Houston, TX – The U.S. Space Force’s X-37B space plane launched on its sixth mission on May 16, just two weeks prior to the SpaceX/NASA Dem-2. Like the space shuttle, the solar-powered X-37B space plane launches vertically, with the aid of a rocket, and cruises back to Earth for a runway landing.
The robotic vehicle resembles NASA’s famous space shuttle but is much smaller. The X-37B is about 29 feet long and 9.5 feet tall, with a wingspan just less than 15 feet. At launch, it weighs 11,000 pounds. The X-37B’s payload bay measures seven feet long by four feet wide — about the size of a pickup truck bed. Air Force officials will comment only on the overall goals of the program, stressing that each payload is classified.
History of the X-37B
The X-37 program started in 1999 with NASA, which initially planned to construct two vehicles: an Approach and Landing Test Vehicle (ALTV) and an Orbital Vehicle. NASA transferred the project to the U.S. military in 2004 — specifically, the Defense Advanced Research Projects Agency (DARPA). At that point, X-37 became a classified project. DARPA finished the ALTV part of the program in 2006, conducting a series of captive-carry and free-flight tests. NASA’s envisioned Orbital Vehicle was never built, but it served as the inspiration for the space plane that came to be called the X-37B.
The X-37B program is now run by the Air Force’s Rapid Capabilities Office, with mission control for orbital flights based at the 3rd Space Experimentation Squadron at Schriever Air Force Base in Colorado. The space planes are built by Boeing’s Phantom Works division.
Two different X-37B vehicles have flown a total of six missions, which are known as OTV-1, OTV-2, OTV-3 and OTV-4 (short for Orbital Test Vehicle). Five flights have reached space with the help of United Launch Alliance’s Atlas V rocket. The sixth launched in May 2020 on a SpaceX Falcon 9 rocket.
OTV-1 blasted off in April 2010 and stayed aloft for 224 days. OTV-2 stayed in space for more than twice as long, launching in March 2011 and returning to Earth 468 days later, in June 2012. OTV-3, which uses the same vehicle that flew the OTV-1 mission, began on Dec. 11, 2012, and ended 674 days later, in October 2014. The OTV-4 mission marked the second flight for the X-37B that flew OTV-2. OTV-4 began on May 20, 2015, and broke OTV-3’s duration record on March 25, 2017. After 718 days in space, the OTV-4 mission ended with a smooth runway landing on May 7, 2017. It was the first X-37B landing at NASA’s Shuttle Landing Facility at the Kennedy Space Center in Cape Canaveral, Florida. The three previous missions landed at Vandenberg Air Force Base.
The OTV-5 mission launched on Sept. 7, 2017 on SpaceX’s Falcon 9 rocket, lifting off from the historic Launch Complex 39A at NASA’s Kennedy Space Center (KSC) in Florida. The mission lasted 780 days (another record) carried the Air Force Research Laboratory Advanced Structurally Embedded Thermal Spreader, an experiment designed to “test experimental electronics and oscillating heat pipe technologies in the long-duration space environment,” according to an Air Force statement. It also carried several other experiments and small satellites. OTV-5 landed on Oct. 27, 2019 at NASA’s Shuttle Landing Facility, marking the second time an X-27B has done so.
All X-37B missions to date have launched from Cape Canaveral Air Force Base in Florida. While the first three touched down at California’s Vandenberg Air Force Base, future missions beyond OTV-4 may continue to land at NASA’s Kennedy Space Center in Florida, right next door to Cape Canaveral. Boeing is using an old NASA space shuttle hangar at KSC to service the X-37B space planes for the U.S. Air Force.