Friday's test was the SpaceShipTwo's 35th flight. The test flight, its first in more than nine months, was intended to be preparation for future trips farther than 62 miles in altitude. Virgin Galactic changed the SpaceShipTwo's fuel mixture from rubber-based to a plastic-based mix to improve its engine performance, but it's not yet known if this was related to the crash.
"We will work closely with relevant authorities to determine the cause of this accident," the company said in a statement. Roughly 800 potential passengers paid $250,000 to ride in the plane. Mojave Air & Space Port, from where the Virgin Galactic plane was flown, has scheduled a press conference for 5:00 p.m. eastern time on Friday.