Boeing to design unmanned, reusable spaceplane XS-1 for DARPA

The US' Defence Advanced Research Projects Agency (DARPA) has commissioned designs for an unmanned, reusable spaceplane.

The advanced design work for the Experimental Spaceplane XS-1, commisioned by  Defence Advanced Research Projects Agency (DARPA), will be completed by Boeing. The XS-1 programme run by the agency, formed part of the US Department of Defence.

Under the programme, a new class of hypersonic aircraft will be created to bolster national security by providing short-notice, low-cost access to space.

XS-1 will help facilitate launches to low-earth orbit in a matter of days, as against months or even years of preparation currently needed to put a single satellite into orbit. Its recurring costs could be as low as $5 million per launch.

Currently, the cheapest low-earth orbit launches were offered by Elon Musk's SpaceX, which could cost around $60 million depending on the mission.

The ambitious project requires "significant advances in both technical capabilities and ground operations," according to DARPA.

In case it proved to be a success, it would "revolutionise" the US' "ability to recover from a catastrophic loss of military or commercial satellites, upon which the nation today is critically dependent."

The aim was to build a fully reusable unmanned vehicle, roughly the size of a business jet, capable of vertical takeoff like a rocket and attaining hypersonic speeds.

The Phantom Express would fly into high suborbital altitudes to launch satellites into orbit before returning to earth and landing horizontally like an airplane.

The unmanned craft, which formed part of the Experimental Spaceplane (XS-1) programme, would release a small expendable upper stage rocket after it reached suborbital altitudes. The upper stage would continue to carry the payload to orbit while the first stage-the spaceplane itself-would return to earth to land on a runway.

"The XS-1 would be neither a traditional airplane nor a conventional launch vehicle but rather a combination of the two, with the goal of lowering launch costs by a factor of ten and replacing today's frustratingly long wait time with launch on demand," said Jess Sponable, DARPA program manager, in a press release.

"We're very pleased with Boeing's progress on the XS-1 through Phase 1 of the program and look forward to continuing our close collaboration in this newly funded progression to Phases 2 and 3-fabrication and flight."