The investigation into what caused the Virgin Galactic test flight to crash could take as long as 12 months, lead investigator Chris Hart has said.
Mr Hart, who is acting head of the National Transportation Safety Board, also told reporters that his team would interview injured co-pilot Peter Siebold when he was ready.
Sir Richard Branson has told ITV News that he felt "uncomfortable" over the weekend as "self-proclaimed experts" said that an explosion brought down the Virgin Galactic space-plane.
He said: "We knew there was no explosion. We knew that the fuel tanks and engine were all intact, and we found it uncomfortable over the weekend when so many self-proclaimed experts, particularly in the UK, came out saying there had been an explosion."
For the full interview with Sir Richard Branson watch the lunchtime ITV News at 1.30pm.
Faced with a five-mile debris trail and masses of technical data, the team investigating the crash of SpaceShipTwo have their work cut out.
The loss is a tragedy for this small tight-knit team that dreams of making the trip into space accessible to travellers not just astronauts.