Forward air control

Forward air control is the provision of guidance to close air support (CAS) 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 (FAC). A primary forward air control function is ensuring the safety of friendly troops during close air support. Enemy targets in the front line ("Forward Edge of the Battle Area" in US terminology) 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 (FACs) 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. 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.