On Nov. 1, 1964, a Viet Cong mortar attack on Bien Hoa Air Base near Saigon destroyed five B-57B Canberra bombers and two helicopters, while damaging 13 additional B-57B aircraft. That attack largely reflected Canberra losses during the war—most occurred on or close to the ground. For example, four of the bombers that arrived on Aug. 5, 1964, the first deployment of U.S. combat jets to South Vietnam, were lost in poor weather.

Originally intended as a nuclear-strike platform, the B-57’s outstanding ordnance load and ability to loiter over targets made it the ideal plane for ground support and interdiction efforts during the war’s early years.

The U.S. Air Force decided in 1951 to add the British-made English Electric Canberra B.2 to its bomber fleet and selected Glenn Martin Co. to manufacture it under license. Martin’s version, the B-57A Canberra, reduced the crew from three to two while adding wingtip fuel tanks and a low-drag revolving bomb bay door that enabled the aircraft to carry a variety of ordnance. The first planes left the factory in 1953. Only eight B-57As were produced.

The B-model had a redesigned tandem cockpit for the two crewmen, a gun sight, wing ordnance hard points, wing-mounted guns and hydraulic air brakes. The B-57B could carry up to 16 bombs of 100 or 250 pounds in its bomb bay and 3,300 pounds of ordnance—bombs or rocket pods—on the wings.

The Canberra was the first American aircraft to bomb the Viet Cong and strike the Ho Chi Minh Trail. The plane’s nearly 60-minute loiter time and gun armament made it a particularly popular option not only for the trail but also for larger targets in southern Laos.

The Air Force lost 51 Canberras to combat in Vietnam—15 destroyed on the ground and 26 downed by groundfire, mostly over South Vietnam. By 1969, only nine B-57Bs were still operational. They were withdrawn that year, replaced by heavily modified and rebuilt B-57Gs, optimized for low-level, all-weather missions. The Air Force retired the last B-57 in 1983.