The AGM-28 Hound Dog was designed as a long-range, stand-off air-to-ground strategic missile carried in pairs beneath the wings of B-52 aircraft to help B-52s successfully carry out the strategic bombing offensive. The program began in 1956, and on 16 October 1958 the USAF awarded a contract to North American Aviation, Inc. In April 1959, an AGM-28 was launched from a B-52, and on 21 December 1959 the first production AGM-28 was accepted by the USAF. The Hound Dog had a canard, a delta-wing configuration, an underslung J52 engine, and a self-contained inertial auto-navigational guidance system. Its engine could also supplement those of the host B-52 to increase thrust at takeoff or during cruise, and the missile could then be refueled from the host B-52 wing fuel tanks before launch. This example is depicted as AGM-28A S/N 59-2794, the first A-model missile delivered to Strategic Air Command, which assigned it to Eglin AFB, FL. A total of 703 AGM-28 Hound Dog missiles were produced. Hound Dog missiles were removed from alert duty on 30 June 1975, and the last missile was removed from SAC inventory on 15 June 1978.