__NOTOC__ The Donnet-Denhaut flying boat was a maritime patrol and anti-submarine warfare aircraft produced in France during the First World War. Known at the time simply as "Donnet-Denhaut" or "DD" flying boats, the DD-2, DD-8, DD-9, and DD-10 designations were applied retrospectively to denote the various changes in configuration made during their service life.

Design and development

Developed in response to a French Navy requirement, these were

biplane A biplane is a fixed-wing aircraft with two main wings stacked one above the other. The first powered, controlled aeroplane to fly, the Wright Flyer, used a biplane wing arrangement, as did many aircraft in the early years of aviation. While ...

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s of conventional configuration with two-bay unstaggered wings, and a Salmson R9 160 hp radial engine, mounted pusher-fashion on struts in the interplane gap. The French Navy ordered some 90 aircraft in this original configuration (later dubbed DD-2), and in 1917, requested Donnet-Denhaut to redesign the aircraft to take advantage of the new

Hispano-Suiza 8 The Hispano-Suiza 8 was a water-cooled V8 SOHC aero engine introduced by Hispano-Suiza in 1914, and was the most commonly used liquid-cooled engine in the aircraft of the Entente Powers during the First World War. The original Hispano-Suiza ...

engine. So equipped, the Navy ordered another 365 machines. In order to take full advantage of the more powerful engine, Donnet-Denhaut increased the wingspan by adding a third bay to the wing cellule and used the extra lift to incorporate a place for a second gunner, bringing the total crew to three. This version (later, the DD-8) became the most produced, with perhaps 500 aircraft built. The DD-8 was also known as the Donnet-Denhaut 300-hp. Further developments added a second machine gun to each gunner's station (the DD-9) and twin engines mounted in a push-pull configuration (the DD-10). Following the war, a few military surplus DDs were remanufactured as the Donnet HB.3 and operated commercially for a time.

Operational history

Apart from French Navy service, DD flying boats were operated by the United States Navy in Europe, flying from

Île-Tudy Île-Tudy (; ) is a commune in the Finistère department of Brittany in northwestern France. Population Inhabitants of Île-Tudy are called in French ''Îliens''. History The United States Navy established a naval air station on 14 March 1918 ...

and

Dunkirk Dunkirk (french: Dunkerque ; vls, label=French Flemish, Duunkerke; nl, Duinkerke(n) ; , ;) is a commune in the department of Nord in northern France.submarine A submarine (or sub) is a watercraft capable of independent operation underwater. It differs from a submersible, which has more limited underwater capability. The term is also sometimes used historically or colloquially to refer to remotely op ...

s. Some 50 aircraft of this type were purchased, and the first attack (against ''U-108''; unsuccessful) took place on 23 April 1918.

Operators

; * French Navy ; * Portuguese Naval Aviation ; * United States Navy

Specifications (DD-8)

Notes

References