Riding a SpaceX rocket
The fifth mission, known as OTV-5 (for “orbital test vehicle”) launched from the Kennedy Space Center on Sept. 7, 2017. That means it was in space for 780 days, or more than two years. This mission started with a liftoff atop a SpaceX Falcon 9 rocket.
The Air Force doesn’t reveal much about what the unmanned X-37B spacecraft do while circling the planet, but Randy Walden, director of the Air Force Rapid Capabilities Office, did say this much: “This mission successfully hosted Air Force Research Laboratory experiments, among others, as well as providing a ride for small satellites.”