Another view of this remarkable and little known USAF spaceplane . The Boeing X 37 , also known as the Orbital Test Vehicle OTV , is a reusable unmanned spacecraft . It is boosted into space by a launch vehicle , then reenters Earth ' s atmosphere and lands as a spaceplane . The X 37 is operated by the United States Air Force for orbital spaceflight missions intended to demonstrate reusable space technologies . It is a 120 % scaled derivative of the earlier Boeing X 40 . The X 37 began as a NASA project in 1999 , before being transferred to the U . S . Department of Defense in 2004 . It conducted its first flight as a drop test on 7 April 2006 , at Edwards Air Force Base , California . The spaceplane ' s first orbital mission , USA 212 , was launched on 22 April 2010 using an Atlas V rocket . Its successful return to Earth on 3 December 2010 was the first test of the vehicle ' s heat shield and hypersonic aerodynamic handling . A second X 37 was launched on 5 March 2011 , with the mission designation USA 226 it returned to Earth on 16 June 2012 . A third X 37 mission , USA 240 , launched on 11 December 2012 and landed at Vandenberg AFB on 17 October 2014 . The fourth X 37 mission , USA 261 , launched on 20 May 2015 and is in progress . ~ 37