7. B-52s also provided photo reconnaissance missions during the Vietnam War
Prior to the commencement of heavy bombing missions in Vietnam, B-52s flew on reconnaissance missions over South Vietnam. Beginning in May, 1965, B-52s flew on missions throughout South Vietnam, mapping areas as potential targets for the bombing missions of Operation Rolling Thunder. All bombing missions conducted by the B-52s in Vietnam during the year 1965 took place in the South, and most were directed at Viet Cong-controlled regions and communication facilities. The recon missions were flown by unarmed B-52s, other than the presence of the tail gunners. In late 1965, after saturation bombing had been underway for five months, B-52s struck a target whose “target box” extended into Laos. In 1969 SAC, which controlled B-52 operations in Southeast Asia, extended its bombing missions into Cambodia.
The use of the B-52 in Vietnam did not alter the commitment of SAC to the maintenance of two legs of the nuclear triad, aerial bombardment and intercontinental ballistic missiles. A sizable number of B-52s remained unmodified and on alert for potential nuclear strikes. Thus, in the late 1960s, B-52s were in the air on an almost continuous basis. They operated above the Arctic Circle, the South Pacific, and across the United States, as well as in advanced bases in the United Kingdom, and other locales. At the same time the B-58 Hustler bomber, which had first deployed as a nuclear weapon delivery aircraft in 1961, was rapidly retired by SAC, leaving service by the end of the decade. In 1970 the B-52 was the only heavy bomber in the inventory of the United States Air Force.