An unmanned spacecraft financed by Amazon.com Inc. CEO Jeff Bezos failed during a test flight last week.

The experimental suborbital space vehicle was developed by Blue Origin, a space startup founded by Amazon.com chief Jeff Bezos.

Bezos announced the failed flight on his company's Web site stating that it was lost during a test flight.

A flight instability drove an angle of attack that triggered our range safety system to terminate thrust on the vehicle,Bezos wrote. Not the outcome any of us wanted, but we're signed up for this to be hard. We're already working on our next development vehicle.

The vehicle reached an altitude of 45,000 feet and a speed of 1.2 times the speed of sound before the flight instability happened.

Bezos founded Blue Origin to develop a vertical takeoff and landing rocketship that would fly passengers to suborbital space. It recently won money from NASA to compete to go into orbit as a space taxi now that the space shuttle fleet is retired, according to The Associated Press.

The Kent, Wash.-based firm operates a test facility in West Texas.

On Aug. 24, the Federal Aviation Administration, which oversees commercial spaceflights, issued a notice to pilots to avoid a 17 nautical mile radius around Van Horn, Texas because of a space operation.

There was no further word about the launch until Friday, when the Wall Street Journal wrote about the spaceship's failure. WSJ said the test did not use federal funds and was not part of the development agreement with NASA.