Developed for the United States Army Air Corps (USAAC), the Seversky XP-41 was a single-seat fighter aircraft. The last production Seversky P-35 was modified by adding a new streamlined canopy, a Pratt & Whitney R-1830-19 engine with a two-speed supercharger, and revised landing gear. First flying in March 1939 it was developed in parallel with the P-43 Lancer, and work was stopped when the USAAC showed a preference for the latter.
Originally designed as a dive-bomber, the role of the Vultee XA-41 was changed to a low level attack aircraft when the USAAF decided that dive bombers were too vulnerable. Changing priorities and the coming end of the Second World War saw the order for two prototypes changed to just one.
The only prototype first flew on 11 February 1944. It was used predominantly as an engine test bed for the R-4360, although the US Navy evaluated it against other attack aircraft (Douglas AD-1 Skyraider and Martin AM-1 Mauler). Engine tests continued until 1950 when the XA-41 was scrapped.
The Hughes XF-11 was a prototype reconnaissance aircraft designed for the United States Army Air Forces (USAAF). Although 100 aircraft were ordered in 1943, the program was delayed beyond the end of the Second World War, rendering it surplus to the USAAF needs and it was cancelled.
The first of two prototypes (serial number 44-70155) crashed on its first flight on 7 July 1946, piloted by Howard Hughes who was critically injured. The second prototype (44-70156) first flew on 5 April 1947 again piloted by Hughes. This time without incident.
The United States Air Force (USAF) was created as a separate service in September 1947, and the XF-11 was redesignated as the XR-11 in July 1948. The XR-11 continued to fly until mid 1949, after which is was used as an instructional airframe for several months before being scrapped in November.
