Are you guys following this Felix Baumgartner breaking the sound barrier stuff?
I’m fascinated by it. I discussed it in my calculus class yesterday and the kids loved it.
Is this thing whole safe? I’m guessing that what happens is he gets up to some crazy speed because of the lack of air resistance that high up and that he’ll then slow down when he gets farther into the atmosphere. Is that right?
(Almost went with “Up through the atmosphere up where the air is clear” but my Mary Poppins references never go over so well here.)
Hunter Gathers
I personally think he’s bugfuck crazy. But if he wants to pick an expensive fight with gravity, more power to him.
Culture of Truth
In space, no one can hear you scream
Dr. SkySkull
As a skydiver and physicist, I would say that your statement is exactly right. I suspect the biggest risks involve equipment failure. There’s also the fact that he has to be careful when exiting the capsule — due to the lack of air, any inadvertent rotation he creates on exit will stick with him until he gets into thicker air.
Oh, and unlike most skydives, he probably has a very poor idea of where he’ll be landing.
Joel
It’s amazing to think that Joe Kittinger’s Excelsior dive from 50 years ago is still the height record.
Mardam
That’s my guess. There is a terminal velocity at atmospheric pressure. And it’s nowhere near the speed of sound.
As far as safe goes, the sonic boom actually takes place behind the object, as air rushes in to fill the “vacuum”, much like a thunderclap. Unless he goes from almost zero pressure to one atmosphere all at once, like hitting a wall, I don’t see a problem. Not that I’d want to try it or anything.
General Stuck
Long as he has lots of O2 and suntan lotion, he should be good to go. Oh yea, and his parachute opens. If he deploys it too high up, it might not inflate right a way, and do what is called a “cigar” in skydive lingo. That is not good, but likely will fill up when there is enough atmosphere.
Cacti
This stunt kind of reminds of the joke, what are a redneck’s last words?
“Hey y’all, watch this!”
Bill D.
Nitpicking point here. . . there will be a near-lack of air resistance not a total lack, or else he would go even faster. There is still air up there, just very, very little.
Keith
It’s not safe by nature. The balloon is extremely fragile (but, then, the guy is wearing parachutes), but he is going to a level where the solar radiation is intense (you can sweat while it’s below freezing). If his stabilizing parachute fails, he goes into a 200G tailspin and dies. If his pressure suit rips, his blood boils from the low pressure. The guy even has to be on a special diet to avoid building up gasses (that could expand) in his intestines.
In short, it takes a TON of redundant engineering just to lower the risk of leaving our comfortable low-energy/high-pressure bubble on the ground.
c u n d gulag
Mary Poppins references?
No wonder they renamed you Metrosexual… Doug J!
By the way, I love that movie. And “Chitty Chitty Bang Bang,” too!
Love,
Metrosexual c u n d gulag.
Poopyman
Hmmm. Is he really going to go supersonic? What’s the plan for slowing down before he opens his chute? I seem to recall that air friction causes quite a bit of heating. Is the theory that because he’s falling relatively slowly that air friction is going to be negligible enough to be discounted?
Culture of Truth
I believe his biggest dangers are equipment failure, especially when he first exits, and a spin out.
Also, birds.
rlrr
@Bill D.:
Even the ISS experiences atmospheric drag…
Villago Delenda Est
@Cacti:
“Here, hold my beer, and watch this!” is a better joke.
Wouldn’t the speed of sound be somewhat lower at lower atmospheric densities? I’m not a physicist by any stretch of the imagination, but I think once you reach hit thicker atmosphere you’d slow down. Not by much, but enough to squash this “faster than the speed of sound” stuff.
gnomedad
@General Stuck:
This must be some strange use of the word “safe” I’m not familiar with.
Chris
Forgive the probable stupidity of this question but…
… if you jump from the edge of space, don’t you burn up in the atmosphere?
(Beyond that, man. I have a fear of heights and I’m getting goosebumps just thinking about this).
rlrr
@Chris:
No, he will reach nowhere near the speeds where burning up on re-entry will be an issue. Spacecraft re-entering the atmosphere from orbit start out at 17,500 mph.
General Stuck
Jump school motto
After enlisting in the 82nd Airborne Division, I eagerly asked my Recruiter what I could expect from jump school. “Well,” he said, “it’s three weeks long.” “What else,” I asked. “The first week they separate the men from the boys,” he said. “The second week, they separate the men from the fools.””And the third week?” I asked. “The third week, the fools jump.”
