During the 1950s, the base underwent many changes and changed hands from TAC to the Strategic Air Command (SAC). Later that year, on 18 November, the 96th Bombardment Wing, Medium (96 BMW), arrived and began operations with three bomber squadrons and one air refueling squadron. The squadrons eventually flew the first all jet-engined bomber, the B-47 Stratojet and the KC-97 Stratofreighter, a dual-purpose cargo and air-refueling aircraft. By the end of the decade, both of these aircraft would be replaced by aircraft still in the Air Force inventory, the KC-135 Stratotanker and the B-52 Stratofortress. The KC-135 was the first all jet-engined air-refueling aircraft and the B-52 still remains the backbone of the USAF bomber fleet. When the 96th BW moved to Dyess AFB, Texas, the 11th Bombardment Wing (Heavy) activated and stood on alert during the Cold War.