Virgin Galactic's SpaceShipTwo Lost in Test Flight; One Pilot Reported Dead

  • #31
dlgoff said:
Especially the ones who have paid up to $250k for their tickets.

Maybe in case of everything ending in a fireball passengers should get the money back?And more seriously: I would be careful with drawing conclusion from number of accidents in testing phase and in phase of actual application.
 
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  • #32
I always thought the design looked fragile, but then I reflect back on looking out of a commercial plane and watch the wings separate into 4 or 5 linked together sections that seem impossible to be supporting the craft:nb), helps me appreciate materials and engineers :)
 
  • #33
Why don't the efforts of government space agencies earn accusations of hubris after accidents? Challenger? Columbia? NASA put the aging John Glen aboard the Shuttle for PR. Who paid for his ticket? Me. You.
 
  • #34
The space shuttle had a better success rate (and going to orbit is much harder than going to space). And they still got a lot of criticism.
 
  • #35
Virgin Galactic crash: Descent system 'deployed early'
http://www.bbc.com/news/world-us-canada-29876154

I'm a bit puzzled by the comment that the descent system "was deployed prior to Mach 1.4". It would seem the aerodynamic forces would be greater as velocity increases, but I can imagine that the transonic region would experience a fair amount of buffeting.

I think it more likely it is a matter of altitude and air density, and perhaps with a more powerful engine, they got to higher speeds earlier, i.e., at lower altitude, which would produce greater aerodynamic forces, due to greater air density. Remember that the space shuttle has to throttle down briefly to mitigate the aerodynamic forces until it gets to high enough altitude, where the air density is less.

It would seem, they either deployed the descent system prematurely, which is a critical error, or the craft design couldn't handle the higher forces.
 
  • #36
Astronuc said:
I'm a bit puzzled by the comment that the descent system "was deployed prior to Mach 1.4". It would seem the aerodynamic forces would be greater as velocity increases, but I can imagine that the transonic region would experience a fair amount of buffeting.
That sounds basically right to me, with one minor difference. In fact, I'm having trouble understanding why anything that interferes with airflow would be ever be deployed above 0.8 or maybe 0.9 Mach. Transonic shock was why everyone but a few dreamers believed that no object could ever exceed the speed of sound; once past it the ride smooths out. It's less decelerating through than accelerating, but still present. I'd expect such deployment to be roughly equivalent to an Airbus 380 or something similar dropping the gear and flaps and popping the spoilers while still at cruise speed. Survivable, perhaps, but hardly advisable.
 
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  • #37
Now that more details have emerged, it seems even more amazing that Pete Siebold survived. There was no ejector seat as such, and the cockpit escape hatch was apparently still in place. They didn't have pressure suits.

Apparently (according to an anonymous source from Scaled Composites quoted in the Washington Post) he found himself still strapped to his seat but outside the cockpit, gave a "thumbs-up" to a chase plane, and then unstrapped himself and deployed his parachute, but injured his shoulder in the process. (I'd guess that would be because his terminal velocity falling in the seat would be greater than the normal free fall speed, and perhaps he still had some of that excess speed when he deployed the parachute).

Here's the relevant article: http://www.washingtonpost.com/news/...es-from-crash-site-human-error-not-ruled-out/
 
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  • #38
oo)
That's definitely something that I'd put down to good luck more than good planning.
 
  • #39
Danger said:
oo)
That's definitely something that I'd put down to good luck more than good planning.

I must admit I was originally surprised that anyone survived and assumed that this was the result of some impressive advanced safety features. I now assume it was more likely to be the result of his seat breaking loose and falling out of the back of the fuselage, after which he was still very lucky to have succeeded in unstrapping himself and deploying his parachute.
 
  • #40
Jonathan Scott said:
after which he was still very lucky to have succeeded in unstrapping himself and deploying his parachute.
Doubly amazing in light of how many fighter pilots have been killed because their purpose-built ejection seats smacked them into a tailfin or other piece of the bird.