The X-37B Orbiter Flies Secret Missions to Space

X-37B orbiter
The Air Force's X-37B Orbital Test Vehicle mission 4 lands at NASA 's Kennedy Space Center Shuttle Landing Facility, Fla., May 7, 2017. Managed by the Air Force Rapid Capabilities Office, the X-37B program is the newest and most advanced re-entry spacecraft that performs risk reduction, experimentation and concept of operations development for reusable space vehicle technologies. U.S. Air Force

When NASA's space shuttle program was closed down in favor of a new direction in human space travel, the aging orbiter fleet dispersed to various museums across the country, it almost looked like the idea of a "space plane" style orbiter was history. It's well known that the Soviets flew their Buran without crews, and the Chinese have a similar type of capability.

However, the truth is, the idea of and questions about such an orbiter has never died. Sierra Nevada Systems' Dreamchaser is under active development and will fly to space in the next few years. What most people don't know (or didn't until May 2017) was that the United States Air Force has been making test flights of a small orbiter called the X-37B since 2010. So far, four flights have been made, and more are planned and in the future, they will be lofted to space atop a SpaceX Falcon 9 heavy lift rocket. 

Nicknamed "Space Shuttle, Jr", this little orbiter was originally a NASA-led effort to develop a new generation of orbiters in cooperation with the Integrated Defense Systems division of Boeing's Phantomworks section. The Air Force was also involved with helping to fund the development. The original version was called the X-37A, which went through several attempts at drop testing and free flight. Eventually, the project was taken over by the U.S. Department of Defense, which began to develop and test its own version of the spacecraft, the X-37B. Its first mission didn't happen until 2010.

A Fully Autonomous Orbiter

The X-37B doesn't carry crews to space. Instead, it's stuffed with instruments and cameras and is considered more of a testbed for technologies that would work well in space onboard other such orbiting platforms. According to Air Force sources, some of the technology being tested includes flight systems, propulsion technology, avionics, thermal protection (like the tiles used on former shuttles), and guidance and navigation controls. It's designed to be reusable, and the robotic control systems allow it to fly for quite a long time on orbit and then execute a landing similar to the way a drone aircraft is handled.

The materials and equipment tested onboard the X-37B will eventually benefit civilian space needs. For example, improvements in rocket propulsion will be quite useful to future launches of astronauts and payloads to space for NASA. The mission that landed in May 2017 tested ion thruster technology built by Aerojet Rocketdyne that will be used (among other places) on a series of communications satellites.

The Flights of the X-37B

X-37B orbiters (there are two of them) have flown four missions. The mission designations all begins with the letters USA, followed by a number. The first, designated USA-212 was launched on April 22, 2010, atop an Atlas V rocket. It orbited Earth for 224 days and then achieved what's called an "autonomous" landing (meaning it was all computer-controlled) at Vandenburgh Air Force Base in California. It flew again in December 2012, as mission USA 240, staying on orbit for almost 675 days. Its mission was classified and no information is available about its objectives.

The second X-37B took its first flight to orbit on March 5, 2011, and was designated USA-226. It, too, was a classified mission. It stayed i n orbit for just over 468 days before landing at Vandenburgh. Its second mission (USA-261) left Earth on May 20, 2015, and stayed in orbit for 717 days (breaking all known records).  The mission landed at Kennedy Space Center on May 7, 2017 and was more publicized than any other X-37B flights.

Why Have a Secret Orbiter?

The U.S. has always flown "secret" satellites and payloads to space aboard rockets and the space shuttles. The first "mysterious" satellite was actually flown by the Soviets, called Sputnik 1 in 1957. Secret missions are generally believed to be focused on testing equipment for future use, as well as reconnaissance efforts. In terms of equipment testing, space-based systems are continually being refined and updated. Space is a hostile environment for any type of equipment, as is the re-entry process when an orbiter or capsule comes home.  At a very human level, people are always curious about what others are doing. Today, in addition to numerous reconnaissance missions, a number of "civilian" satellites make high-resolution images available to just about anyone who wants to see it, so the value is really more in the analysis of the information they convey.

It's well known that most countries with launch capability can also put their own 'assets' into space. The U.S. is no different from the Russians, Chinese, Japanese, Europeans and others who want information from space. The outcome of such missions helps national security, at the same time that it enables testing of equipment that will be useful to both military and civilian flights in the future.