Forward air control
Forward air control is the provision of guidance to close air support aircraft intended to ensure that their attack hits the intended target and does not injure friendly troops. This task is carried out by a forward air controller.
A primary forward air control function is ensuring the safety of friendly troops during close air support. Enemy targets in the front line are often close to friendly forces and therefore friendly forces are at risk of friendly fire through proximity during air attack. The danger is twofold: the bombing pilot cannot identify the target clearly, and is not aware of the locations of friendly forces. Camouflage, a constantly changing situation and the fog of war all increase the risk. Present day doctrine holds that Forward Air Controllers are not needed for air interdiction, although there has been such use of FACs in the past.
An additional concern of forward air controllers is the avoidance of harm to noncombatants in the strike area.
Early air ground support efforts
As close air support began during World War I, there were pioneer attempts to direct the trench strafing by the ground troops marking their positions by laying out signal panels on the ground, firing flares, or lighting smoke signals. Aircrews had difficulty communicating with the ground troops; they would drop messages or use messenger pigeons. Benno Fiala von Fernbrugg, an Austro-Hungarian pilot, pioneered the use of radio for fire control; at the Battle of Gorlice he used a radio transmitter in his airplane to send changes via morse code to an artillery battery on the ground. Colonel Billy Mitchell also equipped his Spad XVI command airplane with a radio, and the Germans experimented with radios in their Junkers J.I all-metal-structure, armored-fuselage sesquiplanes.The Marines in the so-called Banana wars of the 1920s and 1930s used Curtiss Falcons and Vought Corsairs that were equipped with radios powered by airstream-driven generators, with a range of up to 50 miles. Another method of communication was for the pilot to drop messages in a weighted container, and to swoop in and pick up messages hung out by ground troops on a "clothesline" between poles. The objective was aerial reconnaissance and air attack. Using these various methods, the Marine pilots combined the functions of both FAC and strike aircraft, as they carried out their own air attacks on the Sandinistas in Nicaragua in 1927. The commonality of pilots and ground troops belonging to the same service led to a close air support role similar to that sought by use of FACs, without the actual use of a FAC. On 27 October 1927, a Marine patrol used cloth panels to direct an air strike—arguably the first forward air control mission. This distinctive U.S. Marine doctrine of interaction between Marine infantry and aviation would persist, recurring in the Korean War and the Vietnam War.
French colonial operations in the Rif War from 1920–1926 used air power similarly to the Marines in Nicaragua against the Sandinistas but in a different environment, the desert. The French Mobile Groups of combined arms not only used aircraft for scouting and air attack; the airplanes carried trained artillery officers as observers. These aerial observers called in artillery fire via radio.
The German military noted close air support operations in the Spanish Civil War and decided to develop its forward air control capability. By 1939, they had forward air control teams called Ground Attack Teams attached to every headquarters from regiment level upwards. These Teams directed air strikes flown by Luftwaffe close air support units. Extensive coordinated training by air and ground troops had raised this system to state of the art by the beginning of World War II.
When the United States Army Air Forces was founded on 20 June 1941, it included provisions for Air Ground Control Parties to serve with the United States Army at the division, corps, and Army headquarters. The Air Ground Control Parties functions were to regulate bombing and artillery in close conjunction with the ground troops, as well as assess bomb damage. They were thus the first of similar units to try to fulfill the functions of the FAC without being airborne. However, these units were often plagued by turf wars and cumbersome communications between the respective armies and air forces involved. As a result, it could take hours for an air strike requested by ground troops to actually show up.
World War II
However, forward air control during World War II came into existence as a result of exigency, and was used in several theaters of World War II. Its reincarnation in action was a result of field expedience rather than planned operations.On the Allied side, British forces in the North Africa campaign began using the Forward Air Support Links, a "tentacle" system that used radio links from front line units to the rear. Air force teams were co-located with the army command. Close air support would be requested by forward units and if approved delivered from "cab ranks" of fighter-bombers held near the front lines. The requesting unit would direct the air strikes. The U.S. Army would not copy the British system until the Allied invasion of Italy, but adapted it for use there and in France after the Invasion of Normandy of 6 June 1944.
