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A comment on SpaceshipTwo crashes shortly after Mojave test flight. Parent comment

Re:SpaceshipTwo crashes shortly after Mojave test flight by termain on Friday October 31, 2014 @07:11PM (#8541554)
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

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Re:SpaceshipTwo crashes shortly after Mojave test flight by marze on Friday October 31, 2014 @09:32PM (#8541918)
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.

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Re:SpaceshipTwo crashes shortly after Mojave test flight by termain on Friday October 31, 2014 @10:06PM (#8541967)
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

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Re:SpaceshipTwo crashes shortly after Mojave test flight by Steko on Saturday November 01, 2014 @12:51AM (#8542226)
Virgin has to get Brandon to space this year or their funding is subject to considerable clawback.
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Re:SpaceshipTwo crashes shortly after Mojave test flight by lotsofmangos on Saturday November 01, 2014 @06:01PM (#8544789)
Do they still get to keep the funding if he returns?
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Re:SpaceshipTwo crashes shortly after Mojave test flight by lotsofmangos on Saturday November 01, 2014 @09:03AM (#8542888)
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-spaces...

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Re:SpaceshipTwo crashes shortly after Mojave test flight by marze on Saturday November 01, 2014 @03:17PM (#8544244)
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.

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Re:SpaceshipTwo crashes shortly after Mojave test flight by chris_wot on Saturday November 01, 2014 @05:29AM (#8542579)
You don't know what the problem was.
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