The National Transportation Safety Board (NTSB) will meet in public session on Tuesday, July 28, to deliberate and vote on its report on the probable cause of the October 31, 2014 SpaceShipTwo (SS2) crash. The meeting begins at 9:30 am ET and will be webcast on the NTSB website.

The NTSB ordinarily has five members, but there is one vacancy at the moment. The Tuesday meeting is an opportunity for all four members to hear from the NTSB staff at the same time about their findings, conclusions and recommendations. The Board members have had access to factual reports and draft staff reports already, but this is the formal unveiling and opportunity for debate. The Board will vote to adopt or modify the staff’s draft. The Board can make changes to the recommendations, although an NTSB spokesman told SpacePolicyOnline. com on Friday that typically they add or suggest rewordings to staff-developed recommendations rather than making wholesale changes.

The NTSB does not hold public meetings for all of its hundreds of investigations every year, but only for those of significant public interest. NTSB chairman Christopher Hart, who was acting chairman at the time of the SS2 crash, pointed out that this is the first spaceflight accident it has investigated. He was on-site at Mojave Air and Space Port in Mojave, CA, where the crash occurred for the initial phase of the investigation and provided the public briefings.



NTSB Chairman Christopher Hart

Photo credit: NTSB website

The factual documents produced by the staff will be made public on Tuesday at 9:00 am ET, half an hour before the meeting. They will be posted on the NTSB website. Parties to NTSB investigations have access to NTSB’s factual documents during the investigation, but are not allowed to speak about them until the NTSB adopts its report. The parties may submit their own documents responding to the NTSB’s findings both before and after the NTSB adopts the final report that are also made part of the public record, but the parties do not address the Board at the public meeting. In this case, the parties include the FAA, Scaled Composites, and Virgin Galactic.

This is the final action by the Board, although it is possible for a party to file a petition for reconsideration if new, relevant information becomes available that has the potential to change the probable cause.

The technical cause of the crash was evident almost immediately. SS2 co-pilot Michael Alsbury, who died in the crash, prematurely moved one of two levers that activate a feathering system intended to slow the spaceplane during descent. Why he did so and why the feathering system deployed even though the second lever was not activated are among the subjects of the investigation.

SS2 was built by Scaled Composites for Richard Branson’s Virgin Galactic, which plans to send tourists on suborbital space flights using these spaceplanes. The company planned to build five of them. The one destroyed on October 31 was the first and only operational spaceplane. A second spaceplane was already under construction and that is continuing although the date for a test flight is uncertain. Virgin Galactic President George Whitesides said in January that the company will “recover, we’ll learn the hard lessons from the accident, and return to flight.” The company is also developing a version of its system, LauncherOne, that will be used to launch small satellites instead of people.