Forward air controllers in the Vietnam War

The forward air controller (FAC) played a significant part in the Vietnam War from the very start. Largely relegated to airborne duty by the constraints of jungled terrain, FACs began operations as early as 1962. Using makeshift propeller-driven aircraft and inadequate radio nets, they became so essential to air operations that the overall need for FACs would not be completely satisfied until 1969. The FAC's expertise as an air strike controller also made him an intelligence source, munitions expert, communication specialist, and above all, the on-scene commander of the strike forces and the start of any subsequent combat search and rescue if necessary.

Present as advisors under Farm Gate, FACs grew even more important as American troops poured into Vietnam after the Tonkin Gulf Incident. The U.S. Air Force (USAF) would swell its FAC complement to as many as 668 FACs in Vietnam by 1968; there were also FACs from the U.S. Army, U.S. Navy, U.S. Marine Corps, and allied nations. For the early years of the war USAF manning levels were at about 70% of need; they finally reached 100% in December 1969. The FACs would be essential participants in close air support in South Vietnam, interdiction efforts against the Ho Chi Minh Trail, supporting a guerrilla war on the Plain of Jars in Laos, and probing home defenses in North Vietnam.

As the war came to center on the Trail in 1969, the FAC role began to be marginalized. Anti-aircraft (AAA) defenses became steadily more aggressive and threatening along the Trail as the bombing of North Vietnam closed down. The communist enemy moved their supply activities to nighttime, quite literally leaving the FACs in the dark. The American response was twofold. They used fixed-wing gunships with electronic sensors to detect communist trucks, and onboard weaponry to destroy them. They also began putting FACs in jet aircraft and in flareships as a counter to the AAA threat. At about the same time, emplaced ground sensors began to complement and overshadow FAC reconnaissance as an intelligence source. FAC guidance of munitions also began to come into play in 1970.

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