Tuesday, November 4, 2014

NTSB Updates SpaceShipTwo Loss

Click the arrow to watch the briefing. Video source: NTSBgov YouTube channel.

The National Transportation Safety Board held its final regularly scheduled press briefing Monday afternoon to discuss their investigation into the loss of Virgin Galactic's ShipShipTwo VSS Enterprise.

The Los Angeles Times reports:

The National Transportation Safety Board confirmed Monday night that the copilot who died in the fatal crash of Virgin Galactic's SpaceShipTwo prematurely unlocked the spacecraft's aerodynamic controls.

After some confusion, acting chairman Christopher Hart clarified that 39-year-old Michael Alsbury, who died in Friday's crash, was in the right seat. He flipped a switch to unlock a lever that may have caused the spacecraft's tail to rise and create drag — an action known as “feathering.”

That action occurred moments before SpaceShipTwo "disintegrated," according to the NTSB.

SpaceShipTwo is designed and built by Scaled Composites for Virgin Galactic. If the NTSB concludes that the vehicle design led to pilot error, then Scaled would be responsible for the redesign, not Virgin.

Although Virgin has its own pilots, both pilots at the controls Friday worked for Scaled.

According to a Washington Post report:

Employees at Scaled Composites, the firm that designed the space plane, on Friday were able to watch video camera feeds from inside the cockpit and outside the spaceship during its flight.

“There are dozens of reasons why mistakes like this one could be made,” said another Scaled test pilot.

That pilot went on to explain that there was a rule that anyone flying the spaceship could not re-configure the vehicle without the verbal acknowledgment of both pilot and co-pilot. It is unclear whether that protocol was followed. Normally, the co-pilot would announce when Mach 1.4 had been reached — the proper speed to unlock the feather. The pilot would acknowledge and command the co-pilot to unlock the feather. Once the feather was unlocked, the co-pilot would announce the maneuver had been completed.

A number of sources, who spoke on the condition of anonymity because the company has forbidden interviews with the media, described seeing Alsbury unlock the feather and then appear to realize there was an error, moving quickly as if he was trying to shut off the motor, but it was too late.

These sources said that within the company, there is a growing recognition that Alsbury, the co-pilot, unlocked the feather early, although it is not clear why. Colleagues say Alsbury was one of the sharpest test pilots on the team, with more than 1,600 hours of flight experience in more than nine different aircraft.

No comments:

Post a Comment