Virgin Galactic has conducted another unpowered test flight of its space tourism spacecraft over the Southern California desert.
The company says Thursday's glide flight incorporated a special ballast tank filled with water at the rear of the craft to check handling qualities with more weight on board and with the center of gravity shifted to the rear.
Water was then jettisoned to check handling as the center of gravity moved forward.
Virgin Galactic says the ship landed smoothly and safely at Mojave Air & Space Port.
It was the ninth test flight of the ship, named VSS Unity, which is carried aloft by a special carrier aircraft and released.
Data from glide tests is being used to prepare for flights powered by a rocket engine.