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 Cycloneradial engines mounted in individual nacelles above the wing, resembling an enlarged version of the
Douglas Dolphin.[1]
Prior to completion, it was redesignated firstly as an observation aircraft YO-44 and then as the YOA-5 'observation amphibian model 5'.[2] It first flew during January 1935, and was delivered to the army during February that year.[1] 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.[3]
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 930 hp (690 kW)
Wright YR-1820-45 Cyclone engines for experimental long-range flying, then re-engined again with 750 hp (560 kW)
Wright R-1820-25 Cyclones.
Specifications (YOA-5)
Data from McDonnell Douglas aircraft since 1920 : Volume I[4]
General characteristics
Crew: 4
Length: 69 ft 6 in (21.18 m)
Wingspan: 89 ft 9 in (27.36 m)
Height: 212 ft 0 in (64.62 m)
Gross weight: 20,000 lb (9,072 kg)
Powerplant: 2 ×
Wright R-1820-25 Cyclone 9-cylinder air-cooled radial piston engines, 750 hp (560 kW) each
Performance
Maximum speed: 169 mph (272 km/h, 147 kn) at sea level