LOS ANGELES -- Federal accident investigators say that tiny pieces of an experimental spaceship that broke up in flight have been found 56 kilometres from the main wreckage area.

Acting National Transportation Safety Board Chairman Christopher Hart said Monday the parts recovered were small enough to have been blown that far by the wind.

The NTSB is moving parts from the Mojave Desert into hangars as it continues its investigation into Friday's demise of Virgin Galactic's space tourism craft.

The agency has not concluded what shattered the aircraft, killing one pilot and injuring the other.

Initial results show that a system to slow the space plane's descent deployed too soon.

Investigators believe once the feathers were unlocked, "aerodynamic forces" buffeting the craft at the speed of sound caused the feathers to start rotating.