Virgin Galactic could resume test flights of its experimental rocket-powered spaceship as early as next summer if it can finish building a replacement craft, despite the recent crash of SpaceShipTwo and death of its co-pilot during a test flight over the California desert.
The composite shell and tail section of the new craft have been constructed at the Virgin Galactic's manufacturing plant in Mojave, California.
While the new ship is said to be 65% complete, Virgin Galactic chief executive George Whitesides said there was much work to be done, from relatively simple things such as installing windows to the more complex fitting of flight controls and other wiring.
The ship, called SpaceShipTwo Serial No 2, will replace the craft that was destroyed last week after its feathering system that controls descent deployed prematurely and aerodynamic forces ripped it apart, killing the co-pilot and seriously injuring the pilot.
In the wake of the accident, workers have focused on building the new ship.
"That's provided some solace to all of us, and I think there's sort of a therapeutic benefit to folks to be able to put their energies into constructive work," Whitesides said.
"There was no question it was a tragic setback, but it's one from which we can recover," he added. "With Serial No 2, we'll be putting a stronger, even better ship into initial commercial service and I think we'll be able to get back into test flights soon and carry forward."
Whitesides said the company, founded by Virgin tycoon Sir Richard Branson, would be able to continue flying its mother ship - the much larger jet-powered plane that launches the rocket ship at higher altitudes - while investigators look into the cause of the deadly crash with the company's co-operation.
It is possible that test flights for the next spaceship could begin within six months, before the investigation is scheduled to conclude, Whitesides said.
Virgin Galactic has an experimental permit from the Federal Aviation Administration to test its spacecraft. In October the company had received approval from the agency to resume rocket-powered flights.
The National Transportation Safety Board (NTSB) said there's nothing preventing Virgin from continuing to fly, but it wasn't immediately clear if the company would have to file another request with the FAA under its existing permit to start rocket-powered flights when the new ship is ready next year.
However, speculation continues about how far the accident will push back the project, with some experts calling for the firm to end the programme.
This includes Carolynne Campbell-Knight, lead expert on rocket propulsion for the Netherlands-based International Association for the Advancement of Space Safety (IAASS), who previously said: "They should stop, give up.
"Go away and do something they might be good at like selling mobile phones - they should stay out of the space business."
She pointed to the use of nitrous oxide fuel as a possible cause of the crash and stated she had contacted those involved in the project in around 2009 or 2010 to raise her concerns about its use.
However, based on information the NTSB have released about their investigation to date, it has recovered the intact engine and rocket propulsion fuel tanks with no signs of burn through or mid-air explosion. “This definitively dismisses the premature and inaccurate speculation that the problem was related to the engine or the fuel,” said Virgin Galactic.
Virgin Galactic envisages flights with six passengers climbing more than 62 miles above Earth. Seats sell for £157,000, and the company says it has booked passengers including Justin Bieber, Ashton Kutcher and Russell Brand. A few more passengers signed on this week, Whitesides said.
Scaled Composites is developing the spacecraft for Virgin Galactic.
When the new ship is ready next year, the FAA will conduct a more extensive review to ensure whatever caused the crash has been addressed, before allowing test flights to resume.