Chris
@rlrr:
Oh, so that’s why. Thanks!
Culture of Truth
If this works, we can try with it wall street next.
It would give a whole new meaning to ‘jump you fu—-ers’
Chris
@Culture of Truth:
Actually, even if it doesn’t work, we can still try it with Wall Street.
General Stuck
@gnomedad:
Yea, well, you obviously don’t speak DougJ.
MikeJ
@Dr. SkySkull:
Other high altitude jumpers use a drogue to keep their orientation correct. Of course going for a speed record I don’t know if he will.
The Dangerman
@Keith:
Damn, gives new meaning to silent but deadly.
srv
Some math for your victims:
tscm.com/mach-as.pdf
And Mary Poppins must not have gone more than a couple 100 feet AGL. Any pilot can tell you the sky ain’t very clear.
gnomedad
@General Stuck:
It’s a line (probably my favorite) from the Hitchhiker’s Guide.
Culture of Truth
The best part of this is he’s landing in a kiddie pool for Americas Got Talent
dmsilev
@Villago Delenda Est: The math is worked out here, but the short version is that the speed of sound in air scales like sort(T) (T in absolute units), so in the cold upper atmosphere, it’s lower than what it would be near the surface.
catclub
@c u n d gulag: The child catcher is deeply disturbing. And don’t ask me to watch Wizard of Oz, the part in the forest, just _before_ the monkeys.
Cermet
Besides vastly lower air resistance were he will ‘jump’, the speed of sound is lower the thinner the air becomes – lower denisty. The major danger is that he will start to spin – as pointed out, without enough air resistance, the spin cannot be controlled or slowed. From all experts, blood will not “boil” if his suit rips and he is exposed to the local vacuum (even at the ISS – the body keeps the blood’s pressure, well above the low level required to cause it to boil. Of course, the lack of oxygen would quickly kill him if the suit ripped.)
maya
Shouldn’t he be selling something on the way down? Or meeting up with the Aflac duck?
Roger Moore
@Villago Delenda Est:
Not exactly. The speed of sound goes down as you go up in the atmosphere (at least into the stratosphere), but it’s mostly a temperature effect rather than a pressure effect. It’s going to be cold at 23 miles, which will depress the speed of sound a fair bit.
catclub
@srv: Yes, but before we polluted it, it was very clear. The flight moratorium after 9/11 showed pretty substantial effects, didn’t it?
Eric U.
@General Stuck: I knew a guy who went to jump school and broke his leg. He broke his leg when someone stepped on his heel on the steps out of the jump pit.
Interrobang
@General Stuck: I agree with this. My dad is a retired commercial pilot, and I figure anybody who jumps out of a perfectly operational airplane needs their head read.
Roger Moore
@Chris:
I wouldn’t want to give Wall Street an expensive experimental experience like this if I thought they were likely to survive the experience.
The Moar You Know
Been following this for years – the original date for the jump was back in 2010.
Good lord, no. He could easily die. In about 10 different and exceptionally horrific ways.
NCSteve
@srv: In London in 1905, anything above the coal and fog miasma was “up where the air is clear.”
Roger Moore
@Interrobang:
Good thing he’s jumping out of a balloon, then, isn’t it. Also, too, doesn’t that make this a perfect topic for Balloon-Juice?
General Stuck
@Eric U.:
Chris
@Roger Moore:
I was wondering how long it would take for someone to FTFY that. Your comment afterwards made me LOL, too.
? Martin
Yes, that’s right. It’s not really that safe as Keith above notes. He will slow down as the atmosphere gets denser – that’s the one thing working in his favor.
@Villago Delenda Est:
It’s a bit complicated. The speed of sound is higher at lower elevation, bottoms out around 15,000 feet and then starts going up again at much higher elevations (30K) then goes back down again around 75K, I think, then goes back up again.
The ‘speed of sound’ is really a measure of the compressibility and density of the fluid. These are also affected by temperature – which is really what causes that variability above. As you get up near airline altitude, the air heats up again due to the ozone layer, and then it cools down again up above that level as the atmosphere gets so thin that molecule collisions get rare. That variability has other interesting effects – the inflection points on the speed of sounds serve as kind of a mirror for sonic booms. A loud sound in the low atmosphere will somewhat refract off of that point where the speed of sound changes back toward the ground, and one in the upper atmosphere will do the same back upward. As a result you get a kind of sound echo. This is what makes thunder roll the way it does when it’s off in the distance, but the development of supersonic aircraft is somewhat complicated by how to control the sonic boom coming off the plane so that there is minimal notice on the ground.
arguingwithsignposts
Don’t think the alienologists aren’t having a field day with that.
