Virgin Galactic’s VSS Unity performs a burn during July 11 flight. Credit: Virgin Galactic

WASHINGTON — The Federal Aviation Administration said Sept. 29 that it completed its investigation into a problem on Virgin Galactic’s most recent SpaceShipTwo flight, allowing the company to resume flights of the suborbital spaceplane.

The FAA said it determined SpaceShipTwo deviated from its assigned airspace on its flight July 11 that took six people, including company founder Richard Branson, to an altitude of more than 80 kilometers. The company also failed to communicate that deviation with the FAA.

“The FAA required Virgin Galactic to implement changes on how it communicates to the FAA during flight operations to keep the public safe,” the FAA concluded in a brief statement. “Virgin Galactic has made the required changes and can return to flight operations.”

Asked about those changes, an FAA spokesperson referred to a separate statement from Virgin Galactic. The company said its corrective changes include new calculations to expand the protected airspace during SpaceShipTwo flights. “Designating a larger area will ensure that Virgin Galactic has ample protected airspace for a variety of possible flight trajectories during spaceflight missions,” the company stated.

Virgin Galactic also said that it would also make changes to its flight procedures “to ensure real-time mission notifications to FAA Air Traffic Control.”

“We appreciate the FAA’s thorough review of this inquiry,” Michael Colglazier, Virgin Galactic’s chief executive, said in a statement. “The updates to our airspace and real-time mission notification protocols will strengthen our preparations as we move closer to the commercial launch of our spaceflight experience.”

Neither the FAA nor Virgin Galactic elaborated on the issue during the July flight, known as “Unity 22” by the company, that triggered the investigation. The FAA announced the investigation Sept. 2, the day after an article in The New Yorker revealed that the vehicle’s pilots ignored an “entry glide cone” warning during its rocket-powered ascent, indicating that the vehicle was not climbing steeply enough. The warning meant that SpaceShipTwo was outside the volume of airspace where it could safely glide back to the runway at Spaceport America in New Mexico.

SpaceShipTwo did make it back to the runway without incident, and after the landing company officials didn’t mention that warning or any other problems with the flight. However, the vehicle flew outside of its designated airspace for a time during its descent, something the company acknowledged after The New Yorker article and blamed on high winds at upper altitudes.

While the FAA investigation was in progress, Virgin Galactic said it was looking into a potential manufacturing defect in a component of the vehicle’s flight control actuation system. The issue, the company said at the time, was unrelated to the incident on the July flight that triggered the FAA investigation.

Virgin Galactic said Sept. 10 it was postponing the next SpaceShipTwo flight, a research flight for the Italian Air Force called Unity 23, to no earlier than mid-October. The company didn’t update that schedule in its announcement about the end of the FAA investigation.

Unity 23 will be the last SpaceShipTwo flight until at least the latter half of 2022. Virgin Galactic said in August that, after Unity 23, it would start extensive maintenance on both SpaceShipTwo and its WhiteKnightTwo carrier aircraft to allow both to fly more frequently. The company expects that commercial flights of SpaceShipTwo will not resume until late in the third quarter of 2022.

Jeff Foust writes about space policy, commercial space, and related topics for SpaceNews. He earned a Ph.D. in planetary sciences from the Massachusetts Institute of Technology and a bachelor’s degree with honors in geophysics and planetary science...