Posted on 11/02/2014 8:18:07 PM PST by BenLurkin
Early analysis suggests that a violent structural failure rather than an engine explosion may have caused the crash of Virgin Galactic LLC’s experimental rocket ship Friday, according to safety experts and one person familiar with details of the investigation.
The National Transportation Safety Board’s probe of the accident is just beginning and it could change direction, these people said. But based on video footage and preliminary data analysis, they said, investigators are focusing on aerodynamic forces that could have caused the dramatic in-flight rupture of the craft, which killed one pilot and seriously injured the other. Because some engine malfunctions can sharply increase structural loads, it is too early to rule anything out, they said.
...
SpaceShip Two’s fuel tanks and engine were recovered largely intact. The hybrid motor fueled by nitrous oxide and a plastic-based compound were found some 5 miles from where large sections of the tail first hit the ground. Sections of the fuselage, fuel tanks and cockpit were located some distance from the engine itself.
The condition and location of various pieces of the wreckage suggest there was no propulsion-system explosion before the craft starting coming apart miles above California’s Mojave Desert, according to air-safety experts who have reviewed the images.
(Excerpt) Read more at online.wsj.com ...
The posted photo seems to indicate the engine attached and receiving fuel, based on an exhaust plume evident (orange glow). One speculation is structural failure near the engine. Structural failure shifting the thrust vector could destabilize the craft.
Another article says the co-pilot initiated the early deployment. It took only two seconds for the plane to start breaking apart.
it may have been too many unknown variables at once.
i had heard this was a new engine being used. then later i read here that they were also using a new fuel this time.
perhaps the new engine could only use the new fuel, not sure, but change too many untested things at once,...
Maybe they couldn’t control the burn and they activated the feathering to slow the thing down, but it couldn’t handle the stress?
How about the pilot pulled too many G’s when he went vertical and overstressed the tail booms.
One report states it may have been that the co-pilot released the feather control while still accelerating. That would do it.
According to the following video, the NTSB is saying the feathers aren’t to be unlocked until they reach mach 1.4. They were unlocked at Mach 1.0.
For decades the aviation industry has used placards inside aircraft to remind pilots not to do something dangerous specific to the aircraft they are flying. Modern aircraft use software and other safeguards to prevent dangerous actions. I can’t believe VG didn’t use similar measures. If I had a deposit for a flight I would get it back.
http://www.usatoday.com/story/tech/2014/11/03/virgin-galactic-spacecraft-crash-pilot-ntsb/18398329/
I guess I’m not up to speed on how the feathering mechanism is supposed to work. I just assumed it was used like a brake to slow the ship down, but I’m not familiar with the speed or altitude restrictions.
“We” took a few decades to really learn how to build ships out of something other than wood.
Acting Chairman Christopher A. Hart’s Third Media Briefing on Crash of SpaceShipTwo, Mojave, Calif.
https://www.youtube.com/watch?v=vjYVhGvUSNc
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