The North American Aviation AGM-28 Hound Dog was a supersonic, turbojet-propelled, nuclear armed, air-launched cruise missile developed in 1959 for the United States Air Force. It was primarily designed to be capable of attacking Soviet ground-based air defense sites prior to a potential air attack by B-52 Stratofortress long range bombers during the Cold War. The Hound Dog was first given the designation B-77, then redesignated GAM-77, and finally AGM-28. It was conceived as a temporary standoff missile for the B-52, to be used until the GAM-87 Skybolt air-launched ballistic missile was available. Instead, the Skybolt was cancelled within a few years and the Hound Dog continued to be deployed for a total of 15 years until its replacement by newer missiles, including the AGM-69 SRAM and then the AGM-86 ALCM.