The Curtiss P-40 was an American single-engine, single- seat, low-wing, all-metal fighter and ground attack aircraft that was used extensively in World War II. It was a direct adaptation of the P-36 Hawk to enable mass production of front line fighters without significant development time. By the time the last plane rolled off the production line in November 1944, a total of 13,738 P-40s had been manufactured. First flown in 1938, the P-40 has been operated by the air forces of 28 countries. The United States Army Air Corps made Warhawk the official name of all P- 40s in the US. British Commonwealth air forces gave the names Tomahawk and Kittyhawk to different variants.