piisfish 140 #101 October 15, 2012 Quote Yeah not that it diminishes the jump in ANY way but curious as to why freefall record stands??what do you mean ? time ? Kittinger's jump was with a drogue. Felix was droguelessscissors beat paper, paper beat rock, rock beat wingsuit - KarlM Quote Share this post Link to post Share on other sites
cocheese 0 #102 October 15, 2012 So the wingsuit world record for freefall time... what's up with that? I thought that was the longest free fall. Quote Share this post Link to post Share on other sites
piisfish 140 #103 October 15, 2012 Quote So the wingsuit world record for freefall time... what's up with that? I thought that was the longest free fall.for me there is a difference between "freefall" "droguefall" "wingsuitfall" all records are good and I admire everybody. It is just not the same category.scissors beat paper, paper beat rock, rock beat wingsuit - KarlM Quote Share this post Link to post Share on other sites
airdvr 210 #104 October 15, 2012 Question that nags at me. Although he set a freefall speed record I don't believe he technically 'broke the speed of sound'. Not that it takes anything away from this accomplishment.Please don't dent the planet. Destinations by Roxanne Quote Share this post Link to post Share on other sites
wolfriverjoe 1,523 #105 October 15, 2012 Quote Question that nags at me. Although he set a freefall speed record I don't believe he technically 'broke the speed of sound'. Not that it takes anything away from this accomplishment. I read that he hit Mach 1.24. Well above the speed of sound. Rmember that the speed of sound is slower at higher altitudes."There are NO situations which do not call for a French Maid outfit." Lucky McSwervy "~ya don't GET old by being weak & stupid!" - Airtwardo Quote Share this post Link to post Share on other sites
airdvr 210 #106 October 15, 2012 Hmmm....I thought it would be much higher.Please don't dent the planet. Destinations by Roxanne Quote Share this post Link to post Share on other sites
wolfriverjoe 1,523 #107 October 15, 2012 Quote Hmmm....I thought it would be much higher. Actually, so did I. According to Wiki, in dry air at 68F, Mach 1 is 768 mph. Felix reprtedly hit 833 mph. http://en.wikipedia.org/wiki/Speed_of_sound Far more math and physics than I want to go into on a Monday. I'm sure Professor Kallend could explain it far, far better than I."There are NO situations which do not call for a French Maid outfit." Lucky McSwervy "~ya don't GET old by being weak & stupid!" - Airtwardo Quote Share this post Link to post Share on other sites
jumpwally 0 #108 October 15, 2012 Thats surprising to me....was there a competition amongst the canopy guys ? I thought PD would have been elbowing their way into this event...smile, be nice, enjoy life FB # - 1083 Quote Share this post Link to post Share on other sites
linebckr83 3 #109 October 15, 2012 The speed of sound is directly proportional to temperature. There are 3 variables in the equation to find the speed...2 are constants depending on the state of the fluid (i.e. air) and the third is temperature. So, obviously, as temperature drops the speed of sound drops. That's for an ideal gas but it does explain why the speed of sound decreases."Are you coming to the party? Oh I'm coming, but I won't be there!" Flying Hellfish #828 Dudist #52 Quote Share this post Link to post Share on other sites
waveoff5500 0 #110 October 15, 2012 think about the distance between the molecules as you go up in altitude. up at 120,000 plus ft there is very little air density. so the sound waves have farther to travel between molecules. at regular pressures the molecules are very close together so the waves can travel between more quickly."its just a normal day at the dropzone until its not" 1653 Quote Share this post Link to post Share on other sites
JohnMitchell 16 #111 October 15, 2012 Quote think about the distance between the molecules as you go up in altitude. up at 120,000 plus ft there is very little air density. so the sound waves have farther to travel between molecules. at regular pressures the molecules are very close together so the waves can travel between more quickly. The poster above you is correct. The speed of sound is proportional to temperature, not density, a common misconception. Indicated airspeed IS proportional to density. That's why the U-2 is so tricky to fly at high altitude. It's flying just above its stall speed (IAS) and just below its critical mach speed. The two speeds converge to form a "coffin corner." Quote Share this post Link to post Share on other sites
