The Fairchild Republic A-10 Thunderbolt II is an American single-seat, twin-engine, straight-wing jet aircraft developed by Fairchild-Republic in the early 1970s. The A-10 was designed for a United States Air Force (USAF) requirement to provide close air support (CAS) for ground forces by attacking tanks and other armored vehicles, and other ground targets with a limited air defense capability. It was the first USAF aircraft designed solely for CAS.
The A-10 was designed around the GAU-8 Avenger, a heavy rotary cannon that forms the aircraft's primary armament. (It is, to date, the heaviest rotary cannon ever mounted on an aircraft.) The aircraft's hull incorporates over 1,200 pounds (540 kg) of armor and was designed with survivability as a priority, with protective measures in place which enable the aircraft to continue flying even after taking significant damage.
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. The A-10 is more commonly known by its nickname "Warthog" or simply "Hog". 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. The A-10 is not expected to be replaced until 2028 or later.