The Boost Glide Reentry Vehicle (BGRV) was a classified United States Air Force program to investigate missile maneuvering at hypersonic speeds after reentry into the atmosphere. Upon reentry, flight control was achieved by using aft trim flares and a reaction jet system commanded from an onboard inertial guidance system. A BGRV was launched on 26 February 1968, from Vandenberg Air Force Base by an Atlas F to the area of Wake Island in the Pacific, collecting data that proved valuable in developing later maneuvering reentry vehicles.