Credit: AP/BBC
Having seen the images above, the recent Virgin Galactic accident was widely interpreted as an engine explosion. However, a US National Transport Safety Board (NTSB) representative has said that premature deployment of the feather capability was the cause of the accident.
National Transport Safety Board representative explains feathering
Spaceship 2 feathering in testing
Feathering is the solution Virgin Galactic has adopted for the problem of re-entry into the Earth's atmosphere*. It was designed to be deployed at 350,000 feet. By decelerating the SpaceShip at extreme altitude, in a thin atmosphere, extreme heat build-up, as experienced by NASA & other space vehicles (with occasional catastrophic results), is avoided. Richard Branson & others have referred to this as, "carefree re-entry"**.
In the recent accident, feathering was deployed at a relatively low altitude (40,000 feet), where the atmosphere is much thicker, at a velocity greater than Mach 1. Forces generated were much greater than SpaceShip 2 would normally encounter. Apparently these forces destroyed the aircraft.
In the image at the top of this post, the right hand pane appears to show a ball of flame at the top right, with pieces of SpaceShip 2 & a debris trail below & to the left. The apparent ball of flame was widely interpreted as an explosion in progress.
In light of the NTSB investigation, the image may be interpreted as the feathered space vehicle with the rocket engine pointing straight up. I.e. away from the camera. In this case, the apparent, “ball of flame”, would be the rocket exhaust pointing straight down toward the camera.
http://www.abc.net.au/news/2014-11-04/no-explosion-behind-virgin-galactic-crash-branson/5864110
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* Virgin Galactic technology originated in Burt Rutan's Scaled Composites:
http://www.businessinsider.com.au/5-things-you-didnt-know-about-the-company-testing-virgin-galactics-spaceshiptwo-2014-11
** Care-free re-entry:
http://www.typgalactic.com/english/faq.html / Virgin Galactic crash Richard Branson angered damaging innuendo feathering function deployed early Sir Richard Branson British billionaire founder Virgin Galactic self-proclaimed experts explosion crash spacecraft last week Mojave Desert California kill 39 year old pilot Michael Alsbury injure 43 year old Peter Siebold no explosion crash oxidiser oxidant fuel tanks engine irresponsible innuendo damaging sensationalist press reports incredibly hurtful journalists push on passenger travel space programme fly members of the public fly myself and family member investigation one year space safety expert warnings /
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