By the middle of this century around 2050, who knows a planet in our solar system could well be a holiday destination for the very rich, looking for an adventurous holiday! The work has started, and Boeing Aircraft Company has been selected by the US Defence Advance Research Project Agency (DARPA) to design and build a reusable hyper-sonic space-plane that will be flying into suborbital altitudes, that can land horizontally!
Designated as XS-1 it would neither be a traditional airplane nor a conventional space launch vehicle but a combination of the two! DARPA’s programme manager for the project, states: “We are very pleased with Boeing’s progress on the XS-1 through Phase 1 of the programme.” They look forward to continue ahead with close collaboration of both the parties DARPA and Boeing two Phase 2 and 3 that will progress through fabrication, assembly, testing and finally the flight of the ‘Space-plane’! Unlike the Air Force’s X-37B unmanned space-plane that is launched on top an Atlas V rocket; the XS-1 will launch vertically on its own internal combustion engine using cryogenic propellants - liquid oxygen and liquid hydrogen. The plane being developed (named The Phantom Express), and roughly similar in size of a ‘business jet aircraft’ would be flying at hyper-sonic speeds over Mach5, before releasing the satellite-launching second stage, that will carry a payload of up to 3,000 pounds the rest of the way to low Earth orbit!
Phase 2 the next phase of the Experimental Space-plane programme covers design, construction and testing of the craft, that will include 10 test firing of the propulsion system over 10 days to demonstrate that the system is robust enough for quick turnaround launches, Phase 2 is expected to cover through 2019.
Then the US defence agency along with Boeing hope to carry out flight tests in 2020 during Phase 3.A total of around 12 to 15 flights are tentatively planned, with the first few conducted as shake-down flights to extensively test the space-plane. After these initial flights are completed, DARPA desires to launch the XS-1, ten times in ten days, culminating with a flight carrying the upper stage satellite delivery system!
If the programme is successful DARPA predicts the XS-1 could operate with costs under US$5 million per launch! The XS-1 will be using the Aerojet Rocketdyne AR-22 engines - modified space shuttle main engines - composite materials for propellant tanks, autonomous flight control technologies, and hybrid composite-metallic wings and surfaces to withstand the high stress of hyper-sonic flight and temperatures as high as 2,000 degree Fahrenheit!
“This new space plane (Phantom Express) is designed to disrupt and transform the satellite launch process as is known now. It is creating a new on-demand space launch capability that can be achieved more affordably and with less risk” as stated by Darry Davis, president of Boeing Phantom Works, recently!
Apart from providing launch services, DARPA plans to share key design specifications with commercial space-flight companies. This will help the commercial sector to take advantages of this XS-1 technology to reduce launch cost across the board. Over the next two years, we could see some engine test fires, and then come 2020, if all goes according to the plan, the first ship in the Experimental Spaceplane programme will take to the skies!
(Information is sourced from DARPA, and was published in the current issue of ‘Popular Mechanics’ from where it is reproduced).
Engr. S.A.Mansoor, Dhaka