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General control line discussion => Open Forum => Topic started by: Elwyn Aud on October 14, 2012, 09:05:11 AM
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http://www.youtube.com/redbull \
I hope it gets off the ground this time and more importantly gets back down safely. I read where the balloon material was about as thick as a dry cleaner bag and there was enough of it to cover 40 acres. Sure doesn't look that big. The last update said the weather hold had been lifted and they were inflating the balloon which takes over an hour.
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Only bird crap and idiots fall from the sky
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Capsule lifted off about 10:30 CDT. I think it's a little over 3 hours to target altitude.
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I think the balloon will expand quite a lot when it gets into thinner air.
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He might hit mach but it's the transition back to sub-sonic that's the concern as he enters thicker atmosphere. His suit doesn't look all that aerodynamic. Buffeting and tears/ decompression could be his undoing.
Wish him luck but I think he's nuts.
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How high's the capsule Mama? Sixteen miles and Risin'. (With apologies to Johnny Cash) Noon CDT
It's amazing how clear the video is from the ground.
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12:30 Just passed the altitude record for manned balloon flight set by the U S Navy in 1961. 113,739.9 feet
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Only bird crap and idiots fall from the sky
No Peabody...
HEROS do too!
Randy Cuberly
Airborne!!!
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128,000 feet! Wow Over 24 miles! One giant leap for a man.
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729 mph! (unofficial)
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Pretty awesome!
Thought he was a gonner when he started spinning.
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WOW JUST WATCHED THE ENTIRE THING
Ed
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That was great. Very high quality video.
Thanks for posting the link.
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They are saying the one record he didn't break was Joe Kittinger's length of time during free-fall. Kinda neat that Mr Kittinger held on to one record. There will be a press conference coming up shortly.
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Wow!! Thanks for posting that Elwyn. My wife and I both were glued to the computer screen during the entire climb and descent.
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I get nothing
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Gravity?
Weren't we tought that ALL objects fall to earth at the same speed?
Charles
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Press conference 3:30 CDT They're saying the maximum speed was over 800 mph.
http://www.youtube.com/redbull
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Gravity?
Weren't we tought that ALL objects fall to earth at the same speed?
Charles
I was never taught that. The objects have to be in a vacuum. This was proven on one of the moon missions. Might have been the same one that Allen Shepard hit the golf ball. The astronaut dropped an eagle feather and a hammer at the same time, and they hit the lunar surface at the same time. Size and weight are relative to what happens as an object as it falls back into the atmosphere as well as it's speed. The air density increases gradually, and the objects speed decreases gradually at the same time. Burt Rutan explained it at Oshkosh the year before he won the X-Prize. At the altitude and speed they are going the decrease in speed is relative to increase in air density and slows the object gradually. That is how they can re-enter the Spaceship One with what is basically a Free flight dethermalizer, or what he called the "feather mode" or shuttlecock re-entry, without any type of heat shield. I can't remember details, but to do with the term "relative airspeed." A neat example of this is the fact that he didn't break Kittinger's record for time of free fall. The first portion of his jump was in such thin or nonexistent air that he accelerated so fast, he reached the 'chute deployment altitude faster. I think he was 20 seconds short or something like that, and he was considerably higher when he jumped. The jump was pretty cool! I had forgotten about it and lucked into catching the last hour of ascent and the jump. I remember a movie from when I was a kid that was based on Kittinger's jump. I can see the actors face in my mind, but can't remember his name or the title of the movie. I gotta admire the guy and Joe's participation in the effort. When Felix was under canopy, I think I heard Joe say, " I couldn't have done it better myself!"
Type at you later,
Dan McEntee
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I'm reading on the news that he 'fell' at 833.9 mph!
Phil
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Same here. Internet News reports 833.9 mph (Mach 1.24) during a fall from 128,100 feet.
AIRBORNE!!!
