[Out of Stock] Produced by Boeing, the X-37B Orbital Test Vehicle (OTV) is an unmanned spaceplane, it started life in 1999 as a NASA project but it was taken over by the Department of Defense (DoD) in 2004. The reusable spacecraft conducts orbital flights and is now operated by the US Air Force to demonstrate reusable space technologies. The first orbital flight of the USAF's X-37B took place on 22 April 2010 after it was launched using an Atlas V rocket and landed at Vanderberg AFB on 3rd December 2010 as scheduled. Its aerodynamic design is clearly based on that of the Space Shuttle. The 8.9m-long and 4.99-tonne X-37B has the ability to remain in orbit for up to 270 days propelled by a single Rocketdyne AR-2/3 rocket engine.