Virgin Galactic completes first supersonic mission since 2014 fatal test crash

SpaceShipTwo VSS Unity mission was a success

Virgin Galactic has announced the successful completion of its SpaceShipTwo VSS Unity mission, reporting a safe landing of its first supersonic, rocket-powered flight.

The completed mission is the first test the space company has carried out since the fatal crash of the 2014 mission that killed one of its pilots, so it goes without saying there was a lot riding on it.

"After two years of extensive ground and atmospheric testing, the passing of this milestone marks the start of the final portion of Unity's flight test program," Virgin said in a celebratory post.

"VSS Unity benefits from all the data and lessons gathered from the test program of her predecessor vehicle, VSS Enterprise."

Virgin Galactic posted a video of the new SpaceShipTwo, VSS Unity and said the flight saw an "envelope expansion" for the program as a whole in terms of rocket burn duration, speed and altitude achieved.

"The mated vehicles climbed to a launch altitude of around 46,500ft over the Sierra Nevada Mountains and while pointing back at Mojave, Eve executed a clean release of Unity," the company explained.

"After a few seconds, Unity's rocket motor was brought to life and the pilots aimed the spaceship upwards into an 80 degree climb, accelerating to Mach 1.87 during the 30 seconds of rocket burn."

The hybrid rocket motor, which was designed, built and tested by The Spaceship Company, powered Unity through the transonic range and into supersonic flight before preparing for its return, Virgin said.

"On rocket shutdown, Unity continued an upwards coast to an apogee of 84,271ft before readying for the downhill return," Virgin explained. "At this stage, the pilots raised the vehicle's tail booms to a 60 degree angle to the fuselage, into the ‘feathered' configuration."

This design feature is apparently key to a reliable re-entry capability for a winged vehicle, and incorporates the additional safety mechanisms adopted after the 2014 VSS Enterprise test flight accident.

"At around 50,000ft, the tail-booms were lowered again and, while jettisoning the remaining oxidizer, Unity turned towards Mojave for the glide home and a smooth runway landing."