The Fairchild Republic A-10A Thunderbolt II is a single-seat close air support aircraft named after the P-47 Thunderbolt of World War II, though pilots and ground crew know it better as the Warthog. It was the first U.S. Air Force aircraft designed specifically for close air support of ground forces and entered service in 1976. The A-10 is simple, survivable, and effective, able to operate from rough forward airstrips close to battle areas. Many parts are interchangeable from left to right, including the engines, main landing gear, and vertical stabilizers. Its cockpit and gun area are protected by one and a half inch thick titanium armor capable of withstanding direct hits from a 23mm projectile, and its engines are positioned so the tail surfaces help mask exhaust from ground-launched heat-seeking missiles. The aircraft is designed to keep flying even with one half of a wing or a vertical stabilizer shot away, and its straight wing makes it highly maneuverable at low speeds and altitudes for accurate weapons delivery. It can carry up to 16,000 pounds of bombs and missiles on eleven pylons and 1,350 rounds of ammunition for its 30mm cannon. The Warner Robins Air Logistics Center is responsible for logistic support and depot-level repair of the gun, avionics, electronic warfare and communication systems, and air-launched missiles used on the A-10. The A-10 on display, serial number 75-0305, was the fifty-fifth production Warthog built; after its acceptance by the Air Force in July 1977, it served with units at Myrtle Beach AFB, South Carolina, and Davis-Monthan AFB, Arizona, then in 1992 was assigned to Eielson AFB, Alaska, where it was known as Arctic Hawg and served as a ground weapons trainer until October 2007. The A-10 is also known for its GAU-8 Avenger, a 30mm hydraulically driven seven-barrel Gatling-type rotary cannon that can fire sixty-five rounds per second; designed as an anti-tank weapon, it fires an armor-piercing round with a high-density depleted uranium core capable of penetrating over 2.75 inches of armor plate, and the gun system weighs over 4,000 pounds.