The craft called SpaceShipTwo yesterday reached an altitude of 21,030 metres over California after it was dropped from a carrier aircraft and its rocket was ignited for a 20-second burn.
Two pilots and a flight test engineer were aboard as the craft reached a maximum speed of Mach 1.43, then glided to a landing at Mojave Air and Space Port.
Both the altitude and speed exceeded marks set during the first rocket-powered flight last April.
Virgin Galactic plans to take paying passengers on suborbital flights that briefly enter space. The commercial spaceline is owned by Sir Richard Branson's Virgin Group and Abu Dhabi's aabar Investments PJS.