Republic Rainbow

Republic Rainbow			Photo Gallery
The Republic XF-12 was a reconnaissance aircraft designed for high-speed overflights over Japan. The original requirements were an airspeed of 400 mph, range of 4,000 miles and a ceiling of 40,000 ft. Its primary objective was high-speed overflights of the Japanese homeland. Powered by four Pratt & Whitney R-4360 engines, on 4 February 1946 it reached an altitude of 45,000 ft., at 470 mph and demonstrated a range of 4,500 miles, exceeding design criteria. The XF-12 was the fastest aircraft of its day to use four reciprocating engines, and the only one to exceed 450 mph in level flight. Only two prototypes were built as the requirement evaporated after World War II. An airliner variant was proposed, as the RC-2 Rainbow, but was deemed uneconomical and cancelled before being built. It was retired in June 1952.