X-37B Completes 220-Day Mission

LOS ANGELES — The U.S. Air Force is reviewing test data from the first X-37B Orbital Test Vehicle (OTV-1), which completed a picture-perfect autonomous landing at 1:16 a.m. Pacific Time at Vandenberg AFB, Calif., on Dec. 3 after a 220-day space mission. The flight is the first successful runway recovery of an autonomous space vehicle since the 1988 demonstration launch and landing of the former Soviet Union’s Buran unmanned space shuttle, and more important for the Air Force, marks a first step toward deployment of a fully reusable, responsive space capability. Lessons learned from the secret project will be used for mission planning of the second Boeing-built X-37B, OTV-2, currently being prepared for launch from Cape Canaveral Air Force Station, Fla., on an Atlas V in the March-April 2011 time period. The Air Force Rapid Capabilities Office (Afrco), which manages the X-37B program, says “OTV-1’s de-orbit and landing mark the transition from the on-orbit demonstration phase to a refurbishment phase,” but gives no indication when it will return to space. Lt. Col. Troy Giese, X-37B program manager from Afrco, says “the program completed all the on-orbit objectives for the first mission.” Although most objectives remain classified, it is known the flight was aimed primarily at vetting vehicle systems and design features, with a secondary emphasis on the more advanced sensor technology likely to feature more prominently in follow-up missions. Vehicle technology test targets for OTV-1 included advanced guidance, navigation and control, thermal protection systems, avionics, high-temperature structures and seals, conformal reusable insulation, and lightweight electromechanical flight systems. Without knowing additional mission details it is already clear that Friday’s landing, following its April 20 launch on an Atlas V, marks the successful accomplishment of several key targets, including autonomous orbital flight, reentry and landing, as well as demonstrations of long-duration space technology experimentation and testing. The vehicle was operated throughout the mission by Air Force Space Command’s 3rd Space Experimentation Sqdn. based at Schriever AFB, Colo. With autonomous control and recovery now demonstrated, the OTV-2 follow-on flight is expected to focus more on testing of additional spacecraft technology and deployable payloads the OTV will carry in its 7 x 4-ft. payload bay. Originally built for a NASA program, the X-37B was taken over by the Air Force, which initially worked the program in conjunction with the Air Force Research Laboratory and Defense Advanced Research Projects Agency (Darpa). The 29-ft. long, 15-ft. span vehicle, resembles a small space shuttle in overall form, and was designed to test human spaceflight technologies for NASA before transitioning to Darpa in 2004 for use in its Approach & Landing Test Vehicle program.