A-10 Thunderbolt II

The A-10 Thunderbolt II is an American single-seat, twin-engine, straight-wing jet aircraft developed by Fairchild-Republic for the United States Air Force to provide close air support (CAS) of ground forces by attacking tanks, armored vehicles, and other ground targets, with a limited air interdiction capability. It is the first U.S. Air Force aircraft designed exclusively for close air support.

The A-10's official name comes from the Republic P-47 Thunderbolt of World War II, a fighter that was particularly effective at close air support. However, the A-10 is more commonly known by its nickname "Warthog" or simply "Hog".^[3] As a secondary mission, it provides airborne forward air control, guiding other aircraft against ground targets. A-10s used primarily in this role are designated OA-10.

Criticism that the U.S. Air Force did not take close air support seriously prompted a few service members to seek a specialized attack aircraft.^[5] In the Vietnam War, large numbers of ground-attack aircraft were shot down by small arms, surface-to-air missiles, and low-level anti-aircraft gunfire, prompting the development of an aircraft better able to survive such weapons. In addition, the UH-1 Iroquois and AH-1 Cobra helicopters of the day, which USAF commanders had said should handle close air support, were ill-suited for use against armor, carrying only anti-personnel machine guns and unguided rockets meant for soft targets. The F-4 Phantom II was pressed into close air support, but usually in emergencies, as its high cruising speed and fuel consumption hindered its ability to loiter. The lack of a gun on most F-4 variants, coupled with the relative ineffectiveness of the standard 20 mm round on M61 Vulcan-equipped F-4Es against hard targets, made strafing runs either impossible or ineffective.