Originally conceived as a counter-insurgency aircraft to help the US war effort in Southeast Asia, the A-10 emerged as a dedicated close air support aircraft with the primary role of destroying enemy armour. The A-10 was built around the 30-mm GAU-8 Avenger cannon, the most powerful gun ever flown. The A-10 was also required to carry large numbers of ground-attack stores and be survivable in the face of intense battlefield anti-aircraft fire.
Unpressurised and without radar, the A-10A remains austerely equipped in terms of avionics, but is a very hard-hitting and well-protected machine. The cockpit is protected from 23-mm cannon hits by a bath of titanium armour. The nickname of Warthog has largely stuck on account of the type's ungainly looks. However, the unconventional design is central to its ability to survive the lethal battlefield environment; the fuel-efficient turbofans of low IR signature are mounted above the rear fuselage and the A-10 can remain airworthy with an engine, tail or other parts inoperative or shot away.
The A-10A first flew in production form on 21 October 1975 and entered USAF service in 1977. Much derided and destined for premature retirement prior to the 1991 Gulf War, the star performance of the A-10A and its identical, but Forward Air Control (FAC)-roled, OA-10A variant led to the type's continued leading presence in the USAF's front-line. Most current aircraft have received the LASTE modification which adds an autopilot and also considerably improves gun accuracy.
Primarily armed with AGM-65 Maverick missiles in addition to the 30-mm gun, the A-10 has been a key player in subsequent USAF actions, including combat over the former Yugoslavia. Although a plan to supply second-hand A-10As to Turkey was aborted, the type will remain in US service well into the 21st century. The type currently equips nine active-duty, three AFRES and six ANG units.