5 ms·
Preliminary (i.e., non-record certified) telemetry: Exit altitude: 128,100 ft 39,045 m Free-fall time: 4m:20s Free-fall distance: 119,846 ft 36,
by Arjuna 14y ago
Preliminary (i.e., non-record certified) telemetry:
Exit altitude:
128,100 ft
39,045 m
Free-fall time:
4m:20s
Free-fall distance:
119,846 ft
36,529 m
Maximum velocity:
373 m/s
1,342.8 km/h
833.9 mph
Mach 1.24
- bradgessler 14y agoIs breaking the sound barrier noticeable to the sky diver?
- andysinclair 14y agoHe was just asked this at the press conference, and he replied that he felt nothing as he is in a pressurised suit (he could neither feel or hear anything during the fall).
- nikcub 14y agoNo it doesn't. The problem with the sonic boom in fighter jets and the associated forces it produces is because the control surfaces of the planes at the time weren't designed to deal with the effects from supersonic speeds[0], so they would lose control. There is no 'force' associated with breaking the sound barrier, as most would imagine Most of the forces in the freefall would have been G forces from the tumbling or spinning motion as he jumped out. [0] the tl;dr for aircraft is that as you approach and overtake mach 1, at some point the airflow at the beginning of the wing is supersonic while at the rear of the wing it is not, as you accelerate this point moves from the front of the wing to the rear. the problem is that it causes the airflow from that point to separate from the wing which results in a stall, spin, crash etc.
- jasonwatkinspdx 14y agoThis is slightly misleading. There is wave drag, which is caused by the formation of shocks. This happens when the plane/body is nearing the speed of the pressure wave it creates ahead of itself. The air no longer has sufficient time to flow around the body in a smooth (or even turbulent) way. Instead it piles up into sharp discontinuities called shocks, with very low pressure regions behind the shocks. This produces a lot of drag, several times more than that due to viscous drag alone. That's where the concept of a 'sound barrier' came from. People weren't sure what the maximum drag would be, or if we could build engines powerful enough to overcome it. Obviously we can and did. But in the case of free fall from space or near space, the air is so thin that these effects are minimal. Also his starting velocity moving through the thin air is much lower than say a reentering space craft, so the whole thing is much more mild and manageable. By the time the air gets thick enough to worry about, he'll have shed enough speed to even the slight early drag to be at a reasonable terminal velocity. (This is the same concept used by SpaceShipOne's 'shuttlecock' re-entry).
- 001sky 14y agoBut in the case of free fall from space or near space, the air is so thin that these effects are minimal. -- This is interesing, Thanks. Do we know at what altitude he hit Mach 1.0, out of curiousity?
- gort 14y agoBack of envelope calculation: A. Starting height = 39045 m B. Desired speed = 343 m/s C. Acceleration = 9.8 m/s/s D. Average speed while accelerating = 171 m/s (half of B) E. Time to reach desired speed = 35 s (B divided by C) F. Therefore distance travelled = 5985 m (D times E) G. Therefore altitude at Mach 1 = 33060 m, give or take the small amount of drag. Edit: Meh, I see from the video that he didn't accelerate as fast as this, I guess the drag was significant after all. Even a small amount of gas will move you if it's coming at you at significant speeds...
- shasta 14y agoI think he meant altitude at which he was slowed back to mach 1.0.
- lusr 14y agoWhat it (kind of, the focal length of the camera notwithstanding) looked like from up there: http://twitter.com/57UN/status/257547773975601152/photo/1/large http://twitter.com/57UN/status/257547773975601152/photo/1/la...
- deleted 14y ago[deleted]
- kahawe 14y ago> Mach 1.24 How appropriate - the speed of an Austrian skydiver measured in a unit named after an Austrian physicist!