Mitch Cronin Posted May 26, 2008 Share Posted May 26, 2008 Some people might say this guy's got a lot of courage.... I know better. I'm crazy too, but I'm just not that kind of crazy. I like guys like this. http://www.legrandsaut.org/index.php?lang=eng# --forgot to mention... Yesterday it didn't happen for weather... current plan is he's doing it today.[butyouallknewthat] Link to comment Share on other sites More sharing options...
Moon The Loon Posted May 26, 2008 Share Posted May 26, 2008 Some people might say this guy's got a lot of courage.... I know better. I'm crazy too, but I'm just not that kind of crazy. I like guys like this. http://www.legrandsaut.org/index.php?lang=eng# --forgot to mention... Yesterday it didn't happen for weather... current plan is he's doing it today.[butyouallknewthat] Mach 1.4 or even 1.0. Yeah, right. At -65 C, the speed of sound is 648 mph. Terminal velocity, even in rarifed air can't possibly be that high. Then there is the transonic drag. I think the press has been fed a wagon-load of horse patootie. Link to comment Share on other sites More sharing options...
Tango Niner Posted May 26, 2008 Share Posted May 26, 2008 Kittinger (1960), jumping from 102,800 feet, apparently reached 614 mph. I did a bit of surfing on the subject and didn't find any dispute of this figure (although there were higher numbers claimed, such as 714 mph, which were summarily rejected) I think a jump from 130,000 feet has at least a reasonable chance of coming close to the sound barrier, early in the descent. Hopefully Fournier's got some good speed measuring equipment with him. I'm thinking some kind of GPS-based system, perhaps? T9 Link to comment Share on other sites More sharing options...
Kip Powick Posted May 26, 2008 Share Posted May 26, 2008 Interesting stuff here............ http://hypertextbook.com/facts/JianHuang.shtml Link to comment Share on other sites More sharing options...
Kip Powick Posted May 27, 2008 Share Posted May 27, 2008 NORTH BATTLEFORD, SASK. — French adventurer Michel Fournier's quest to set a world skydiving record may have come to an end after his $200,000 helium balloon escaped and floated into space without him attached on Tuesday. A little Problem----Globe and Mail Link to comment Share on other sites More sharing options...
handyman Posted May 27, 2008 Share Posted May 27, 2008 Mach 1.4 or even 1.0. Yeah, right. At -65 C, the speed of sound is 648 mph. Terminal velocity, even in rarifed air can't possibly be that high. Then there is the transonic drag. I think the press has been fed a wagon-load of horse patootie. Explain the high speed entry of the shuttle then? No engines on it and it sees over 17,000MPH! You go high enough and those speeds are very possible. Link to comment Share on other sites More sharing options...
Mitch Cronin Posted May 27, 2008 Author Share Posted May 27, 2008 So the question is whether gravitational acceleration alone can get a falling man to Mach 1.4 in the vertical distance he'll have, before drag will increase enough to stop his acceleration... without knowing how altitude varies gravitational acceleration - you'd have to think there must be some altitude from which that could be achieved?... 130,000' is pretty darned "rarified" isn't it? Heck, if you could find a way to get it there, I bet you could get a Seabee supersonic up there! Link to comment Share on other sites More sharing options...
Mitch Cronin Posted May 27, 2008 Author Share Posted May 27, 2008 Current status: Translation: French » English Le ballon à été retrouvé dans les plaines à 40km de la zone de lancement. Les techniciens étudient actuellement le dysfonctionnement. Une conférence de presse sera donnée dès les premières conclusions. The ball was found in the plains 40km of the launch area. The technicians are currently studying the malfunction. A press conference will be given an early conclusions. Link to comment Share on other sites More sharing options...
Kip Powick Posted May 27, 2008 Share Posted May 27, 2008 Current status: Translation: French » English Le ballon à été retrouvé dans les plaines à 40km de la zone de lancement. Les techniciens étudient actuellement le dysfonctionnement. Une conférence de presse sera donnée dès les premières conclusions. The ball was found in the plains 40km of the launch area. The technicians are currently studying the malfunction. A press conference will be given an early conclusions. The balloon was found in the.... Link to comment Share on other sites More sharing options...
Moon The Loon Posted May 27, 2008 Share Posted May 27, 2008 Explain the high speed entry of the shuttle then? No engines on it and it sees over 17,000MPH! The Shuttle is decelerating from a "groundspeed" in excess of 17,000 miles per hour, whatever orbital velocity was. This human fly must accelerate from "zero" to terminal velocity in rarefied air. As he gets "up to speed" he will then be entering thicker air reducing his potential maximum speed. Transonic drag would probably kill him even if he succeeded in getting that far. Link to comment Share on other sites More sharing options...
