The pilot of Virgin Galactic’s SpaceShipTwo was still strapped to his seat as the vehicle broke apart around him during a test flight in the Antelope Valley last month, according to media reports.

Also, the Wall Street Journal reported that the space tourism company, based at the Mojave Air & Space Port, had experienced problems with its SpaceShipTwo prior to the crash last month that killed a co-pilot in the Mojave Desert.

Pilot Peter Siebold, 43, told federal investigators that he managed to unbuckle himself from the seat and parachute down. Co-pilot Michael Alsbury, 39, was killed.

SpaceShipTwo crashed Oct. 31 just minutes after being dropped by carrier aircraft WhiteKnightTwo at an altitude of more than 50,000 feet. Debris was found in empty Mojave Desert scrub just east of Red Rock Canyon Park.

The cause of the accident is under investigation by the National Transportation Safety Board. A preliminary finding has focused on pilot error, with indications that Alsbury prematurely released a lever unlocking the moveable tail that slows the spacecraft down after reaching suborbital altitude.

Siebold told investigators he was not aware that Alsbury released that lever, according to the Los Angeles Times.

Meanwhile, the Wall Street Journal on Thursday reported difficulties by Virgin Galactic engineers in developing the spacecraft and having it meet the deadline of commercial flights set by founder Richard Branson.

One problem Virgin Galactic experienced was a lack of power in the motor to get the vehicle to the required 62-mile altitude that defines space and would allow passengers to experience weightlessness. Sierra Nevada Corp., the Sparks, Nev. engine maker, said that Virgin Galactic was making the spacecraft too heavy and suggested flying fewer than the six passengers it had anticipated, the Journal story said.

Another problem cited in the story was potential fuel seepage into the center wing section of WhiteKnightTwo that threatened to compromise its strength. Michael Moses, head of operations for Virgin Galactic, was quoted in the story saying that management didn’t cut corners on safety or conducting flight tests.