Overview
The Republic XF-12 Rainbow was an American four-engine, all-metal prototype aircraft designed by Republic Aviation in the 1940s for aerial reconnaissance with the United States Army Air Forces (USAAF). Designed to maximize aerodynamic efficiency, the XF-12 was referred to as "flying on all fours" meaning: four radial engines, 400 mph (640 km/h) cruise, 4,000 mi (6,400 km) range, at 40,000 ft (12,000 m). The aircraft was redesignated as the XR-12 when the USAAF became the United States Air Force in 1947.
Specifications
Figures are compiled from public sources and may be approximate; they can vary by variant and configuration.
Photos
Photo 1: San Diego Air & Space Museum Archives / Wikimedia Commons · Public domain
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