Virgin Galactic's suborbital spaceship has made its first solo glide flight from Mojave Air and Space Port in California, as it continues to undergo very strict testing before it can carry tourists to space.

SpaceShipTwo was carried aloft 13,700 m on Sunday morning by its mothership WhiteKnightTwo.

Two pilots controlled the SpaceShipTwo to a safe runway touchdown after it was released. Company officials say it then landed at an airport runway on its own, followed by the mothership. The entire flight took about 25 minutes.

Though the craft did not reach space, it was a major milestone for the Virgin Galactic SpaceShipTwo.

UK billionaire Richard Branson last month introduced his new brand Virgin Galactic in Kuala Lumpur, Malaysia, encouraging people that in 18 months space travel will now be for everyone to enjoy.

He and his team with his latest pioneering project would make commercial space travel, at $200,000 a seat, and even hotel space accommodation possible.

More than 340 people have signed-up for flights to the edge of space to date.