An A-10 Thunderbolt II aircraft, left, and KC-135 Stratotanker aircraft participate in an icing test while a T-38 Talon aircraft, top, acts as a photo chase plane

The A-10 Thunderbolt has excellent maneuverability at low airspeeds and altitude and is a highly accurate and survivable weapons-delivery platform. Called the “Warthog” for its aggressive look and often painted with teeth on the nose cone, the A-10 Thunderbolt II is the U.S. Air Force’s primary low-altitude close air support aircraft best known for its GAU-8 Avenger 30mm Gatling gun designed to fire armor-piercing depleted uranium and high explosive incendiary rounds. In the 1970s the threat of Soviet armored forces and all-weather attack operations had become more serious. Six companies submitted aircraft proposals, with Northrop and Fairchild-Republic selected to build prototypes: the YA-9A and YA-10A, respectively. General Electric and Philco-Ford were selected to build and test GAU-8 cannon prototypes. First A-10 was delivered to the U.S. Air Force on 30 March 1976. By 1984, 715 airplanes had been built.