Air interdiction

Air interdiction (AI), also known as deep air support (DAS), is the use of preventive aircraft attacks against enemy targets, that are not an immediate threat, in order to delay, disrupt, or hinder later enemy engagement of friendly forces. It is a core capability of virtually all military air forces, and has been conducted in conflicts since World War I.

A distinction is often made between tactical and strategic air interdiction, depending on the objectives of the operation. Typical objectives in tactical interdiction are meant to affect events rapidly and locally, for example through direct destruction of forces or supplies en route to the active battle area. While strategic objectives are often broader and more long-term, with less direct attacks on enemy fighting capabilities, instead focusing on infrastructure, logistics and other supportive assets.

The term deep air support, relates to close air support and denotes the difference between their respective objectives. Close air support, as the name suggests, is directed towards targets close to friendly ground units, as closely coordinated air-strikes, in direct support of active engagement with the enemy. Deep air support or air interdiction is carried out further from the active fighting, based more on strategic planning and less directly coordinated with ground units. Despite being more strategic than close air support, air interdiction should not be confused with strategic bombing, which is unrelated to ground operations.

With air interdiction in World War I, the goal was to isolate the battlefield by strafing and bombing enemy supply lines. Favorite targets were railroad lines, bridges, and truck convoys. Due to the primitive state of aircraft and weapons technology, as well as the undeveloped nature of air doctrine and tactics, air interdiction missions in World War I were of limited utility.

The potential of air interdiction was clearly recognized, however, and during World War II it once again became a major mission of air forces. Although air interdiction operations were conducted in all theaters, the most extensive and thoroughly analyzed, particularly in the English language, were those of the United States and United Kingdom against the Axis. Specifically, the Allies launched major air interdiction efforts in the North African, Italian, and Normandy campaigns. The venues for these three campaigns were markedly different in terms of weather, terrain, the enemy’s supply and transportation infrastructure, and the availability of intelligence regarding the enemy. As a consequence of these differences, the results of air interdiction also varied. The greatest success was in the desert terrain of North Africa, where Axis forces also relied heavily on vulnerable and visible sea convoys across the Mediterranean Sea. The Italian campaign, by contrast, was characterized by mountainous terrain, poor weather conditions, and shortened German supply lines. The diverse results of these two campaigns taught air planners differing lessons.

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Wikipedia