MOJAVE, Calif. - Virgin Galactic says it expects to make rocket-powered test flights of its passenger spaceship later this year.

The company said Wednesday its spaceship builder partner has been granted an experimental permit from the Federal Aviation Administration -- a move that will allow it to proceed with powered flights.

No timetable has been set for the first launches carrying paying customers, but that'll come after the test program is complete. More than 500 people including actor Ashton Kutcher have signed up with Virgin Galactic for a chance to experience weightlessness during suborbital flights.

Virgin Galactic and Mojave, Calif.-based Scaled Composites have been glide-testing their six-passenger vehicle SpaceShipTwo, which is air-launched from a twin-fuselage carrier airplane.

Work is under way to integrate the rocket motor into SpaceShipTwo.