1 at sea level. At 80kft it's Mach 1.15, giving some room for drag error. 10 seconds later he'd cross from stratosphere to tropopause where Mach 1 is lowest, but since it's only a matter of ~6 ft/s, this just gives him room to fall farther if need be but not required. At 80kft the dynamic pressure will be around 55 lb/ft^2, so if fully loaded he weighs more than 165 lbs he'll still accelerate some, but not after the 45 second mark. If he's outfitted like Kittenger was, he'll weigh up towards 300 lbs, and would still accelerate for some time.
At 30 seconds he'll be falling at 965 ft/s, or Mach 0.98, well within the narrow transonic region of highest pressure, "max Q". This is where aircraft prior to the Bell X-1 came apart due to the buffeting of turbulence combined with the growing bow shock pressure wave.
He can do it theoretically. The altitude is just about perfect for the attempt. I'm more concerned about whether he'll be able to keep from getting the piss kicked out of him at the Mach line. Sure, it'll be slight compared to what General Chuck punched through, but he's a damn sight slighter than the X-1. On the other hand Kittenger hit Mach 0.96 around 60kft and I see no report of this effect so maybe it's not a problem.
It may still be a problem to punch through though. There's a spike in the speed/drag curve that's greater or lesser depending on the drag characteristics (coefficient of drag of cD). If his outfit will be shaped to approximate a low cD body so much the better. Since he'll require some form of protection I doubt anyone would fault him for choosing a shape to fit his flight profile.
If he kept up his falling profile he's still slow to terminal velocity for the lower altitude, around 200 MPH, slower still if he's either braking or blacked out and spinning. Lower altitude here is taken to be where he could pop the chute and stay conscious even if he lost his mask, around 20 kft. At that altitude and speed a full open would be quite a jerk, but no more than airborne troops practice, and which I'm sure he's handled previously. If he's designing his chute to be able to be opened higher/faster should he need or want to, he'll include a drogue chute with a delay before the main, to slow him gradually to safe opening speed (especially helpful if spinning).
"I may be synthetic, but I'm not stupid." -- Bishop 341-B
He'll be in a pressure suit...... and it's not like a sudden shockwave goes through your body when you hit mach 1. You don't really "pop" the sound barrier.
that breaks the sound barrier, the brown note
Won't a high drag suit also help him stabilize himself to avoid going in to a spin? He'll need the surface area (provided by a high drag suit) where the air is thinner, I think.
If I mod you up, it doesn't necessarily mean I agree with what you've said, sorry.
FAA restricted airspace, ground level to 120,000' due to crazy guy jumping from balloon. Radius 100 nautical miles.
By what definition is a balloon NOT a machine? . . . Thought so. Wait, you say he's not getting assistance from the balloon? You mean he floated up there on refried beans and hot air? The slash/short should have been written to say "without the aid of thrust".
Always going forward, 'cause we can't find reverse.
Some footage from the original Kittinger jump are incorporated in this awesome music video by Boards of Canada:
http://www.youtube.com/watch?v=3xN3t1fSbnc
If they don't work, he'll have slowed down to low-altitude terminal velocity. But if everything works, he'll be landing at normal parachute-landing speed, so he may bounce a bit when he first touches down.
Bill Stewart
New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks
It's astonishing what lengths some people will go to, to not understand the obvious meaning what someone is saying.
http://alternatives.rzero.com/
Ha! Amateur. I had an undergrad professor who liked to say Pi ~ 10, to an order of magnitude. Estimation is a good skill to have.
snig
Not too difficult
He will need a very pointy hat.
Also it should double as a sniper rifer ... just in case he needs to fight off any alien invasions on the way down.
I want to see the scene from the movie "Heavy Metal" performed in real life. A car (not just any car, a 57-ish 'vette) drops from the shuttle, survives re-entry (with a little help from the windshield wipers to clear the char/ash), lands safely, and drives off!
Tiller's Rule: Never use a word in written form that you've only heard and never read. You will end up looking foolish.