The top secret, unmanned X-37B U.S. Air Force shuttle landed back in California on Friday after a nine-month classified military mission into space.
The Boeing X-37 – also known as the Orbital Test Vehicle – is an American unmanned vertical-takeoff, horizontal-landing (VTHL) spaceplane.
It is operated by the United States Air Force for orbital spaceflight missions intended to demonstrate reusable space technologies.
It is a reusable robotic spaceplane that is a 120% scaled derivative of the X-40A
It began as a NASA project in 1999, then was transferred to the U.S. Department of Defense in 2004. It had its first flight as a drop test on 7 April 2006, at Edwards Air Force Base.
The spaceplane’s first orbital mission, USA-212 was launched on 22 April 2010 using an Atlas V rocket. Its return to Earth on 3 December 2010 was the first test of the vehicle’s heat shield and hypersonic aerodynamic handling. A second X-37B was launched on 5 March 2011 with the mission designation USA-226.
X-37B Orbital Test Vehicle
On 17 November 2006 the U.S. Air Force announced it would develop the X-37B from the NASA X-37A.
The Air Force version is designated X-37B Orbital Test Vehicle (OTV).
The OTV program builds on industry and government investments by DARPA, NASA and the Air Force.
The X-37B effort will be led by the Air Force Rapid Capabilities Office, and includes partnerships with NASA and the Air Force Research Laboratory.
Boeing is the prime contractor for the OTV program.
The X-37B can remain in orbit for up to 270 days at a time.
The Secretary of the Air Force states the OTV program will focus on “risk reduction, experimentation, and operational concept development for reusable space vehicle technologies, in support of long-term developmental space objectives.”
The X-37B was originally scheduled for launch in the payload bay of the Space Shuttle, but following the Columbia accident, it was transferred to a Delta II 7920. It was subsequently transferred to a shrouded configuration on the Atlas V following concerns over the unshrouded spacecraft’s aerodynamic properties during launch.
Following their missions, X-37B spacecraft are to land on a runway at Vandenberg Air Force Base, California, with Edwards Air Force Base as an alternate site.
Manufacturing on the second X-37B, OTV-2 was underway in 2010;
It was completed and was first launched in March 2011.