According to a news report released in state owned media last week, China is moving forward with development of their own “space plane,” similar to the secretive U.S. Air Force X-37B platform in function, though very different in delivery.
America’s X-37B, which looks quite a bit like a miniature space shuttle, has been in service since 2015, deploying classified payloads and loitering in space for hundreds of days at a time. It’s carried into orbit on an United Launch Alliance Atlas V rocket, which it’s interesting to note, is propelled by Russian sourced RD-180 liquid fuel rocket boosters. Once in orbit, the X-37s small on-board engines are utilized primarily for maneuvering and upon reentry, unlike the shuttle, which used a massive orange fuel tank to supply it’s three primary engines at launch.
The ship itself is not particularly big: at less than 30 feet long and boasting a wingspan of only around 15 feet, you could actually put both X-37s that have been built inside the payload bay of the now-retired space shuttle. The smaller size doesn’t truly compromise much of the spacecraft’s functionality, however, as it does not require a crew, nor crew compartments, to function.
While the artist’s rendering of the planned Chinese autonomous orbital payload delivery vehicle does bear a striking resemblance to America’s X-37 spacecraft, it’s trip to orbit will be more comparable to Paul Allen’s Stratolaunch project, which is currently the largest wingspan aircraft ever built. Like the Stratolaunch, the Chinese spacecraft will be carried to the very cusp of earth’s atmosphere via a heavy lift aircraft, where it will then detach and engage it’s on-board rockets to carry it the rest of the way into orbit.
However, depending on how true the designs are to the artist’s depictions presented in Chinese media, the way in which their carrier aircraft is powered looks to be quite different than the Stratolaunch’s six Boeing 747 engines. Instead, a sleeker almost fighter-jet looking carrier vehicle will ferry their autonomous shuttle to high altitudes using only two, much smaller looking engine platforms – which begs some interesting questions.
The name of the game when it comes to bringing a craft to the edge of space isn’t so much velocity as it is payload lift capacity. If the spacecraft is to deliver valuable payloads into low earth orbit, after all, the aircraft taxiing it to the edge of space must be able to hoist not only the weight of the craft, but sizeable payloads as well. With only two engines on the lift vehicle, it’s possible then that China may intend to utilize scramjet propulsion – a currently experimental engine platform capable of achieving hypersonic speeds.
However, the Chinese design seems to allow less space for payload delivery than the X-37, which may be a byproduct of the craft having to use it’s own engines to propel it out of the earth’s atmosphere, a challenge the X-37 does not face. However, it is also possible that the reduced payload space could mean the Chinese ship has a more pressing priority in orbit than deploying satellites – a controllable arm, for instance could allow for manipulation of other orbital assets, not to mention the possibility of offensive or defensive armaments.
Like all orbital endeavors for the Chinese, the forthcoming space plane is a military operation funded by the People’s Liberation Army via the China Aerospace and Industry Corporation, or CASIC. CASIC has previously specialized in rockets, missiles, satellites, and notably, anti-ship cruise missiles already employing scramjet propulsion.
China claims their drone shuttle will take to the skies by 2030, and because much of the technology required to complete it already exists, that timeline seems about right. Just what it will be doing once it finally does launch, however, may be the more important question to ask.
Feature image courtesy of NASA