Virgin Galactic’s SpaceShipTwo VSS Unity safely and successfully completed her first supersonic, rocket-powered flight April 5, 2018, after two years of extensive ground and atmospheric testing.
The flight was also significant for Virgin Galactic’s Mojave, California-based, sister manufacturing organization, The Spaceship Company. Unity is the first vehicle to be built from scratch for Virgin Galactic by The Spaceship Company’s team of aerospace engineers and technicians.
VSS Unity benefits from all the data and lessons gathered from the test program of her predecessor vehicle, VSS Enterprise. Unity’s flight expanded the program envelope in rocket burn duration, speed, and altitude achieved.
VSS Unity took off into clear Mojave skies at 8:02am with Mark “Forger” Stucky and Dave Mackay in the cockpit, attached to the WhiteKnightTwo carrier aircraft, VMS Eve, piloted by Mike Masucci and Nicola Pecile.
The mated vehicles climbed to a launch altitude of around 46,500ft over the Sierra Nevada Mountains and while pointing back at Mojave, Eve released Unity. After a few seconds, Unity’s rocket motor was fired, and the pilots aimed the spaceship into an 80° climb, accelerating to Mach 1.87 during the 30 seconds of rocket burn. The hybrid (nitrous oxide/HTPB compound) rocket motor designed, built, and tested by The Spaceship Company powered Unity through the transonic range and into supersonic flight for the first time.
On rocket shutdown, Unity coasted upward to an apogee of 84,271ft before readying for the return. At this stage, the pilots raised the vehicle’s tail booms to a 60° angle to the fuselage, into the feathered configuration. This unique design feature, which is key to a reliable and repeatable re-entry capability for a winged vehicle, incorporates the additional safety mechanisms adopted after the 2014 VSS Enterprise accident during its fourth test flight.
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.
The flight has generated valuable data on flight, motor, and vehicle performance for engineering review.