Today the National Transportation Safety Board (NTSB) concluded their investigation of the in-flight breakup of SpaceShip Two during a test flight on October 31, 2014. In a public hearing at the NTSB’s headquarters in Washington, D.C., the organization’s investigators and analysts presented their findings, conclusions and recommendations in a draft report to the NTSB Board members.
Throughout the discussion, NTSB staff and Board members praised the industry’s strong commitment to transparency and cooperation during the investigation, which helped lead to a more timely and complete resolution of the accident investigation.
The NTSB concluded that “the probable cause of this accident was Scaled Composites’ failure to consider and protect against the possibility that a single human error could result in a catastrophic hazard to the SpaceShip Two vehicle. This failure set the stage for the copilot’s premature unlocking of the feather system as a result of time pressure and vibration and loads that he had not recently experienced, which led to un-commanded feather extension and the subsequent aerodynamic overload and in-flight breakup of the vehicle.”
The NTSB also determined that there was “no evidence of structural, system or rocket motor failures” before the co-pilot’s premature unlocking of the feather system initiated the breakup.
Based on their findings, the NTSB issued ten recommendations related to the accident. The recommendations are directed at both the commercial space industry and FAA AST to improve processes, communication, and collaboration within and between one another. Importantly, none of the recommendations include calls for new regulations or additional government regulatory authority.
The NTSB proposes that the Secretary of Transportation utilize his current authority to improve safety through more collaboration with industry. The NTSB’s draft report reaffirms the integrity of the regulatory framework that currently underpins the commercial spaceflight industry. It adds additional credence to the bipartisan effort in Congress to extend the current framework before key provisions expire in September.
NTSB’s specific recommendations for the commercial spaceflight industry are:
Advise commercial spaceflight operators to work with local emergency response partners to revise emergency procedures for planning to ensure that helicopter and other resources are appropriately deployed during flights; and
Collaborate with FAA AST to develop and issue human factor guidance for operators to use throughout the design and operation of a vehicle. The guidance should address but not be limited ot the human factor issues identified during the SpaceShip Two accident investigation.
“Anybody’s accident is everybody’s accident,” said NTSB Chairman Hart. “When it comes to safety, industry must cooperate and collaborate with each other and with the FAA.”
At the time of the accident, Scaled Composites, a subsidiary of Northrop Grumman Corporation, was responsible for SpaceShip Two’s flight test program under a contract with Virgin Galactic.
Scaled Composites pilot Peter Siebold and copilot Michael Alsbury were conducting the test flight in Spaceship Two when the spacecraft experienced a serious anomaly that resulted in vehicle failure. Michael Alsbury did not survive the accident. Peter Siebold landed safely under parachute with injuries. No members of the public were harmed in the accident, and there were no passengers or customers onboard the vehicle.
SpaceShip Two was a reusable, winged spacecraft designed to repeatedly carry as many as eight people (including the two pilots) into space. The accident occurred during SpaceShip Two’s 55th overall and fourth rocket-powered test flight.