Tango Niner Posted May 27, 2008 Share Posted May 27, 2008 It's of course true that his terminal velocity will decrease as he descends into the thicker air. The question is: how fast will it be when he FIRST reaches it? (way up high)... it could very well be in excess of Mach 1. There's no mathematical reason for it not to be, if he gets high enough before he jumps. Appears to be a moot point anyway... from the looks of things, Mr. Fournier won't be flying for a while yet. Link to comment Share on other sites More sharing options...
Thebean Posted May 27, 2008 Share Posted May 27, 2008 It's of course true that his terminal velocity will decrease as he descends into the thicker air. The question is: how fast will it be when he FIRST reaches it? (way up high)... it could very well be in excess of Mach 1. There's no mathematical reason for it not to be, if he gets high enough before he jumps. Appears to be a moot point anyway... from the looks of things, Mr. Fournier won't be flying for a while yet. I am reminded of another balloon adventurer who's family pleaded, threatened and begged him not to embark on another highly publicized and risky adventure. Not going would have tarnished a well groomed reputation. The issue was resolved when the balloon "escaped" when it was being inflated. All's well that ends well. Link to comment Share on other sites More sharing options...
Specs Posted May 27, 2008 Share Posted May 27, 2008 All's well that ends well. Ballons are like TRIX cereal - only for kids - An update on the balloning priest Brazil ends search for ballooning priest Tuesday, 29 April, 2008 text Brazil's navy has ended its search for a priest who vanished more than a week ago while floating over the Atlantic with a cluster of party balloons. Father Adelir Antonio de Carli has been missing since April 20, shortly after he lifted off from the southern port city of Paranagua strapped to 1,000 helium-filled balloons. Navy spokeswoman Lieutenant Catia Sandri said the hunt, conducted with one helicopter and two boats, was called off over the weekend because no sign of the priest was found after 135 hours of searching. She said several private fishing boats were still looking for the Catholic priest, but said chances of finding de Carli alive in the ocean are "very remote". The air force ended its four-day search for the priest on Thursday after its planes covered more than 5,000 square kilometres of land and sea. Fire department rescue teams continued looking for the 41-year-old priest in densely forested coastal mountains, said Deputy Fire Commander Paulo Eduardo Neves. The priest had been trying to raise money to build a rest stop and worship centre for truckers. Link to comment Share on other sites More sharing options...
Guest rattler Posted May 27, 2008 Share Posted May 27, 2008 Regarding the velocity you might attain. Here is what one pioneer achieved. Captain Kittinger was then assigned to the Aerospace Medical Research Laboratories at Wright-Patterson AFB in Dayton, Ohio. For Project Excelsior (meaning "ever upward", a name given to the project by Colonel Stapp), as part of research into high altitude bailout, he made a series of three parachute jumps wearing a pressurized suit, from a helium balloon with an open gondola. The first, from 76,400 feet (23,287 m) in November, 1959 was a near tragedy when an equipment malfunction caused him to lose consciousness, but the automatic parachute saved him (he went into a flat spin at a rotational velocity of 120 rpm; the g-force at his extremities was calculated to be over 22 times that of gravity, setting another record). Three weeks later he jumped again from 74,700 feet (22,769 m). For that return jump Kittinger was awarded the Leo Stevens parachute medal. On August 16, 1960 he made the final jump from the Excelsior III at 102,800 feet (31,330 m). Towing a small drogue chute for stabilization, he fell for 4 minutes and 36 seconds reaching a maximum speed of 614 mph (988 km/h or 274 m/s) before opening his parachute at 18,000 feet (5,500 m). Pressurization for his right glove malfunctioned during the ascent, and his right hand swelled to twice its normal size.[2] He set records for highest balloon ascent, highest parachute jump, longest drogue-fall (14 min), and fastest speed by a human through the atmosphere[3]. The jumps were made in a "rocking-chair" position, descending on his back, rather than the usual arch familiar to skydivers, because he was wearing a 60-lb "kit" on his behind and his pressure suit naturally formed that shape when inflated, a shape appropriate for sitting in an airplane cockpit. Another article shows a higher speed. After being assigned to the Aerospace Medical Research Laboratories, Wright-Patterson AFB, Dayton, Ohio, Kittinger was appointed Test Director of "Project Excelsior," investigating escape from high altitude. During this project there were three high altitude jumps accomplished from a balloon-supported gondola--from 76,400 on November 16, 1958, from 74,700 25 days later, and on August 16, 1960, from 102,800 feet, the highest altitude from which man has jumped. In freefall for 4.5 minutes at speeds up to 714 mph and temperatures as low as -94 degrees Fahrenheit, Kittinger opened his parachute at 18,000 feet. In addition to the altitude record, he set records for longest freefall and fastest speed by a man (without an aircraft!) For work accomplished during the project, Captain Kittinger was awarded the C.B. Harmon Trophy, which was presented by President Eisenhower on October 3, 1960, an oak leaf cluster to the Distinguished Flying Cross, the J.J. Jeffries Award, the Leo Stevens Parachute Medal and the Wingfoot Lighter-Than-Air Society Achievement Award. Link to comment Share on other sites More sharing options...
