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Skydiving Across the English Channel
loonix_gangsta writes "Felix Baumgartner, an Austrian, has become the first person to skydive 35 km (22 miles) across the English Channel. Wearing a jumpsuit with a large carbon fin strapped to his back he reached speeds of up to 360 km/h. The whole flight took approximately 14 minutes. The newsitem is being covered by the BBC, SkyNews
and CNN."
Already been (more or less) done. Back in the '60s, Some Air Force guy jumped out a balloon at aroung 150000ft (IE: 30 miles). No heat shield needed.
TODO: Something witty here...
Exactly! The BBC article mentioned that he was in "free fall"! I've got about 900 skydives, and if you've got wings attached to you, that ain't free fall... at least it wasn't when I was skydiving.
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The pioneer of this idea was Leo Valentin. He made several rigid wing skydives in the 1950s.
Since your replies seem to suggest your sincere, I thought I'd give a reply.
Jumping from the height this guy was on, means you have less drag, but the drag increases when you go lower, until he reaches the lower parts of the atmosphere where unpowered flight seems to be limited to about 220kph. Now would he have jumped out at 30km height, he would have broken the sound barrier and then, slowed down to 220kph.
This ofcourse holds untill the density goes (quite abruptly) up to that of solid rock, at which point velocity goes down to zero.
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Looks like a pretty good extreme sport.
:-)
Aerodynamically though, a glide ratio of 1 in 4 is not all that flash. A paraglider will make 1 in 8, so he could have flown that from 15000 ft without freezing his b******s off
Then again, a decent glider will do a good 1 in 50, meaning he could go 270 odd miles from 30000 ft. If only you could arrange a raised platform to collect cheap wine from on the way past, you could manage a good five round trips!
Actually, your average A320 will do 1 in 20, so you could fly that a hundred miles from that high up, after all the engines dropped off.
If this is a troll, I'll bite, but since there are two comments in the same vein, I don't think it is. Unless the trolls are teaming up.. dear god..
Speaking from skydiving experience, if you open your parachute at 360kph, the parachute will be ripped right off your back and probably break a few bones in the process.
Even during a "normal" skydive the diver can accelerate to around 160mph (sorry for the sudden unit switch) by falling vertically. However, before deploying the parachute, the skydiver must slow themselves down by going into the "neutral" position: arched back, hands and legs out. This will slow the diver down to around 120mph, which is safe to deploy the canopy.
Buses stop at a bus station
Trains stop at a train station
On my desk there's a workstation....
Turbulence in from the wind moving around the buildings would be a problem, that would probably make it as bad of an option as jumping.
l oh a/terrain/terrain.html
l if t.htm
Plus a glass desktop cover is going to be heavy and it don't have an airfoil to it so it's going to drop like a piece of glass and get a flutter to it.
http://response.restoration.noaa.gov/cameo/dr_a
"Even if air flow into New York City is relatively steady and the winds predictable, ALOHA's first assumption is not likely to be met within the city itself. Buildings may block and divert the wind. Air flowing past large obstructions such as buildings forms into turbulent eddies, just as eddies form immediately downstream of a boulder or bridge piling in a river. Air flowing across an urban landscape composed of many buildings breaks up into irregular patterns of eddies of various sizes, speeds, and strengths. Winds blowing through city streets can speed up, slow down, and markedly change direction. In fact, wind blowing past an obstruction such as a building sometimes can completely reverse direction. "
"New York City contains many "street canyons" long, straight through streets bordered by tall buildings. A street canyon can funnel the wind at a speed and in a direction different from what a user may have entered into ALOHA. Similarly, it can act to channel a cloud. The cloud, prevented by the walls of buildings from dispersing in the crosswind direction, may travel much farther downwind than ALOHA would predict before diluting below the level of concern."
That link is in relation to computer modeling of NBC weapons release in an urban setting, but it talks about the complexity of winds in a city.
Velocity doesn't make something fly or glide, it's the lift provided from the wing. The basic idea is that a flow over a curved surface has lower pressure than the flow over a flat surface, so you curve the top of a wing and the lower pressure there allows the wing to create lift. The faster the flow is the more lift you get, which is why aircraft need engines to provide foreward movement.
http://www.aa.washington.edu/faculty/eberhardt/
Here is Leo Valentin's 1950s version
On a normal skydive, about 90-110mph, depending on the plane. No idea for this jump, considering the special nature....
Buses stop at a bus station
Trains stop at a train station
On my desk there's a workstation....
BBC says:
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Think like a man of action, act like a man of thought.
Actually, if you'd read up on your WWII history, you'd know that gliders were acutally an integral part of the D-Day invasion in 1944. They were sent in before the the land-invasion and knocked out communication lines to prevent the beach-head forces from calling for more re-enforcements.
It acutally turned into a rather big debacle as many of the gilders did not perform well, killing their soliders, and many that did operate correctly did not make the designated target, landing miles and miles away from where the soldiers were supposed to be.
Unless she hired a dropzone to do something special for her somewhere other than a dropzone, somebody on "the boards we frequent" i.e. dropzone.com or rec.skydiving would know something about it. For example, we have verified information that Tom Cruise is or was a skydiver. I've seen pictures of him doing it. Those pictures look like he's using student gear so I don't know how far he got. An instructor I know took Cameron Diaz for a tandem. These are verifiable.
If Jolie was really a skydiver, she would jump at least occasionally at an established dropzone, unless there's some secret club of famous people who skydive. Yeah, sure.
Just because you've made one or two jumps does not make you a skydiver, press statements and personal bragging notwithstanding. To qualify to do the jump in Tombraider 2 would take about 500 skydives (recommended) just to be qualified to jump the wingsuit. Some people have done wingsuit jumps with less, but a couple tandem jumps or being fresh off AFF or even a B or C license is not going to cut it.
Peter
AFF, Tandem instructor
Got a couple Birdman jumps too
Now would he have jumped out at 30km height, he would have broken the sound barrier and then, slowed down to 220kph.
Mach I at 30 km (18.6 miles) is about 675 mph. He was travelling, at his fastest, at 360 kmh (200 mph), nowhere near the sound barrier at any altitude. The sound barrier increases and decreases even as altitude increases, but it never goes lower than about 660 mph. Here's a chart of Mach 1 at different altitudes.
(On an entirely different note, has anyone besides me noticed that the quality of Slashdot moderation has degraded over the last year or so? I haven't been "assigned" mod points since the great move West, but I know I used to do a better job than what passes for moderation these days. The mod system needs something way much more effective than the current M2 system which does absolutely nothing. I mean, we're talking about something fundamental as the speed of sound.)
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As long as you don't try to stick your arms through the shock wave, you'd be fine. Just keep 'em by your sides. A blunt helmet would encourage the formation of a shock wave normal to the direction of travel. The big problems with the early transonic planes occured because their wingtips were in the path of the shock waves, causing very seriously bad things to happen to the lateral stability of the aircraft.
Why yes, I AM a rocket scientist!
30 miles in a HALO isn't unheard of, just depends on the winds and the skill of the person using the chute. There is no need for radar absorbing materials. Radar gets a skinpaint on metallic objects really well. Organic material is much harder to spot with a radar. Parachutes are 99% non-metallic. Biggest concern would be ammo, it would give off the largest signature.
A more interesting skill in HALO is the ability to flair the chute right before you land. Basically, the diver creates a cushion of air which they can ride on for hundreds of meters. It tweaked me out the first time I saw it. They trap air between the chute and the ground, and move extremely far just a couple feet off the ground.