October 17, 2014 9:24 am, the X-37B landed on the runway at Vandenberg Air Force Base. The space became top secret drone on earth after a record 674 days mission in space.
What could well make the drone all this time? The information has not been disseminated. This was the third flight of the fleet of two X-37B assembled by Boeing for the Air Force. In total, these space shuttles to scaled spent 1,367 days in space. Next flight in 2015, unknown mission.
Source: “X-37B Orbital Test Vehicle lands at Vandenberg-3 LBS” , Press USAF, October 17, 2014