muff528 3 #112 October 15, 2012 Temperature is the main determinate for the speed of sound but that was mostly irrelevant in Felix's breaking of the barrier. His speed was well above Mach 1 even for more "familiar" atmospheric temps. The extreme low density played the major role in allowing him to exceed Mach 1 at high altitudes by effectively increasing his terminal velocity. (Do we know if he even actually achieved terminal velocity during the supersonic portion of the descent? Is that even possible?) Quote Share this post Link to post Share on other sites
kallend 2,067 #113 October 15, 2012 Quote Quote Hmmm....I thought it would be much higher. Actually, so did I. According to Wiki, in dry air at 68F, Mach 1 is 768 mph. Felix reprtedly hit 833 mph. http://en.wikipedia.org/wiki/Speed_of_sound Far more math and physics than I want to go into on a Monday. I'm sure Professor Kallend could explain it far, far better than I. Speed of sound varies according to temperature. Colder air, speed of sound decreases. For the geeks, in dry air (as found at altitude): (speed of sound in m/sec) = 20.05*sqrt(T) T = temperature in Kelvins.... The only sure way to survive a canopy collision is not to have one. Quote Share this post Link to post Share on other sites
aradisc 0 #114 October 15, 2012 Quote (Do we know if he even actually achieved terminal velocity during the supersonic portion of the descent? Is that even possible?) His terminal velocity did not actually increase (It's not a variable, it's fixed for a given body shape and orientation). He was constantly accelerating at 9.8m/s^2 (actual "free fall", FWIW) until he hit thick enough air to slow him down. (60,000 ft ?) Then, he was actually going faster than what the terminal velocity would be if he had experienced constant air resistance in a fall to that point. Wiki says, in clearer words than mine, "An object moving downward with greater than terminal velocity (for example because it was thrown downwards or it fell from a thinner part of the atmosphere or it changed shape) will slow down until it reaches terminal velocity." It is actually possible that he did not reach terminal velocity, but we don't know that yet. Quote Share this post Link to post Share on other sites
airdvr 210 #115 October 15, 2012 Quote Quote Quote Hmmm....I thought it would be much higher. Actually, so did I. According to Wiki, in dry air at 68F, Mach 1 is 768 mph. Felix reprtedly hit 833 mph. http://en.wikipedia.org/wiki/Speed_of_sound Far more math and physics than I want to go into on a Monday. I'm sure Professor Kallend could explain it far, far better than I. Speed of sound varies according to temperature. Colder air, speed of sound decreases. For the geeks, in dry air (as found at altitude): (speed of sound in m/sec) = 20.05*sqrt(T) T = temperature in Kelvins. If we had been able to be present at that altitude would there have been a sonic boom?Please don't dent the planet. Destinations by Roxanne Quote Share this post Link to post Share on other sites
kallend 2,067 #116 October 15, 2012 Quote The speed of sound is directly proportional to temperature. . It's directly proportional to the square root of temperature in K.... The only sure way to survive a canopy collision is not to have one. Quote Share this post Link to post Share on other sites
linebckr83 3 #117 October 15, 2012 Quote Temperature is the main determinate for the speed of sound but that was mostly irrelevant in Felix's breaking of the barrier. His speed was well above Mach 1 even for more "familiar" atmospheric temps. The extreme low density played the major role in allowing him to exceed Mach 1 at high altitudes by effectively increasing his terminal velocity. (Do we know if he even actually achieved terminal velocity during the supersonic portion of the descent? Is that even possible?) That's a good question. During the live feed, you can see his speed continually increasing while in the delta position, then top out and decrease while he was attempting to fix the flat spin. I wonder if it would have continued to speed up if he didn't need to fix that spin."Are you coming to the party? Oh I'm coming, but I won't be there!" Flying Hellfish #828 Dudist #52 Quote Share this post Link to post Share on other sites
