AD Flying Boat

Pemberton-Billing Ltd (later Supermarine Aviation Works)

Industry	Aerospace, Aircraft manufacturing
Founded	1915
Founder	Linton Hope (designer)
Products	AD Flying Boat, Supermarine Channel

The AD Flying Boat was developed by the British Admiralty's Air Department to function as a patrol aircraft capable of operating alongside Royal Navy vessels. Created during the First World War, its production ceased as the conflict drew to a close, resulting in limited operational deployment. After the war, Supermarine Aviation acquired several units and converted them into civilian transport aircraft, which became known as the Supermarine Channel.

Design and development

Conceived in 1915 by yacht designer Linton Hope, the aircraft featured a traditional biplane flying boat design. Its tail assembly was also biplane in form, equipped with dual fins and rudders. The pilot and observer were seated in tandem at the front, while the engine with a pusher propeller was positioned behind them between the wings. To enable storage aboard ships, the wings were designed to fold forward.

In 1916, Pemberton-Billing Ltd (later known as Supermarine Aviation Works) built two prototypes. The initial prototype was planned to use a 150 hp (112 kW) Sunbeam Nubian engine; however, due to its unavailability, a 200 hp Hispano-Suiza 8 engine was installed instead. Early trials revealed poor performance both on water and in flight, with significant fore and aft vibrations during take-off and excessive yaw encountered in flight. These issues were addressed through modifications to the hull, fin, and rudder designs, enabling the aircraft to enter production. Although 80 units were ordered, only 27 were manufactured. Some variants were tested with Sunbeam Arab and Wolseley Python powerplants.

Supermarine Channel

File:Supermarine Channel Det Norske Luftfartsrederi.jpg

A Supermarine Channel operated by the Norwegian airline Det Norske Luftfartsrederi in 1920.

After the Armistice of 11 November 1918, Supermarine acquired 19 AD Flying Boats for conversion into civilian aircraft under the name Supermarine Channel. The Channel I model was equipped with a 160 hp Beardmore 160 hp engine, while the Channel II featured a 240 hp Armstrong Siddeley Puma engine. These modified flying boats accommodated a pilot plus three passengers across three open cockpits.

Military Users

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• Chilean Air Force operated one unit.
• Chilean Navy procured a single Channel featuring a modified hull akin to the Supermarine Seal II in 1922.

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• Imperial Japanese Navy acquired three Channel aircraft.

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• Royal Norwegian Navy Air Service obtained four Channels powered by Beardmore engines in 1920, along with an additional former civilian model. One aircraft remained active until 1928.

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• Royal Swedish Navy purchased one Channel in 1921; it was lost during testing.

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• Royal Navy
  • Royal Naval Air Service utilized the AD Flying Boat.

Civilian Users

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• Det Norske Luftfartsrederi operated the Channel Mk I.

See also

• Sempill Mission

Sources

• Andrews, Charles Ferdinand and Morgan, Eric B., Supermarine Aircraft since 1914, Putnam, London, 1981.
• Bruce, J. M., British Aeroplanes 1914–18, Putnam, London, 1957.
• London, Peter, British Flying Boats, Sutton Publishing, Stroud, UK, 2003.
• Nerdrum, Johan, Fugl Fønix: En beretning om Det Norske Luftfartselskap, Gyldendal Norsk Forlag, Oslo, 1986.