Science News

Air Force launches 'space plane'

Apr 23, 2010, 14:18 GMT

The X-37B sits on top of an Atlas V rocket lifting off from Space Launch pad Complex-41, Cape Canaveral Air Force Station, Cape Canaveral, Florida, USA, 22 April 2010. EPA/JUSTIN DERNIER

Washington - The US Air Force carried out its first launch late Thursday of the so-called 'space plane,' an unmanned craft designed to fly in space for months at a time.

A rocket carrying the X-37B Orbital Test Vehicle took off at shortly before 8 pm (2400 GMT) from Cape Canaveral, Florida, on a mission that the Air Force hopes will prove the viability of reusable drone access to space.

The mission is to test the guidance and other systems of the X-37B during the flight. Air Force officials say no decision has been made on when it will return to Earth. The planned landing venue is Vandenberg Air Force Base in California.

The Air Force has not disclosed any payloads that the vehicle is carrying or what type of experiments it will conduct. It has a wingspan of 4.5 metres, is 8.9 metres long and weighs 4,990 kilogrammes.

'In all honesty, we don't know when its coming back for sure,' Gary Payton, Air Force under secretary for space programmes, told reporters in the run-up to the flight.

The vehicle is designed to remain in low orbit for up to 270 days. Payton said its return date from this mission will depend on the results of the in-flight systems tests. Built by Boeing's secretive Phantom Works division, the plane is powered by batteries and solar cells.

While the mission is meant to test its systems in space, the vehicle's real value will be determined once it returns to Earth, when the plane will be examined for durability to show whether it can be reused, Payton said.

'Once we get the bird back, (we'll) see what it really takes to turn this bird around,' Payton said.

The X-37 programme began in 1999 under NASA's guidance before being transferred in 2004 to the Pentagon's Defence Advanced Research Projects Agency, or DARPA, before winding up in the hands of the Air Force.

The secretive nature of the project has led to speculation about its role in the military - some say it can be used to spy on communications or to deploy small satellites. Some have expressed concerns it could mark the beginning of the weaponization of space - a notion the Air Force flatly rejects.

'I don't know how this could be called weaponization of space. It's just an updated version of the space shuttle kind of activities in space,' Payton said, pointing to the use of military satellites. 'We, the Air Force, have a suite of military missions in space, and this new vehicle could potentially help us do those missions better.'

A second version of the space plane is already in the works, with a tentative test flight scheduled for sometime in 2011, Payton said.

Officials did not reveal the cost of the programme.