THE FLIGHT Beginning on the night of 18 December 1972, waves of B-52 Stratofortresses flew from Andersen Air Force Base, Guam, more than 3,000 miles one way to strike the North Vietnamese heartland. On the first night, 129 B-52s hit seven targets in three waves. The B-52s flew in three-ship cells, dropping 15,000 tons of bombs over eleven days. The North Vietnamese responded with SA-2 surface-to-air missiles; on the night of 20 December, six B-52s were lost in a single strike. After eleven bombers were downed in the first four nights, SAC commander General John C. Meyer ordered a radical change. On 26 December—"the day on which the airpower campaign, and perhaps the future of the U.S. in Vietnam, depended"—120 B-52s struck ten targets simultaneously from four different directions, compressing the entire attack into fifteen minutes. The saturation overwhelmed the enemy's command and control. By 29 December, North Vietnam's SAM supply was exhausted, its airfields unusable, and its air-defense network obliterated. The U.S. paid a steep price: fifteen B-52s lost, along with eleven tactical aircraft. But Hanoi agreed to resume talks. On 27 January 1973, the Paris Peace Accords were signed—one month after Linebacker II ended.