A co-pilot mistake caused Virgin Galactic’s space plane crash last year in an act of human error that its designer Scaled Composites failed to anticipate, National Transportation Safety Board (NTSB) investigators have said.
A co-pilot mistake caused Virgin Galactic’s space plane crash last year in an act of human error that its designer Scaled Composites failed to anticipate, National Transportation Safety Board (NTSB) investigators have said.
Confirming preliminary analysis reached just days after the disaster on 31 October, NTSB concluded that a braking system was unlocked too early, leading to a violent structural failure that tore the vehicle apart mid-flight.
Co-pilot Michael Alsbury died in crash, while pilot Peter Siebold suffered serious injuries after ejecting from the British space tourism venture’s SpaceShipTwo as it broke up.
NTSB investigator Katherine Wilson said in a hearing yesterday that Scaled, which is owned by US aerospace and security giant Northrop Grumman and ran the test flight, did not fully consider human factors in the training for SpaceShipTwo.
Although SpaceShipTwo programme personnel were aware that unlocking the braking system during transonic flight would be catastrophic, she said there were no warnings in the pilot operating handbook. The only documented discussions about the loads on the plane’s tail occurred more than three years before the accident in an email and a PowerPoint presentation.
The probe also found that the Federal Aviation Administration Office of Commercial Space Transportation (FAA AST), which is responsible for evaluating Scaled’s applications for test flight permits, initially failed to recognise that its hazard analysis did not meet regulatory requirements to cover human error.
After granting an initial permit and renewing it once, FAA AST recognised the issue but decided to grant a waiver without Scaled having to ask for it. NTSB said FAA AST did not ensure Scaled was in compliance with the mitigations cited in the waiver from regulatory requirements, “or determine whether those mitigations would adequately address human errors with catastrophic consequences”.
It has made a number of recommendations as part of the investigation, including making the Commercial Spaceflight Federation serve as a safety proxy for the developing private spaceflight industry.
Virgin Galactic, which before the crash had planned to launch commercial operations in early 2015 with a craft that carries two pilots and six passengers, said it has now developed an inhibitor that would stop the braking system from being unlocked early.
Sir Richard Branson, Virgin Galactic’s founder, said NTSB’s investigation will help make “the fledgling commercial space industry safer and better”.
He said: “With the investigation completed, Virgin Galactic can now focus fully on the future with a clean bill of health and a strengthened resolve to achieve its goals.”
The company has said it hopes to resume test flights later this year with a new space plane.
