XS-1 as it is called, or the first experimental spaceplane, is a venture by Boeing for the Defense Advanced Research Projects Agency (DARPA). The primary goal with XS-1 is to significantly reduce the waiting period from the demand to launch, which in turn is expected to considerably reduce the overall cost of sending something to space.
Aspiring to build a fully reusable unmanned vehicle, DARPA had awarded three commercial launch providers to pitch concepts on short-notice and low-cost access to the space – Northrop Grumman with Virgin Galactic, Masten Space Systems with XCOR Aerospace, and Boeing with Blue Origin, who seems to have made the best progress.
XS-1 Combination of Airplane and Space Launch Vehicle
According to Jess Sponable, Program Manager at DARPA, XS-1 will be an integrated product of important features of both traditional airplane and conventional space launch vehicles. Sponable expressed his satisfaction over the progress made by Boeing through Phase 1 of the XS-1 program and have funded progressions to Phase 2 and Phase 3.
Designing in Phase 2, Flight Tests in Phase 3
By the end of 2019, Boeing will be finishing the designing, construction, and testing of the technology, which includes building a set-up to fire a space vehicle engine 10 times in 10 days. Phase 3, which is scheduled for 2020, will involve real-life flight tests, first up to the speeds of Mach 5 and then Mach 10. The payloads expected to be propelled out of low Earth orbit is between 900 pounds to 3,000 pounds.