Boeing’s X-37B Orbital Test Vehicle (OTV) landed at Vandenberg Air Force Base, Calif., on October 17, completing its third and longest test mission since 2010. The unmanned spaceplane under development by the U.S. Air Force Rapid Capabilities Office orbited for 674 days following its launch from Cape Canaveral Air Force Station, Fla., aboard an Atlas V launch vehicle last December.

The first OTV mission started on April 22, 2010, and ended Dec. 3, 2010, after 224 days in orbit. The second OTV mission started March 5, 2011, and ended June 16, 2012, after 468 days on orbit.

“With a program total of 1,367 days on orbit over three missions, these agile and powerful small space vehicles have completed more days in orbit than all 135 Space Shuttle missions combined,” said Ken Torok, Boeing director of experimental systems. “The innovative X-37B combines the best of an aircraft and a spacecraft into an affordable, responsive unmanned vehicle and continues to demonstrate that reusable space vehicles are affordable options that support vital missions.” 

The secretive X-37B program dates to the early 1990s and was earlier managed by NASA and the Defense Advanced Research Projects Agency. According to Boeing, the program’s objectives “include space experimentation, risk reduction and concept-of-operations development for reusable space vehicle technologies that could become key enablers for future space missions.”