Camp A Shau was the last of three US Special Forces camps in the strategically important A Shau Valley in South Vietnam. Just two miles from the Laotian border, Camp A Shau sat astride a juncture in the Ho Chi Minh Trail where supplies could continue south, or enter infiltration routes to the cities of Da Nang and Hue, both thirty miles away.

On the morning of 9 March, 1966, four communist regular North Vietnamese Army battalions of 2000 men attacked the camp defended by 17 Americans, 40 Nung mercenaries, and 400 Vietnamese and Montagnard militiamen of the Civilian Irregular Defense Group (CIDG).The communists took part of the camp the first night but the battle raged for the next 36 hours. On the night of 10 March, out of ammunition and water, with staggering loses among the air support, the camp was ordered abandoned. A squadron of US Marine Sikorsky H-34s, HMM-163, flew through what they called “The Tube” in an attempt to evacuate the camp.

In addition to withering fire from all angles, including above, the evacuation proved more difficult than expected. Discipline broke down as the helicopters approached. Many of the Vietnamese switched sides or, with the Montagnards, tried to swarm the helicopters as they landed. Unable to take off because of the weight of soldiers hanging off of the birds, crew chiefs and green berets had to resort to shooting the hangers-on, after yelling and beating didn’t work. In the chaos, this resulted in full-fledged gun battles inside some helicopters, a breakdown in the defense as the NVA surged onto the landing zone, and some special forces leading a breakout into the jungle to escape.

The next day, the squadron conducted a series of search and rescue missions looking for survivors. Over half the garrison was killed or turned, and all but three of HMM-163’s helicopters were either shot down or too damaged to fix. The NVA would turn the A Shau valley into one of its major logistics and staging areas, and over the next four years the US would launch increasingly large operations to clear the valley, culminating with the Battle of Hill 937, aka Hamburger Hill.