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Aviation Week reported it back in May. So, yes. I'll keep an eye out for the accident report. http://m.aviationweek.com/space/new-fuel-boost-spaceshiptwo http:

by termain 12y ago

Aviation Week reported it back in May. So, yes. I'll keep an eye out for the accident report. http://m.aviationweek.com/space/new-fuel-boost-spaceshiptwo http://m.aviationweek.com/space/new-fuel-boost-spaceshiptwo

marze 12y ago
Well you could be right, but it is very hard to imagine that being true since the plastic hybrid has only been tested once on the ground. Doing a flight test so soon would be totally insane. In any case, the disaster was undoubtably a result of inadequate ground testing. Problems like these are almost always the result of management pushing things faster than the engineering progress warrants.
- termain 12y ago
  I think it's also possible that a bad fuel grain slipped through whatever QA process they had. You might count that as insufficient ground testing, though. "Problems like these are almost always the result of management pushing things faster than the engineering progress warrants." Coincidentally, we were talking about such an instance today at work, the Conestoga 1620. As relayed to me, the "low frequency noise" mentioned in the wikipedia post was a low frequency structural mode that was missed because management didn't want to pay for a high enough fidelity finite element analysis. https://en.wikipedia.org/wiki/Conestoga_%28rocket%29 https://en.wikipedia.org/wiki/Conestoga_%28rocket%29
- Steko 12y ago
  Virgin has to get Brandon to space this year or their funding is subject to considerable clawback.
  - lotsofmangos 12y ago
    Do they still get to keep the funding if he returns?
- Steko 12y ago
  Virgin has to get Brandon to space this year or their funding is subject to considerable clawback.
- chris_wot 12y ago
  You don't know what the problem was.
- lotsofmangos 12y ago
  Officials decided this spring to modify the space plane’s rocket motor to use a different type of fuel. Instead of burning a rubber-based fuel mix known as HTPB used on SpaceShipOne and SpaceShipTwo’s initial test flights, Virgin Galactic selected a new propellant grain known as polyamide which officials said offered improved performance. “This was a new fuel formulation that had been proven and tested on the ground many times,” Mickey said in a press conference. http://spaceflightnow.com/2014/10/31/virgin-galactics-spaceshiptwo-suffers-anomaly-during-test-flight/ http://spaceflightnow.com/2014/10/31/virgin-galactics-spaces...
  - marze 12y ago
    Let us hope for Virgin's sake that "many times" doesn't mean six times for ten seconds each. I have heard of one long duration test on the plastic fuel reported by the "Virgin watchers" in Mojave, so unless they are doing long duration tests somewhere else it doesn't seem like much. Rocket engine testing is extremely noisy so long duration tests are quite noticeable.

by termain 12y ago

marze 12y ago

Well you could be right, but it is very hard to imagine that being true since the plastic hybrid has only been tested once on the ground. Doing a flight test so soon would be totally insane. In any case, the disaster was undoubtably a result of inadequate ground testing. Problems like these are almost always the result of management pushing things faster than the engineering progress warrants.

termain 12y ago
I think it's also possible that a bad fuel grain slipped through whatever QA process they had. You might count that as insufficient ground testing, though. "Problems like these are almost always the result of management pushing things faster than the engineering progress warrants." Coincidentally, we were talking about such an instance today at work, the Conestoga 1620. As relayed to me, the "low frequency noise" mentioned in the wikipedia post was a low frequency structural mode that was missed because management didn't want to pay for a high enough fidelity finite element analysis. https://en.wikipedia.org/wiki/Conestoga_%28rocket%29 https://en.wikipedia.org/wiki/Conestoga_%28rocket%29
Steko 12y ago
Virgin has to get Brandon to space this year or their funding is subject to considerable clawback.
- lotsofmangos 12y ago
  Do they still get to keep the funding if he returns?
Steko 12y ago
Virgin has to get Brandon to space this year or their funding is subject to considerable clawback.
chris_wot 12y ago
You don't know what the problem was.
lotsofmangos 12y ago
Officials decided this spring to modify the space plane’s rocket motor to use a different type of fuel. Instead of burning a rubber-based fuel mix known as HTPB used on SpaceShipOne and SpaceShipTwo’s initial test flights, Virgin Galactic selected a new propellant grain known as polyamide which officials said offered improved performance. “This was a new fuel formulation that had been proven and tested on the ground many times,” Mickey said in a press conference. http://spaceflightnow.com/2014/10/31/virgin-galactics-spaceshiptwo-suffers-anomaly-during-test-flight/ http://spaceflightnow.com/2014/10/31/virgin-galactics-spaces...
- marze 12y ago
  Let us hope for Virgin's sake that "many times" doesn't mean six times for ten seconds each. I have heard of one long duration test on the plastic fuel reported by the "Virgin watchers" in Mojave, so unless they are doing long duration tests somewhere else it doesn't seem like much. Rocket engine testing is extremely noisy so long duration tests are quite noticeable.