WhiteKnightTwo in the Air Over Mojave Today

WhiteKnightTwo outside the FAITH hangar in Mojave for tests on its new brakes. (Credit: Virgin Galactic)

Virgin Galactic Tweeted that Federal Aviation Administration inspectors have signed off on the mother ship’s annual inspection. This is the aircraft’s 150th flight.

Virgin Galactic officials said they planned to fly WhiteKnightTwo again sometime in June. They met that deadline with about 11 hours to spare. Tests of SpaceShipTwo are scheduled to start up again later this summer. Parabolic Arc’s sources indicate the SpaceShipTwo tests could occur in August.

Engineers found cracks along WhiteKnightTwo’s wing spar after taking possession of the aircraft from builder Scaled Composites, sources say. Virgin Galactic CEO George Whitesides disputed that claim, characterizing them as “adhesive imperfections.” Engineers also have been working on WhiteKnightTwo’s brakes, which have experienced problems over the years.

SpaceShipTwo has undergone modifications over the last five months, including the installation of tanks in the wings, sources report. One tank will hold methane, which will be used when the nitrous oxide-nylon engine is fired to ensure a proper burn. The other tank will hold helium, which will be injected at the end of the burn to ensure a smoother shutdown, sources say.