DARPA’s Experimental Spaceplane (XS-1) system would have a reusable first stage that would fly to hypersonic speeds at a suborbital altitude.
DARPA this week detailed the next development phase of its reusable Mach 10 satellite taxi capable of carrying and deploying a 3,000- 5,000 lb. satellite into low earth orbit (LEO) at a target cost of less than $5M per launch.
The reusable Experimental Spaceplane (XS-1) XS-1 will demonstrate the potential for low cost and “aircraft-like” high operations payload delivery to orbit. DARPA said Phase 2 and 3 development will likely see a single contract worth $140M (Phase II – $123M, Phase III – $17M). The research agency in 2014 awarded Boeing (working with Blue Origin) Masten Space Systems (working with XCOR Aerospace) and Northrop Grumman Corporation (working with Virgin Galactic) contracts to begin phase 1 XS-1 work.
DARPA’s Experimental Spaceplane (XS-1) system would have a reusable first stage that would fly to hypersonic speeds at a suborbital altitude. At that point, one or more expendable upper stages would separate and deploy a satellite into LEO. The reusable first stage would then return to earth, land and be prepared for the next flight. Modular components, durable thermal protection systems and automatic launch, flight and recovery systems should significantly reduce logistical needs, enabling rapid turnaround between flights.
“During Phase 1 of the XS-1 program, the space industry has evolved rapidly and we intend to take advantage of multiple impressive technological and commercial advances,” said Jess Sponable, DARPA program manager. “We intend to leverage those advances along with our Phase 1 progress to break the cycle of escalating DoD space system launch costs, catalyze lower-cost satellite architectures, and prove that routine and responsive access to space can be achieved at costs an order of magnitude lower than with today’s systems.”
According to DARPA XS-1 has four primary technical goals:
Fly 10 times in a 10-day period (not including weather, range and emergency delays) to demonstrate aircraft-like access to space and eliminate concerns about the cost-effectiveness and reliability of reusable launch.
Achieve flight velocity sufficiently high to enable use of a small (and therefore low-cost) expendable upper stage.
Launch a 900- to 1,500-pound representative payload to demonstrate an immediate responsive launch capability able to support defense department and commercial missions. The same XS-1 vehicle could eventually also launch future 3,000+- pound payloads by using a larger expendable upper stage.
Reduce the cost of access to space for 3,000+-pound payloads, with a goal of approximately $5 million per flight for the operational system, which would include a reusable booster and expendable upper stage(s).