Offensive counter air

Offensive Counter-Air (OCA) is a military term for the suppression of an enemy's military air power by destroying or disabling the aircraft&mdash;preferably on the ground. This includes disablement achieved by damaging the infrastructure (for example runways) or logistics.

Tactics
Operations include attacks on air bases. Aircraft on air bases are often more concentrated and vulnerable than they are in flight, and destroying them at their bases may be much easier than destroying them in aerial combat. Attacks on bases crowded with aircraft can have devastating results in the struggle for control of the air. Since the Six-Day War in June 1967 where Israel destroyed much of Egypt's air force on the ground, most air forces have provided protection, such as Hardened Aircraft Shelters for their aircraft to prevent wholesale destruction of their aircraft. Even if the attacker does not catch air forces on the ground, destruction of critical base facilities can still be decisive. When air bases cannot provide landing, launching, or critical support (e.g., maintenance, fuel, munitions), air forces are effectively grounded.

Air-to-air operations conducted by fighter aircraft are also offensive counter air measures, but they are seen as a comparatively slow way of achieving the final objective - air superiority.

World War II
Offensive counter-air strikes have been used since World War I, and the German attacks against allied airfields during World War II in 1945 was a particularly successful example. The Teishin Shudan and Giretsu Kuteitai carried out two OCA raids in the Pacific theatre against B29s. In one measure the most successful single OCA mission to date was Operation Focus, the Israeli offensive that opened the Six Day War of 1967, when the Heyl Ha'avir destroyed a large portion of the air power of Egypt, Syria, and Jordan, mostly on the ground, totaling roughly 600 airframes destroyed by a force of 200 aircraft. However, in sheer number of planes destroyed, the opening two weeks of Operation Barbarossa saw some 3-4,000 Russian planes destroyed in total. Other successful attacks include US counter air operations in Korea in 1950 and 1953, French and British attacks during the Suez Crisis and many others. However, there have also been notable failures like Operation Chengiz Khan initiated by Pakistan during the Indo-Pakistani War of 1971 and Iraqi attacks on Iran.

The Teishin Shudan and Giretsu Kuteitai commandos carried out two notable OCA raids during World War II. The Vietcong destroyed a number of planes through mortars, and recently a Marine aviation unit was overrun in Afghanistan.

Cold War
During the 1950s, the Cold War strategy of both NATO and the Warsaw Pact called for OCA to be carried out with tactical nuclear weapons, but by the mid-1960s, new policies of 'proportional response' brought about a return to conventional tactics. Beginning shortly before the Six Day War, specialized weapons were developed for disrupting runways, such as the BLU-107 Durandal anti-runway bomb. Various such weapons continue to be fielded, notably the Hunting JP233 munition used by RAF Panavia Tornado aircraft during the 1991 Gulf War.

Although OCA missions are often carried out via air strikes, they are not limited to aerial action. As a common rubric of the Cold War held, a tank parked in the middle of an enemy runway is a perfectly valid counter-air weapon.