Virgin Galactic returns to flight with its VSS Unity spacecraft

It has been a long road back from a fatal 2014 accident for Virgin Galactic, the splashy spaceship company founded by Sir Richard Branson to bring the masses into space. After its VSS Enterprise crashed into the Mojave Desert during a test flight, killing vehicle co-pilot Michael Alsbury, the company has had to redesign some key safety systems and rebuild its spacecraft. It revealed the VSS Unity in February.

Since then Virgin Galactic has completed a series of ground tests and mating to the "mothership" aircraft, Eve. Following captive carry tests in September, the company performed its first glide test on Saturday, when VSS Unity was released at an altitude of about 15km. The spacecraft reached a velocity of mach 0.6 during its 10-minute descent back to the ground in California. It then made a safe landing at test facilities in Mojave.

According to the company, a preliminary review of the data as well as feedback from the two pilots, Mark Stucky and Dave Mackay, indicates that Saturday's flight went well. However Virgin Galactic engineers will perform a full review of the data and vehicle's performance before clearing the way for additional tests, and eventually powered flights, likely sometime in 2017.

Prior to its catastrophic accident in 2014 the VSS Enterprise had made 55 test flights, reaching a maximum altitude of 22 kilometers during powered missions. The VSS Unity has the same basic airframe and propulsion systems as Enterprise, but has a modified feather locking system, which is used to aid in the descent of the spacecraft. During the fatal flight on Oct. 31, 2014, Alsbury prematurely deployed the system while still making a powered ascent. Unity now includes a mechanical pin to prevent the feather lever from moving when the vehicle is flying in an unsafe flight regime.

Additional challenges await as Unity moves higher into the Earth's atmosphere during its test program. When the spacecraft makes powered flights in the upper atmosphere, engineers will carefully observe how the vehicle’s rocket motor dissipates heat from the rear of the spacecraft, and how it behaves when breaking the sound barrier both during ascent and descent. Company officials have said they will fly passengers—there will be room for six customers on a flight in addition to two crew members—only when they are confident they can safely do so.

In the two years since Virgin's accident, the market for space tourism has changed. One competitor, XCOR, has slowed development of its suborbital Lynx spacecraft. However Blue Origin has made significant strides, flying its New Shepard rocket and spacecraft into suborbital space half a dozen times. Blue Origin says it is on schedule to begin offering private rides into space by 2018.

Listing image by Virgin Galactic