The Curtiss-Wright XP-55 Ascender (company designation CW-24) is a 1940s United States prototype fighter aircraft built by Curtiss-Wright. Along with the Vultee XP-54 and Northrop XP-56, it resulted from United States Army Air Corps proposal R-40C issued on 27 November 1939 for aircraft with improved performance, armament, and pilot visibility over existing fighters; it specifically allowed for unconventional aircraft designs. An unusual design for its time, it had a canard configuration, a rear-mounted engine, swept wings, and two vertical tails. Because of its pusher design, it was sarcastically referred to as the "Ass-ender". Like the XP-54, the Ascender was designed for the Pratt & Whitney X-1800 engine, but was re-designed after that engine project was canceled. It was also the first Curtiss fighter aircraft to use tricycle landing gear. Design and development June 1940, the Curtiss-Wright company received an Army contract for preliminary engineering data and a powered wind tunnel model. The designation P-55 was reserved for the project. The USAAC was dissatisfied with the results of these tests. Accordingly, Curtiss-Wright built a flying full-scale model they designated CW-24B. The flying testbed was powered by a Menasco C68-5 inline engine. It had a fabric-covered, welded steel tube fuselage with a wooden wing. The undercarriage was non-retractable. July 1942, the United States Army Air Forces issued a contract for three prototypes under the designation XP-55. Serial numbers were 42-78845 through 42-78847. During this time, the Pratt & Whitney X-1800 H-block sleeve valve engine was delayed, and was eventually canceled. Curtiss decided to switch to the Allison V-1710 (F16) liquid-cooled inline engine because of its proven reliability. Armament was to be two cannon and two machine guns. During the mock-up phase, engineers switched to the V-1710-95. The 20 mm cannons were also replaced by 0.50 in machine guns. One feature of the XP-55 was a propeller jettison lever inside the cockpit to prevent the pilot from hitting the propeller during bailout. The jettison device was invented by W. Jerome Peterson while working as a design engineer for Curtiss-Wright. Operational history The first XP-55 (42-78845) was completed on 13 July 1943 with the same configuration as the final prototype CW-24B. The aircraft made its first flight on 19 July 1943 from the Army's Scott Field near the Curtiss-Wright plant in St Louis, Missouri. The pilot was J. Harvey Gray, Curtiss' test pilot. Testing revealed the takeoff run was excessively long. To solve this