This photo provided by Virgin Galactic, Virgin Galactic's SpaceShipTwo Unity, attached to mothership, VMS Eve, takes off on Saturday, Dec. 12, 2020 at Spaceport America in southern New Mexico. Saturday morning's test flight marks the third space flight overall for Virgin Galactic as the company looks to begin commercial flights next year. (Virgin Galactic via AP)

A Virgin Galactic test flight Saturday ended prematurely as the spacecraft's rocket motor failed to ignite and it then glided down safely to its landing site in southern New Mexico.

The spacecraft's engine is supposed to ignite moments after the craft is released from a special carrier jet, sending it in a near-vertical climb toward the edge of space.

"After being released from its mothership, the spaceship's onboard computer that monitors the motor lost connection," CEO Michael Colglazier said in a statement. "As designed, this triggered a fail-safe scenario that intentionally halted ignition of the rocket motor."

The pilots flew back to Spaceport America and landed gracefully as usual.

"As we do with every test flight, we are evaluating all the data, including the root cause assessment of the computer communication loss," Colglazier said. "We look forward to sharing information on our next flight window in the near future."

The hourlong flight was to be the first rocket-powered trip to space from Virgin Galactic's headquarters at Spaceport America, a futuristic desert outpost where the aircraft carrying the spacecraft took off at about 8:25 a.m.

Before first announcing the spacecraft's to land and then the problem with the rocket, Virgin Galactic's updates on Twitter about the flight's progress were cryptic and sparse during a 15-minute period that began with an announcement that the spacecraft was "go for release" from the carrier aircraft after reaching high altitude.

The release of the spacecraft from the aircraft usually occurs at about 50,000 feet (15.2 kilometers). At that point, the spaceship would enter a gentle glide and within seconds the rocket motor would be fired and the spaceship's nose pitched to a near-vertical climb.

The suborbital flights are designed to reach an altitude of at least 50 miles (80.5 kilometers) before the is turned off and the crew prepares to reenter the atmosphere and glide to a landing.

After delays because of the coronavirus pandemic and dicey weather earlier this week, the crew had been cleared for a morning launch amid clear conditions.

The spaceship was crewed by two pilots. There was payload belonging to NASA onboard but no passengers.

It's unclear how soon another window will open for Virgin Galactic's next attempt at a powered flight to space. Once the company checks that box, the next phase of final testing for the Virgin Galactic team will involve company mission specialists and engineers being loaded into the spaceship's passenger cabin for powered flights. They will evaluate all the hardware, camera settings and which angles will provide the best views.

Before Saturday, the company already had done two glide flights by the spaceship in New Mexico. This test would have marked the third time overall for Virgin Galactic to reach space, with the first time being from California in December 2018.

Virgin Galactic has yet to announce a firm date for its first commercial .

More than 600 customers from around the world have purchased tickets to be launched into the lower fringes of space where they can experience weightlessness and get a view of the Earth below.