High Quality Content by WIKIPEDIA articles! Vultee XP-68 Tornado was proposed American high-altitude interceptor aircraft. It was based on the XP-54 Swoose Goose powered by the Wright R-2160 Tornado 42-cylinder radial engine driving a set of contra-rotating propellers. When the engine was canceled, on 22 November 1941, the XP-68 was also canceled. The XP-54 was an American prototype fighter built by the Vultee Aircraft Company. Vultee had submitted a proposal in response to a U.S. Army Air Corps request for an unusual configuration. The Vultee design won the competition, beating the Curtiss XP-55 Ascender and the Northrop XP-56 Black Bullet. Vultee designated it Model 84, a descendant of their earlier Model 78. After completing preliminary engineering and wind tunnel tests, a contract for a prototype was awarded on 8 January 1941.