DESIGN FOR NEXT-GENERATION SPACE PLANE

The Defense Advanced Research Projects Agency (DARPA) has selected The Boeing Company to complete advanced design work for the Agency’s Experimental Space plane (XS-1) programme which aims to build and fly the first of an entirely new class of hypersonic aircraft that would bolster national security by providing short-notice, low-cost access to space. The programme aims to achieve a capability well out of reach today—launches to low Earth orbit in days, as compared to the months or years of preparation currently needed to get a single satellite into orbit. “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 10 and replacing today’s frustratingly long waiting time with launch on demand,” said Jess Sponable, DARPA Program Manager. The XS-1 programme envisions a fully reusable UAV, roughly the size of a business jet, which would take-off vertically like a rocket and fly to hypersonic speeds. The vehicle would be launched with no external boosters, powered solely by self-contained cryogenic propellants. Upon reaching a high suborbital altitude, the booster would release an expendable upper stage able to deploy a 3,000-pound satellite into polar orbit. The reusable first stage would then bank and return to the Earth, landing horizontally like an aircraft and be prepared for the next flight, potentially within hours.