The Douglas YOA-5 was an Amphibious aircraft designed for the United States Army Air Corps. Although a prototype was built, it did not enter production. Design and development In November 1932, the U.S. Army ordered the development of an amphibious reconnaissance aircraft/bomber, intended to act as navigation leaders and rescue aircraft for formations of conventional bombers. The resultant aircraft, which was ordered under the bomber designation YB-11, was designed in parallel with the similar but larger Douglas XP3D patrol flying boat for the United States Navy. It was a high-winged monoplane with two Wright R-1820 Cyclone radial engines mounted in individual nacelles above the wing, resembling an enlarged version of the Douglas Dolphin. Prior to completion, it was redesignated firstly as an observation aircraft YO-44 and then as the YOA-5 'observation amphibian model 5'. It first flew during January 1935, and was delivered to the army during February that year. The concept for which it was designed proved impracticable, and no further production ensued, but the YOA-5 was used to set two world distance records for amphibians, being finally scrapped in December 1943. Operators United States Army Air Corps Variants YB-11 An amphibious reconnaissance bomber ordered in 1932 by the US Army Air Corps, powered by 2x Wright R-1820-13 Cyclone radial engines. YO-44 The YB-11 redesignated in the Observation category before completion. YOA-5 Another redesignation to the Observation Amphibian category. One built, given the aforementioned designations at various times in its life. The YOA-5 started life with Wright R-1820-13 Cyclone engines, was re-engined with Wright YR-1820-45 Cyclone engines for experimental long-range flying, then re-engined again with Wright R-1820-25 Cyclones. Specifications (YOA-5) See also References Bibliography Francillon, René. McDonnell Douglas Aircraft since 1920. London:Putnam, 1979. . External links USAF Museum description of YB-11 Encyclopedia of American aircraft OA-5 Douglas B-11 High-wing aircraft Amphibious aircraft Aircraft first flown in 1935 Twin piston-engined tractor aircraft