In the Pacific Theater, 4 Squadron of the Royal Australian Air Force began forward air control at the Battle of Buna-Gona, New Guinea in November 1942. The RAAF continued forward air control in the Pacific for the rest of the war. By November 1943, the U.S. Marines were using forward air control during the Battle of Bougainville.
The United States would end World War II still without an air control doctrine. When the U.S. Air Force split from the U.S. Army in 1947, neither took on the responsibility for forward air control; the U.S. military thus had no functional forward air control when the Korean War broke out.
Post World War II
British Commonwealth operations
The United Kingdom and Commonwealth continued to build on their experience in the Second World War in various campaigns around the world in the second half of the twentieth century, including the Malayan Emergency, the Suez Crisis, the Indonesian Confrontation and operations in Aden and Oman. With the re-formation of the Army Air Corps in 1957 this new corps's functions included airborne forward air control.Korean War
Although the United States, as part of the United Nations Command in the Korean War, entered the war on 26 June 1950 with no forward air controllers, it rapidly improvised close air support procedures for UNC forces. By 20 July, jury-rigged systems were not only controlling air strikes against the communist foe, but also occasionally directing aerial interceptions of opposing aircraft. Both the U.S. high command and North Korean General Nam Il agreed that only tactical air power saved United Nation forces from defeat during the mobile warfare stage of the war.When the front lines bogged down into static trench warfare in Summer 1951, forward air control diminished in importance. To cope with the communist switch to night operations, both radar and Shoran bombing techniques were developed. However, close air support continued, and sometimes used to direct interdiction missions against the communist lines of communications. By this time, Allied air forces were contributing a considerable portion of the tactical air strikes.
By the cessation of hostilities, airborne forward air controllers alone were credited with flying 40,354 forward air control sorties, and directing air strikes that killed an estimated 184,808 communist troops. At times, tactical air was credited with inflicting about half of all communist casualties.
Despite having agreed on a common forward air control doctrine as embodied in Field Manual 31 - 35 Air-Ground Operations, a turf war over doctrine raged between the U.S. Air Force and the U.S. Army for the entire war. Additionally, the U.S. Marine Corps maintained its own FAC operation during the war. Also, U.S. Navy carrier aviation would not completely coordinate its operations with the Air Force/Army system until the final month of the war. With no common doctrine agreed upon during the war, forward air control systems were shut down postwar in 1956.
Vietnam War
Forward air controllers played a major part in the largest bombing campaign in history during the Vietnam War. While World War II had featured indiscriminate mass air raids on major cities worldwide, bombing during the Vietnam War was aimed at smaller targets in a country the size of New Mexico. Unless bombs were dropped in a free fire zone, or on a pre-briefed target, the bombing in Vietnam was directed by FACs. Also unlike World War II, serious efforts were made to avoid hitting the civilian populace, which also called for FAC intervention.Reinvention of forward air control
In 1961, when forward air control was revived, it promptly ran into the recurring problems of unreliable radios, a shortage of supplies, lack of suitable aircraft, differing concepts of close air support, and unfavorable terrain.The first manning requirement for FACs, levied in 1962, amounted to 32 slots in Vietnam. Even as the slots slowly filled, the requirement proved inadequate. The 19th Tactical Air Support Squadron was then assigned in-country in mid-1963 to augment the FAC force. By January 1965, there were still only 144 USAF FACs in Southeast Asia. While the U.S. Air Force would continue to add more FACs, projecting a need for 831 FACs, and stationing four more Tactical Air Support Squadrons in Southeast Asia by April 1965, the manning levels of assigned FACs would run about 70% of need until December 1969. Other branches of the U.S. military also had FACs; the U.S. Army had at least two aviation companies of FACs, the U.S. Marine Corps had an organic FAC squadron within its forces, and the U.S. Navy established its own FAC squadron in the Mekong Delta. U.S. involvement had begun with a South Vietnamese FAC training program; later in the war, Laotians and Hmong were also trained as FACs.