The XP-67 project started out as an unconventional design submitted under the 1939 Army Air Corps Proposal R-40C, which also resulted in the XP-54, XP-55 and XP-56 designs.
After two re-designs ordered by the AAF, McDonnell was awarded a construction contract for two aircraft on May 22, 1941. The first aircraft (S/N 42-11677) was completed in December 1943 and featured a sleek aerodynamic profile. The exhaust gases from the turbo-supercharged Continental engines were used as a jet-assist to increase performance; however, the rated horsepower of the "Hyper" engines was not achieved and the aircraft fell short of performance estimates.
The aircraft was destroyed in a fire on Sept. 6, 1944, and the project was canceled before the second aircraft was built.
TECHNICAL NOTES: Armament: None; designed for four 37mm cannon Engines: Two turbo-supercharged Continental XI-1430-17/19s of 1,350 rated hp each (approximately 1,050 hp actual) Maximum speed: 405 mph Cruising speed: 210 mph Range: 2,000 mi. Service ceiling: 37,000 ft. Span: 55 ft. 0 in. Length: 42 ft. 0 in. Height: 14 ft. 9 in. Weight: 17,745 lbs. empty/23,910 lbs. gross Crew: One