OTV-4 mission concludes as X-37 returns to Earth.
After nearly two years in space, the U.S. Air Force’s classified space shuttle, the Orbital Test Vehicle X-37B, returned to Earth, landing on Kennedy Space Center’s Shuttle Landing Facility runway shortly before 8am EDT.
Officially known as the AFSPC-5 mission, OTV-4 launched on May 20, 2015, atop an Atlas V rocket. That same rocket also lifted the Planetary Society’s solar sailing cubesat, LightSail-1 into orbit on its own groundbreaking mission. Spending over 717 days in space, the OTV-4 mission is the longest mission thus far of the program’s four flights.
Measuring 29 feet long with a wingspan of 15 feet, the X-37B is a robotic spaceplane with a payload bay ideal for small payloads. While the specific milestones for this flight were classified, at least two of the experiments included the testing of an electric engine and materials exposure pallets.
The first three flights of the OTV program landed at Vandenberg Air Force Base in California, though OTV-4 became the first to land in Florida. By landing at the same spaceport which it left from, OTV operations are expected to streamline and potentially allow for faster times in between missions. One of Kennedy’s three Orbiter Processing Facilities is used by the Air Force to house the two X-37 spaceplanes in between missions.
As seen in the gifs above - taken from video of the vehicle’s landing - the spaceplane glides past a model of another famous space plane, the Space Shuttle. The Inspiration, which once sat outside the U.S. Astronaut Hall of Fame in Titusville, was moved to the SLF for restoration ahead of a nationwide tour promoting aerospace science and STEM fields.
See our coverage of the AFSPC-5 mission here.