Douglas YOA-5


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.

Parked Douglas YB-11.jpg
Role Seaplane bomber
Manufacturer Douglas Aircraft Company
First flight 1935
Introduction 1935
Retired 1943
Status Prototype
Primary user United States Army Air Corps
Number built 1
Developed from Douglas XP3D

Design and developmentEdit

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.[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]


  United States


An amphibious reconnaissance bomber ordered in 1932 by the US Army Air Corps, powered by 2x Wright R-1820-13 Cyclone radial engines.
The YB-11 redesignated in the Observation category before completion.
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)Edit

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


  • Maximum speed: 169 mph (272 km/h, 147 kn) at sea level
  • Power/mass: 0.075 hp/lb (0.123 kW/kg)


  • Guns: 3× .30 in (7.62 mm) machine guns in open bow and fuselage positions

See alsoEdit

Related lists


  1. ^ a b Francillon 1979, p.192.
  2. ^ Wagner, Ray, American Combat Planes, 1981, Doubleday & Company, Garden City, New York, ISBN 9780385131209, page 307
  3. ^ Francillon 1979, pp. 192–193.
  4. ^ Francillon, René J. (1988). McDonnell Douglas aircraft since 1920 : Volume I. London: Naval Institute Press. pp. 184–193. ISBN 0870214284.


  • Francillon, René. McDonnell Douglas Aircraft since 1920. London:Putnam, 1979. ISBN 0-370-00050-1.

External linksEdit

  • USAF Museum description of YB-11
  • Encyclopedia of American aircraft