WhiteKnightTwo, the mothership designed to send Virgin Galactic’s suborbital SpaceShipTwo aloft, made a rougher than expected landing Aug. 19 when its left main landing gear collapsed following a test flight, the Associated Press reported from Mojave, Calif.

“The left main landing gear is damaged, but we don’t yet know if that’s the extent of the damage,” FAA spokesman Ian Gregor told the AP.

Scaled Composites, the Mojave company building the vehicles, said there was a mechanical problem with the left landing gear, describing the event as a “minor incident.”