The Douglas XP3D was a prototype

American American(s) may refer to: * American, something of, from, or related to the United States of America, commonly known as the "United States" or "America" ** Americans, citizens and nationals of the United States of America ** American ancestry, p ...

patrol

flying boat A flying boat is a type of seaplane with a hull, allowing it to land on water. It differs from a floatplane in having a fuselage that is purpose-designed for flotation, while floatplanes rely on fuselage-mounted floats for buoyancy. Though ...

of the 1930s. A twin-engined high-winged

monoplane A monoplane is a fixed-wing aircraft configuration with a single mainplane, in contrast to a biplane or other types of multiplanes, which have multiple wings. A monoplane has inherently the highest efficiency and lowest drag of any wing con ...

, the P3D was produced by the

Douglas Aircraft Company The Douglas Aircraft Company was an American aerospace manufacturer, aerospace and military, defense company based in Southern California. Founded in 1921 by Donald Wills Douglas Sr., it merged with McDonnell Aircraft in 1967 to form McDonnell D ...

to equip the

US Navy The United States Navy (USN) is the naval warfare, maritime military branch, service branch of the United States Department of Defense. It is the world's most powerful navy with the largest Displacement (ship), displacement, at 4.5 millio ...

's Patrol squadrons, but despite meeting the Navy's requirements, the rival

Consolidated PBY The Consolidated Model 28, more commonly known as the PBY Catalina (U.S. Navy designation), is a flying boat and amphibious aircraft designed by Consolidated Aircraft in the 1930s and 1940s. In U.S. Army service, it was designated as the OA ...

was preferred owing to a lower price.

Development and design

In 1933, the

United States Navy The United States Navy (USN) is the naval warfare, maritime military branch, service branch of the United States Department of Defense. It is the world's most powerful navy with the largest Displacement (ship), displacement, at 4.5 millio ...

placed orders with both Douglas and

Consolidated Aircraft The Consolidated Aircraft Corporation was founded in 1923 in aviation, 1923 by Reuben H. Fleet in Buffalo, New York, the result of the Gallaudet Aircraft Company's liquidation and Fleet's purchase of designs from the Dayton-Wright Company as the ...

for single prototypes of patrol flying boats, to replace the

Consolidated P2Y The Consolidated P2Y was an American sesquiplane maritime patrol flying boat. The aircraft was also made by Martin as the P3M, as a parasol monoplane, due to the Navy awarding production contracts separately from prototype contracts. Develop ...

and Martin P3M that equipped the Navy's patrol squadrons.Swanborough and Bowers 1976, p.80. Douglas's design, the P3D, was designed in parallel with the smaller YB-11 being developed for the

United States Army Air Corps The United States Army Air Corps (USAAC) was the aerial warfare service component of the United States Army between 1926 and 1941. After World War I, as early aviation became an increasingly important part of modern warfare, a philosophical ri ...

(which was eventually built as the YOA-5), and like the YB-11, was a twin-engined high-winged

with its engines (the new

Pratt & Whitney R-1830 The Pratt & Whitney R-1830 Twin Wasp is an American air-cooled radial aircraft engine. It has 14 cylinders, arranged in two rings of seven. It displaces and its bore and stroke are both . The design traces its history to 1929 experiments a ...

Twin Wasp

radial engine The radial engine is a reciprocating engine, reciprocating type internal combustion engine, internal combustion engine configuration in which the cylinder (engine), cylinders "radiate" outward from a central crankcase like the spokes of a wheel. ...

mounted in nacelles above and ahead of the wing. Unlike the YB-11, it was a pure flying boat rather than an

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, and was therefore fitted with retractable beaching gear to allow it to be moved to and from shore, rather than a full undercarriage allowing operation from land or sea.Francillon 1979, p.194. The Douglas prototype, designated XP3D-1, first flew on 6 February 1935, and was delivered to

NAS San Diego Naval Air Station North Island or NAS North Island , at the north end of the Coronado peninsula on San Diego Bay in San Diego, California, is part of the largest aerospace-industrial complex in the United States Navy – Naval Base Coronado (N ...

for testing in March 1935. Both the XP3D-1 and Consolidated's P3Y successfully passed the Navy's performance tests,Creed 1986, pp.32–33. demonstrated very similar performance, an order was placed for 60 P3Ys (re-designated PBY in May 1936) because the Consolidated aircraft was cheaper, costing $90,000 per aircraft compared with $110,000 for the Douglas aircraft.Francillon 1979, pp.194–195. Douglas re-designed the P3D to improve performance in order to win follow-on contracts, and rebuilt the XP3D-1, raising the wing by 27 inches (0.69 m) and mounting the engines on the leading edge of the wing. The fixed wing floats were replaced by retractable floats, and a nose turret was fitted. The rebuilt aircraft, designated XP3D-2 was re-delivered on 15 May 1935, but production orders again went to Consolidated, for the improved PBY-2.Francillon 1979, p.195.

Operational history

The XP3D-1 was briefly operated by Patrol Squadron 3 (

VP-3 VP-3 was a Patrol Squadron of the U.S. Navy. The squadron was established as Patrol Squadron 16-F (VP-16F) on 2 January 1937, redesignated Patrol Squadron 16 (VP-16) on 1 October 1937, redesignated Patrol Squadron 41 (VP-41) on 1 July 1939, re ...

) until it was returned to Douglas for re-building. The re-built XP3D-2 was used by VP-11F as an VIP aircraft until destroyed in a crash at

Acapulco Bay Acapulco de Juárez (), commonly called Acapulco ( , ; ), is a city and major seaport in the state of Guerrero on the Pacific Coast of Mexico, south of Mexico City. Located on a deep, semicircular bay, Acapulco has been a port since the ear ...

Mexico Mexico, officially the United Mexican States, is a country in North America. It is the northernmost country in Latin America, and borders the United States to the north, and Guatemala and Belize to the southeast; while having maritime boundar ...

on 8 February 1937. The crash was survived by the embarked VIP, Rear Admiral

Ernest King Ernest Joseph King (23 November 1878 – 25 June 1956) was a Fleet admiral (United States), fleet admiral in the United States Navy who served as Commander in Chief, United States Fleet (COMINCH) and Chief of Naval Operations (CNO) during Worl ...

Variants

;XP3D-1 :Prototype aircraft. Two 825 hp (615 kW) R-1830-58 engines. ;XP3D-2 :Rebuilt XP3D-1, with raised wing, engines moved to wing leading edge and retractable wing floats. Two 900 hp (671 kW) R-1830-64 engines.

Operators

; *

Specifications (XP3D-2)

References

;Notes ;Bibliography *Creed, Roscoe. ''PBY: The Catalina Flying Boat''. Shrewsbury, UK:Airlife Publishing, 1986. . *Francillon, René J. ''McDonnell Douglas Aircraft since 1920''. London:Putnam, 1979. . *Swanborough, Gordon and Peter M. Bowers. ''United States Navy Aircraft since 1911''. London:Putnam, 1976. . *Wagner, Ray, ''American Combat Planes'', Doubleday & Company, Garden City, New York, 1982,

External links

1000Aircraftphotos

''Time'', March 25, 1935. {{USN patrol aircraft Flying boats 1930s United States patrol aircraft High-wing aircraft P3D Aircraft first flown in 1935 Twin piston-engined tractor aircraft