Butch
Sorry, but I just don’t see the point.
? Martin
@Butch:
Same could be said about this blog, and yet here we are.
neographiite
Hey, now, Doug, no apophasis on this blog.
Death Panel Truck
@General Stuck: My old man was a fool. He graduated from jump school on August 31, 1945, just a tad late for combat. He went to Japan with the 11th Airborne Division, and came home 8 months later, arms covered with tattoos. His mother was not pleased.
Butch
@? Martin: Am I not supposed to have an opinion?
Bill K
As a parachutist, I know normal free-fall from 15,000ft is 120mph. That is in the “frog” position. You can achieve about 200 mph in the streamlined position (head down, arms at your side, legs straight) that Felix will be using. I have to doubt that even in the thin upper atmosphere he can achieve the speed of sound (~760mph) but I think it is cool that he is trying it.
Robert Sneddon
@General Stuck: A friend of mine had transferred into the 3rd Parachute Regiment (AKA 3 Para) just before the Iraq clusterfuck was ramping up back in 2002. While he was going through the jump qualification course all the C-130 Hercules planes in good condition had flown off to RAF Akrotiri, staging for the upcoming sandland festivities and leaving the jump school with the back-of-the-hangar planes to use for training and qualification. As he put it, it was a good thing everybody on board was wearing parachutes.
? Martin
@Butch: We’ve all got opinions. We’d crash the internet if everyone itemized the things they don’t care about. If you don’t see the point, move onto the next thread and give us your opinions on things you do care about.
The Moar You Know
@Butch: The reason they did the first jump tests back in the 1950s is that they simply did not know what would happen to a human being who had to bail out of an aircraft or spacecraft at high altitude and high speed. To a large extent, we still don’t know a lot about that, and what we really don’t know – and what Mr. Baumgartner is soon going to find out – is what happens to a person when they break the sound barrier without an aircraft around them.
The hypothesis is, that with the equipment he is wearing, that Felix will live and not die. He’s going to test that hypothesis.
This is science in its purest form. Usually this hypothesis-testing shit is pretty boring. This particular test won’t be.
Citizen_X
Hadn’t heard anything about this till this thread.
And after reading through it, all I could think was, jeez, would it kill anybody to put up links? Here: here’s a good background video for the jump, putting it in context with Col. Joseph Kittenger’s (current record-holding) jump from 1960.
Kittenger is deeply involved with this present attempt. Good to see.
Mardam
@Chris: You aren’t going fast enough to build that kind of friction. Remember, spaceships are travelling at +17,000mph (orbital velocity), or even faster if they are coming from outer space. He’s travelling at less than 1000mph.
Spatula
Google and Wikipedia are your friends.
Waldo
I am not a physicist, but I think what will happen is that he will accelerate to Mach I, at which point he will burst into flames. Then he will return gently and slowly to earth in a sprinkle of ash.
Again, I am not a physicist.
Ole Phat Stu
The speed of sound above 36000 feet is 573 knots.
The outside temperature is -56°C.
Friction heating is 23°C at Mach 1 there.
All assuming I did my sums right ;-)
Maude
This is about as safe as Slim Pickens.
mclaren
The big problem is that turbulence could cause Baumgartner to spin so rapidly that the blood pools in his extremities and he passes out or dies from lack of oxygen to his brain. That’s fixed by not spreading his arms and legs, though.
Other than that, there’s little about it that’s dangerous. The guy has a pressure suit, he’s got oxygen, he’s well insulated against the cold. The only dangerous aside from the spinning issue involve cold and lack of oxygen, which he’s dealt with.
brettvk
Oh, sweet Jesus jumping without a parachute — this stunt is sponsored by Red Bull? That should spawn a lot of interesting experiments in America’s frat houses.
BruceJ
@Dr. SkySkull: This is what almost killed the last guy to try this; hea;’s coaching baumgartner in this thing, and why they’re being VERY careful to not add any spin@Roger Moore:
Moreover, it’s a balloon that’s going to keep going until it pops and falls back down. Baumgartner’s jumping before then, but this is the same fundamental process behind the current fad of attaching video cameras (to record it) cellphones (to find it later) into styrofoam containers tied to weather balloons and taking your very own ‘space pictures’
Fort Geek
@Roger Moore: Let ’em use their “golden parachutes”…converted to gold.