Federal safety investigators say the crash of a Virgin Galactic spaceship last year was caused by a catastrophic structural failure triggered when the co-pilot unlocked the craft's braking system early.
The National Transportation Safety Board investigators say the resulting aerodynamic forces caused the brakes to actually be applied without any further action by the crew.
Investigators are also telling the board that no safeguards were built into system to overcome the error of the co-pilot.
The NTSB began its hearing Tuesday into what caused the spaceship to break apart over the Mojave Desert during a test flight 10 months ago. The accident killed the co-pilot and seriously injured the pilot.
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