The United States Defence Advanced Research Projects Agency (DARPA) has chosen Boeing to build a spaceplane able to launch 10 payloads in 10 days to fight the prospect of destroyed satellites causing chaos in the future.
According to the agency, the Experimental Spaceplane (XS-1) program aims to bring to life a fleet of hypersonic aircraft that can "revolutionize the Nation's ability to recover from a catastrophic loss of military or commercial satellites, upon which the Nation today is critically dependent."
Boeing was awarded the contract to create a craft which will provide short-notice, low-cost access to space, but the project is a serious challenge.
As DARPA notes, we don't have the capability to launch substantial payloads to low Earth orbit in days at the moment. Instead, it takes months or years of preparation to launch a satellite or two -- but if in the future there is an incident in which we lose critical satellites en masse, we need to have a backup plan.
In order to achieve this goal, Boeing will need to make serious strides in both technology and ground operations.
The XS-1, "roughly the size of a business jet," will take off vertically to reach hypersonic speeds. DARPA hopes that the spaceplane will launch with no external boosters -- cutting the expense of the vehicle -- and will be powered only by cryogenic technology.
Once the plane reaches orbit, the XS-1 would deploy a 3,000-pound satellite. As the vehicle would be able to use the same launching stage repeatedly, it is hoped that after landing and being prepared for the next flight, the XS-1 will be able to deploy ten satellites in as many days, with a turnaround "potentially within hours."
DARPA and Boeing envision the XS-1 utilizing lightweight composite cryogenic propellant tanks able to hold liquid oxygen and liquid hydrogen, as well as hybrid composite-metallic wings for flight which are able to withstand suborbital hypersonic flight and temperatures of over 2,000 Fahrenheit.
In addition, the craft will use a range of flight-cancelling and autonomous flight technologies, including some already used by DARPA's Airborne Launch Assist Space Access (ALASA) program.
If the program is a success, it is hoped that each launch could cost less than $5 million each, making commercial and military launches more affordable.
"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. "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."
Boeing is in the XS-1 concept first stage, and as designs and technologies sourced from DARPA, NASA, and the US Air Force are integrated and refined, it is hoped that the spaceplane will be ready by 2019, with up to 15 test flights scheduled for 2020.