Virgin Galactic is now hoping to get SpaceShipTwo into space on a test flight in February, according to multiple sources who attended the company’s gathering of future astronauts in Mojave on Wednesday.
Virgin Group CEO Richard Branson told about 300 future passengers that February is the new target date for having the six-passenger spacecraft fly above the Karmen line located at an altitude of 100 km (62 miles).
One attendee said that Branson didn’t project a lot of confidence about the February date. Overall, the British billionaire seemed rather subdued during in his opening remarks to attendees, lacking some of the enthusiasm he had shown at previous Virgin Galactic events, sources said.
Others who are familiar with the troubled development of SpaceShipTwo’s hybrid engine were less confident in Branson’s prediction. A flight in February is possible, they said, but it might not occur in 2014.
Virgin Galactic had been hoping to fly SpaceShipTwo into space by the end of this year. After the vehicle’s first powered test flight on April 29, Branson boldly predicted that he and his two children, Sam and Holly, would be on the first commercial flight on Christmas Day.
Branson’s prediction caused a lot of eye rolling by people in Mojave who are familiar with the complexity of flight test. Few people believed it would be possible to complete the test program and obtain regulatory approvals to begin commercial service in less than eight months.
The new plan is for Scaled Composites to complete the test program next year, obtain a launch license from the FAA, and to begin commercial service by the end of 2014.
A spaceflight would be a key milestone in a flight test program being run by Scaled Composites, which built SpaceShipTwo and its WhiteKnightTwo carrier aircraft.
SpaceShipTwo has made two powered flights to date using hybrid nitrous oxide-rubber engines that have fired for 16 and 20 seconds. Virgin Galactic has never been specific about the length of a full-duration firing, but sources say it exceeds one minute.
The problem is that despite public claims to the contrary, the nitrous oxide-rubber hybrid has never been hot fired on the ground at full duration, sources indicate. And the engine is not powerful enough even when fully fired to get SpaceShipTwo into space with any actual payloads (i.e., six wealthy passengers).
Even as Scaled Composites has pursued the flight test program and Virgin Galactic has issued optimistic flight predictions that commercial flights are only months away, the two companies have been secretly working on alternatives to the nitrous oxide-rubber engine they have been using to explore SpaceShipTwo’s flight envelope.
Sources report that the development of alternative hybrid designs has been running into trouble. An engine that used nitrous oxide and nylon exploded on Scaled Composites test stand on May 17. The nozzle and rocket casing were thrown clear and the test stand was wrecked. The composite tank holding the nitrous oxide did not explode, but it was damaged to the point where it could not be reused.
Scaled said they were testing an experimental, non-flight engine into which they had introduced flaws on that day. Sources say this is true; however, the explosion and wrecked test stand were not part of the test plan.
There has been work done on developing a liquid-fuel engine, which many experts see as a better long-term solution. A hybrid engine must be replaced after each flight, a process that is a delicate, complicated and expensive. A robust, reusable liquid engine would allow SpaceShipTwo to be refueled and fly again the same day.
It is not clear whether a liquid-fuel replacement is in active development at the moment, or how long it might take to get one ready for flight test on a SpaceShipTwo vehicle.