FAIREY GANNET (ANTI-SUBMARINE AIRCRAFT)

During the course of World War II, the Royal Navy had learned the value of carrier based anti-submarine aircraft. For the post war years the Navy needed a modern aircraft to tackle the submarine threat posed by any potential enemy.

In 1945 the Fleet Air Arm issued a requirement GR17/45, for a carrier-based ASW (anti-submarine warfare) aircraft which could both hunt and kill submarines.

Of two cosmetically similar designs built to prototype standard, it was the Fairey design that ultimately won the contract, having flown for the first time on September 19, 1949. The aircraft had a deep barrel like fuselage to accommodate both sensors and weapons for hunting and killing enemy craft. Power came from Armstrong Siddeley Double Mamba engine which was actually two turboprop engines driving a shared gearbox. This in turn drove a contra-rotating propeller system.

The Double Mamba was chosen because one of the engines could be shut down for more economical

cruising flight. Conventional twin engine aircraft exhibit problematic handling if one engine fails, resulting in what is known as asymmetric flight. In this situation the working engine forces its side of the aeroplane ahead of the other side, resulting in crabbing flight path, as well as major concerns on landing. If one Double Mamba failed this would not be an issue for the pilot of a Gannet.

The Fairey 17 began carrier-deck trials in early 1950 and on June 19 that year the aircraft made he first landing of a turboprop aircraft on a carrier HMS Illustrious. The Admiralty then requested that search radar be included, as well as a third seat for the operator, resulting in a third modified prototype which flew in May 1951. When Fairy’s aircraft won the competition to go into production, the name “Gannet” was given to the aircraft. The Gannet brimming with equipment and weapons was a technically complicated aircraft, an example being the wings that folder not once bur twice for under deck stowage. Because of development delays the Gannet AS.1 did not enter FAA service until 1955, some ten years after the requirement was first issued.

The fuselage had a big weapons bay to accommodate two torpedoes or other munitions up to a total of 2000lb. A retractable radome under the rear fuselage housed the search radar. When the extendible “dustbin” radome was added, it led to lateral instability in flight which was remedied by the addition of two auxiliary fin lets to the horizontal tail plane. Simply raising the height of the vertical tail plane would have had the same effect but would have exceeded below deck hangar height limits. The “Gannet’s” crew of three sat in tandem with pilot, observer/navigator and radio/radar operator each in their own cockpits, the radio/radar operator’s seat facing the tail of the aircraft.

A number of Gannets were operated by foreign air arms. Deliveries to the Royal Australian Navy for carrier operations began 1955 (phased out in 1967) while the former West German naval air arm operated Gannets from shore bases phasing them out in 1965. Indonesia obtained refurbished Royal Navy examples.

A total of 181 Gannet AS.1 were built together with 38 Gannet T.2 conversion trainers for training pilots on idiosyncrasies of the aircraft and its unique power plant. In 1956 the improved 3035hp Double Mamba 101was introduced into Gannets on the production line. Aircraft thus powered were designated AS.4 and T.5 for the trainer version. The Gannet AS.6 was the AS.4 with a new 1961 radar and electronics fit.

 Fairey were also contracted to produce an airborne early warning (AEW) Gannet to replace the Douglas Skyraider in Fleet Air Arm service. Designated AEW.3 these were new build dedicated early warning aircraft with a huge radar installation mounted on the underside of the fuselage beneath the cockpit. This version which served until 1977 carried a pilot and two radar plotters who were housed in a rear cabin.