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Yeah, the speeds are being reported all over the place. Might as well wait for any official FAI announcements. He REALLY accelerated for that first 20 seconds or so. That put him at about the same level as Kittingers jump already as fast as Joe ever got. The difference in the air density, or lack of at jump altitude. I'm sure that's confusing some people reporting on the event, trying to figure out how he could have jumped 20,000 feet higher and not exceeded the free fall time limit. It will be neat to see how it all shakes out. Dude definitely had what it takes to do something like that!
Dan McEntee
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I heard the free-fall distance was 119,000 feet. With the ground level in that area being between 3 and 4 thousand feet above sea level and the parachute deploying at 5,000 feet, that figure sounds pretty good.
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Gravity?
Weren't we tought that ALL objects fall to earth at the same speed?
Charles
That's true if you IGNORE air resistance, which can be done ikn theory, but not in reality.
I guess the "time in free fall" record hinges on waiting longer to open the parachute. By opening higher, Felix must have really topped the total time to desend record.
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Gravity?
Weren't we tought that ALL objects fall to earth at the same speed?
Charles
Well, technically the theory is that object fall with the same acceleration, meaning that two objects dropped from the same height will hit at the same time and with the same speed. Galileo figured that one out by rolling balls down inclined planes. He actually made two mistakes with that one, neither of which affected his results very much - one, he ignored the moment of inertia of the ball, and two, the one that applies here, he ignored air resistance AKA drag. At the speeds the ball rolled down the plane, the air did nearly nothing and the actual effect was far below his ability to measure.
In a vacuum, it works exactly as Galileo said, as proven by the experiment on Apollo 15.
For any object dropped in air, there are at least two effects that affect the acceleration depending on the mass of the object. One, the buoyancy of the object, can safely be ignored for people. It can't be ignored for the entire balloon/gondola assembly, it was released and *went the wrong way*! The other effect is aerodynamic drag. The acceleration of the object is the 1G (which also varies with altitude...) MINUS the force of drag/mass. At some speed, the drag force equals the weight, and the speed stays constant. As the air gets thicker the speed at which the two are equal goes down, so at 90,000 feet it might be 1000 fps, and at 1000 feet it's only about 150-180 feet per second.
Brett
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I watched the jump live on the Discovery Channel, and they had some telemetry figures running on the screen as he made his ascent, and when he jumped, a time clock started to time his free fall and they had a list of the records they were trying to break. He pulled the ripcord at 4:19 and 5000 feet altitude (if I remember correctly) and they had Kittinger's record for free fall right next to the clock and I think it was 4:36. Then they cut away to another shot and none of the pertinant info was seen again. I think his speed exceed 500 mph in the first 10 seconds of the jump. He was considerably higher at jump altitude than Kittinger was. I'm not going to even try to attempt the math required that you all know to figger this stuff out, but I'm just going to guess that the air at Kittinger's jump point was much more dense, and he accelerated considerably slower, and that is why his free fall time was longer. I read in a report somewhere that the 'chute was pulled at 5000 ft for safety, and I can't imagine that Kittinger had his chute open much lower than that, and a few thousand feet more of free fall would have accounted for the extra 17 seconds. At 5000 feet he should slowed to a more "normal" speed that sky divers drop at. I guess the question I'm trying to ask is the extra speed that he would have built up in the much thinner or none existant air at 180,000 ft carried him through the increasing density fast enough to eat up the altitude fast enough he couldn't exceed the free fall time? Was his pressure suit "cleaner" than Kittingers and let him fall faster at the more dense altitudes.Am I making any sense?????? I guess I better go back to work.
Type at you later,
Dan McEntee
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I'm assuming when all the official number crunching is done they will be able to tell us how long he remained at supersonic speed. I wonder if anyone heard a sonic boom? What would be interesting is a chart showing his speed at different altitudes and perhaps how long it took from bailout to reach those altitudes.
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I believe that Kittinger used a very small drogue chute on the Excelsior jumps to stabilize himself. This may account for the few seconds faster freefall by Baumgartner.