Virgin Galactic's VSS Unity has taken to the sky on its first free flight. The suborbital passenger spacecraft was dropped by the WhiteKnightTwo mothership at the Virgin Galactic test site over the Mojave Desert during one hour 20 minute flight that included a ten minute, unpowered free flight to test the craft's systems and collect telemetry data.

VSS Unity was piloted by Mark Stucky and Dave Mackay while WhiteKnightTwo was under control of Mike Masucci and Todd Ericsson and flight test engineer Dustin Mosher. It was the fifth flight of the spacecraft and the first free flight, while WhiteKnightTwo has flown 218 times.

Unity is the second version of the company's SpaceShipTwo and was built by Virgin Galactic's subsidiary, the Spaceship Company. During Saturday's flight, Unity was released at an altitude of 50,000 ft (15,240 m) and reached a maximum velocity of Mach 0.6 (457 mph, 735 km/h, 397 kt). Virgin Galactic said that initial telemetry indicates the flight went "extremely well."

The free flight milestone follows Virgin Galactic's recertification after a fatal accident during a test flight in 2014, when VSS Enterprise (SS2-001) broke up in midair 13 seconds after being dropped from the WhiteKnightTwo mothership. This resulted in the death of the co-pilot Michael Alsbury and severe injury to the pilot, Peter Siebold, who was thrown clear as the craft disintegrated.

Virgin Galactic is now analyzing data from the latest test flight and will use it to determine when Unity will be fit to carry out its first rocket-powered flight, which is expected to folllow a further series of glide tests.

Virgin Galactic