According to Parabolic Arc, Virgin Galactic’s SpaceShipTwo experienced a stall upon releasing from carrier mothership WhiteKnightTwo during a drop test on September 29, 2011. The test, ID 73/GF16 conducted by pilot Stucky, copilot Nichols and Flight Test Engineer Persall, lasted 7 minutes and 17 seconds, and ended as planned.
Test card called for releasing the Spaceship from WhiteKnightTwo and immediately entering a rapid descent. Upon release, the Spaceship experienced a downward pitch rate that caused a stall of the tails. The crew followed procedure, selecting the feather mode to revert to a benign condition. The crew then defeathered and had a nominal return to base. Great flying by the team and good demo of feather system.
According to Virgin Galactic’s Commercial Director Stephen Attenborough, the company is considering starting commercial activities in 18 months: “[Launching our first commercial flight] 18 months to two years from now is achievable,” he said, “but that isn’t to say that we will achieve it. The only thing that will extend that expected timeline is if something comes up during the remainder of the test flight program.” Read a definiton of stall.