Moon The Loon Posted May 27, 2008 Share Posted May 27, 2008 It looks like some people don't understand two things: 1. The local speed of sound varies directly with the ambient temperature. Lower temperature = lower speed of sound; higher temperature = higher speed of sound. At -65 (my example above, using a typical troposphere temperature), the speed of sound is 648 mph. At -45 it's 677. At -25 it's 706, at -15 it's 720, at -5 it's 734. Mach 1.4 using these numbers are 40% higher than these numbers. 648 x 1.4 = 908 mph. 734 x 1.4 = 1028 mph. 2. Transonic aerodynamics. Airplanes have critical mach numbers so that no airflow over any part of the airframe accelerates to greater than Macn 1.0. For instance, the B767 has a Mmo (not necessarily a Mcrit) of 0.86. One reason being the incredible increase in drag that occurs during the "punch" through this "barrier". Another reason being the reversal of Bernoulli's principle: as airflow goes through a venturi, its pressure increases and its velocity decreases. Anyway, my original response to this story basically labelled this guy's claim as Poppycock. The latest "scientific" method demonstrated by this clown's team would seem to back that up. Link to comment Share on other sites More sharing options...
Moon The Loon Posted May 27, 2008 Share Posted May 27, 2008 Hiya Rich: I posted over top of you and didn't see yours prior to submitting mine. Regardless - nobody has alluded to how they were going to measure his freefall airspeed. Perhaps something as simple as a local p-s system hooked to a computer? Or a GPS speed corrected to airspeed, then Mach? If he becomes supersonic, will he create a Boom? A sonic boom is a good indication of the amount of energy created by a 3D shape exceeding the speed of sound in the air. I assume your M1.3 at 56,000' was in a dive? Or was it on after-burner in level flight? I still can't believe this guy got funding to do this stunt! Link to comment Share on other sites More sharing options...
Kip Powick Posted May 27, 2008 Share Posted May 27, 2008 Never say "never" !!! Moon...did you actually go and read this link and check out all the formulae??? http://hypertextbook.com/facts/JianHuang.shtml Seems to me that mach 1+ is possible. Another point...if it can not be proven that it is possible, why would the three individuals get financial backing........Ok..OK..Stearns ran out of money and "changed her mind", and the Australian disappeared...but they did get the backing. Kinda curious don't cha think....but maybe this last guy had real second thoughts and "let the balloon go"...is possible...yes??.......just like the phoney reason for letting the recent MP "go"...yes ????? Anyhooooo standing by for the great plunge !!! Link to comment Share on other sites More sharing options...
Moon The Loon Posted May 27, 2008 Share Posted May 27, 2008 Moon...did you actually go and read this link and check out all the formulae??? http://hypertextbook.com/facts/JianHuang.shtml C'mon Kip: Why would I let facts interfere with my way of reasoning? I will do that however. Just because it is the right thing to do I still say "M1.4, Bollocks!" Link to comment Share on other sites More sharing options...
Moon The Loon Posted May 27, 2008 Share Posted May 27, 2008 ...and another thing, for those referring to the 714 number, and I quote: "Given this, why then do so many sources report that Kittinger exceeded the speed of sound? One possible answer comes from the relatively obvious similarity between Kittinger's self-reported value of 614 mph and the most frequently misreported value of 714 mph (319 m/s). Somebody must have heard 614 but entered 714 accidentally into some officious document (like an encyclopedia). Some other people read the error and then reported it as fact. Many more people read these "facts" and suddenly nearly everyone was remembering the day Captain Kittinger broke the sound barrier. Another factoid is born." So yeah, I have now read the article. Nothing in it allows for supersonic freefall! Link to comment Share on other sites More sharing options...
Kip Powick Posted May 28, 2008 Share Posted May 28, 2008 So yeah, I have now read the article. Nothing in it allows for supersonic freefall! You and your "speed reading" The author states it is possible.....(M1.3) ......and hopefully we will see if it is................. and put this discussion to bed !!! Link to comment Share on other sites More sharing options...
boestar Posted May 28, 2008 Share Posted May 28, 2008 He!! if a DC8 can go supersonic from 35000 feet anything is possible. Link to comment Share on other sites More sharing options...
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