kallend 2,067 #118 October 15, 2012 Quote Quote Quote Quote Hmmm....I thought it would be much higher. Actually, so did I. According to Wiki, in dry air at 68F, Mach 1 is 768 mph. Felix reprtedly hit 833 mph. http://en.wikipedia.org/wiki/Speed_of_sound Far more math and physics than I want to go into on a Monday. I'm sure Professor Kallend could explain it far, far better than I. Speed of sound varies according to temperature. Colder air, speed of sound decreases. For the geeks, in dry air (as found at altitude): (speed of sound in m/sec) = 20.05*sqrt(T) T = temperature in Kelvins. If we had been able to be present at that altitude would there have been a sonic boom? There would certainly be a shock wave. Whether strong enough to "hear" I have no idea. I'd like to know what the instruments in his suit recorded.... The only sure way to survive a canopy collision is not to have one. Quote Share this post Link to post Share on other sites
linebckr83 3 #119 October 15, 2012 Quote Quote The speed of sound is directly proportional to temperature. . It's directly proportional to the square root of temperature in K. Well yes, the square root of gamma*R*T is what I was taught. I was saying directly (as opposed to inversely) to explain why it decreases at higher altitudes."Are you coming to the party? Oh I'm coming, but I won't be there!" Flying Hellfish #828 Dudist #52 Quote Share this post Link to post Share on other sites
460 0 #120 October 15, 2012 The ground personnel heard a sonic boom.Looks like a death sandwich without the bread - Steve Deadman Morrell, BASE 174 Quote Share this post Link to post Share on other sites
muff528 3 #121 October 15, 2012 Quote Quote (Do we know if he even actually achieved terminal velocity during the supersonic portion of the descent? Is that even possible?) His terminal velocity did not actually increase (It's not a variable, it's fixed for a given body shape and orientation). He was constantly accelerating at 9.8m/s^2 (actual "free fall", FWIW) until he hit thick enough air to slow him down. (60,000 ft ?) Then, he was actually going faster than what the terminal velocity would be if he had experienced constant air resistance in a fall to that point. Wiki says, in clearer words than mine, "An object moving downward with greater than terminal velocity (for example because it was thrown downwards or it fell from a thinner part of the atmosphere or it changed shape) will slow down until it reaches terminal velocity." It is actually possible that he did not reach terminal velocity, but we don't know that yet. Yes, I probably shouldn't have used the term "terminal velocity" since that has a specific meaning. Probably should have said something like "maximum attainable velocity for a given configuration and density" or some such. Quote Share this post Link to post Share on other sites
1969912 0 #122 October 15, 2012 http://i.imgur.com/E00nl.gif "Once we got to the point where twenty/something's needed a place on the corner that changed the oil in their cars we were doomed . . ." -NickDG Quote Share this post Link to post Share on other sites
ryoder 1,590 #123 October 15, 2012 Quote The ground personnel heard a sonic boom. Color me skeptical. The shock travels at a right angle from the path of travel. That would be horizontal, parallel to the surface of the earth, in this case."There are only three things of value: younger women, faster airplanes, and bigger crocodiles" - Arthur Jones. Quote Share this post Link to post Share on other sites
FallingTiger 0 #124 October 15, 2012 A Reddit user put together a nice video of the highlights of the jump, including some chest cam footage. Here's the link (at least until YouTube decides to take it down http://www.youtube.com/watch?v=ES02mWIJ2Tk&feature=youtu.be"I'm gonna die young, but I'm gonna be a legend." -Ricky Clinton Quote Share this post Link to post Share on other sites
muff528 3 #125 October 15, 2012 Quote http://i.imgur.com/E00nl.gif If they expect to get a good score they'll need to tighten that exit up. Quote Share this post Link to post Share on other sites
