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Stratospheric Skydiving
nikhil_g writes " National Geographic has the tidbits about an attempt that sounds as bizzare as they come. It seems to be on horizon with a US Team also planning sooner than the Australian attempt in 2002. " Feed Mag has more complete coverage as well. It's certainly a...uh...active way to spend your time.
No, it's not. WE already do stuff like this for a long time (remember, the existing record for this was set in the 1950s), it's called "HALO" jumping (High Altitude Low Open). One of the things you can do is fly yourself through the air for that time, instead of just dropping straight down. For some significant ground distance, too.
Reread your Tom Clancy books...
I am a skydiver and 2 1/2 miles high is enough for me. I watched a video on the Discovery Channel or TLC or whatever a while back on some people who jumped from this height for NASA. Exactly what are these people thinking? I have very clear memories of these NASA people actually having their packs, suits, air supply, and gear either burn up completely from air friction to their bodies not being able to handle the pressure/temperature/stress and having serious health problems, even death. Just thinking about falling that far only gives me pictures of the ceramic tiles on the space shuttle. It sounds cool, I have to agree, but the risks or simply ridiculous compared to value of life.
"An experienced skydiver, speedboat racer, scuba diver, and, before that, an insurance salesman,.."
*sigh* now if only we could get more insurance salesmen to do this.
"Millner believes that he will reach a speed of between 700 and 900 miles per hour within one minute of leaping from the balloon."
And within about that same time be carrying a small sewage plant in his undies.
Ceci n'est pas une sig.
Sorry Millner, but the seas ain't been done. We know more about the rings of Saturn than we do about our own ocean floor . . . low pressure is much easier for us to deal with than high pressure.
This is not any significant milestone. This is just a multi-million dollar thrill ride for some egomaniac.
If the guy jumped over California and rode the Jet Stream, he would probably end up... in California!
The average speed of Jet Stream is 110 to 140 knots (source here). So let's take 140 knots, which is around 4 km/min (to give you a better idea, that's 260 km/h, or 160 mi/h). According to the article, the fall should last around 10 minutes. The horizontal drift of the guy would then be:
Not bad if you consider that the guy jumps from that same distance in height. But anyway, he won't be in the Jet Stream all the way down, so the actual horizontal drift will probably be much lower.Note: I did not forget the guy's relative horizontal speed (horizontal speed within the wind, as the guy "surfs" on the airflow). That speed is just not significant compared to the speed of the Jet Stream.
--I code, therefore I am.
Terminal velocity also depends on position. The 120 MPH figure is accurate for the familiar "frog" position. The velocity is about 200 MPH for the "tracking" position, which is the maneuver you see in the movies when the Bad Guy is swooping down on the Good Guy, or when the Good Guy is swooping down to save his Buddy who fell out of the plane without a parachute.
Scratch-o-Matic
Evil is the money of root.
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For sale: parachute. Once used, never opened, small stain.
I saw a tv special about the Air Force jump. Its freaking berserk. I mean, it's cool that we can dump people off of those hieghts and they can manage to live through it, but isn't it a bit like testing how tough your toy trucks are by dropping them off higher and higher tables? When they break you make a better truck and try again?
- the-crater insurance
I dunno. My brother is Airborn qualified, as is my dad, my aunt, my uncle, and more of my family, and I think it's kind of retarded to jump out of airplanes anyway, but I suppose sending people around the world to shoot at each other is kind of dumb too, but necessary. The people doing this stuff for the heck of it, or to set a record, now that's just stupid without explanation.
Who covers their insurance? I suppose you don't need health insurance, more like hose-and-bucket-cleanup-and-truckload-of-dirt-for
Yoinks.
-- there is no point in pulling the pud... if you do it right.
This guy had some serious intestinal fortitude.
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US Captain Kittinger did this in 1960 (as mentioned in the feedmag article), and although he didn't go faster than sound back then, and wasn't dropped from as high an altitude, it's still a feat keeping in mind. Kittinger himself wrote a detailed article in Life magazine about the jump.
-Kraft
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-Kraft
Live and let live
As he descends the air density will pick up and he will slow down.
Chris Kuivenhoven is a thief, beware
In the 60's while testing Astronaut recovery/escape systems, the U.S. Air Force had someone jump from about that high up. He was testing a 3 stage parachute ( since it can't open all at once due the sheer force of the opening shock ) at the time. It was done somewhere over Arizona. They used a helium balloon to lift him up. There is even a video from a camera fixed in the balloon showing it.
And yes, he did break the speed of sound on the way down. 714 mph! Wheeee. :)
The AF Site
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Anyone jumping from that kind of altitude is going to be loaded down with a lot of life support equipment. Not much left over in terms of payload for weapons and operational equipment. There are other problems as well. When troops jump HALO(High Altitude Low Opening), what they do is jump out of the plane at every high altitiudes and freefall a very long ways before ever opening their chute. I think they jump from 14000 ft and don't open a chute til 500ft. Someone who knows the actual figures, please correct me. This happens for two reasons: A soldier dangling from a parachute has a very large visual and radar signature. And, the soldiers can jump out over friendly territory and drift during the freefall into the enemy's area. This is ideal for any kind of covert operation, or even just for any action in an enemy's rear.
Jumping from a stratospheric altitude is going to require that several chutes be opened at various altitudes to slow the jumper down, They're going to be very visible a every stage. And, that is going eliminate the primary motivation for parachute operations: stealth and suprise. Not to mention, there's a limit to how much chute you carry relative to its stopping power. Paratroopers carry a _lot_ of equipment, but there's only so much. Add life support to that, plus all the chutes for this kind of jump and you won't have much left over on the ground to fight a battle. Not to mention, the jumper is going to have to get out of their space suit once their on the ground. Presumably, the enemy is going to be looking for the jumper if not shooting at him while he's doing that.
In contrast, the force Heinlein envsioned was basically a tank force. Granted the tanks were anthropmorphic vehicles that operator wore, but the MI still had the kind of signature and hitting power of an armored force. Nothing very subtle about that. The enemy would most certainly notice the warships coming into orbit, followed by the massive signature of the MI hitting the atmosphere. To the MI that doesn't matter because they hit the ground fighting. Contemporary paratroopers can't do that. They have to secure their equipment, find their teamates, form up, check their location, and so on before they can even begin to fight. Any time paratroops have jumped into a prepared and entrenched enemy they've been cut down or captured. Meanwhile when dropped in an enemy's rear the lightly armed paratroops can use their advantage of surprise to wreak massive damage on the enemy's support and command and control systems.