The Supermarine Stranraer is a flying boat designed and built by the British Supermarine Aviation Works company at Woolston, Southampton. It was developed during the 1930s on behalf of its principal operator, the Royal Air Force (RAF). It was the RAF's last and fastest biplane flying boat. Derived from the Supermarine Scapa, the aircraft's design was heavily shaped by Specification R.24/31, issued in 1931. After an initial rejection by the Air Ministry, Supermarine persisted with development as a private venture under the designation Southampton V. During 1933, a contract was placed for a single prototype; it was around this time that the type was named after Stranraer. First flown on 24 July 1934, the Stranraer entered frontline service with the RAF during 1937; most examples of the type were in service by the outbreak of World War II. The Stranraers typically undertook anti-submarine and convoy escort patrols during the early years of the conflict. During March 1941, the model was withdrawn from frontline service, but continued to be operated in a training capacity until October 1942. In addition to the British-built aeroplanes, the Canadian Vickers company in Montreal, Quebec, also manufactured 40 Stranraers under licence for the Royal Canadian Air Force (RCAF). These Canadian Stranraers served in anti-submarine and coastal defence capacities on both Canada's Atlantic and Pacific coasts, and were in regular service until 1946. Following their withdrawal from military service, many ex-RCAF Stranraers were sold off to fledgling regional airlines, with whom they served in various commercial passenger and freighter operations into the 1950s. The Stranraer was a six-seater, twin-engined biplane flying boat. Its empty weight was 11,250 pounds (5,100 kg), with a maximum take-off weight of 19,000 pounds (8,600 kg). As the design of the Stranraer progressed, it was changed from that of the Scapa, having a two-bay structure. The Stranraer's weight, and the surface area and span of its wings, were 12 per cent greater; the elevator was also 7 per cent larger, while the rudders featured trim tabs capable of holding the aircraft straight under single-engine flight. The Rolls-Royce Kestrel was initially considered as a powerplant, but eventually the moderately supercharged Bristol Pegasus IIIM radial engine was selected, . Much of the airframe was alclad, while detailed fittings were made of stainless steel; metal components were anodised as an anti-corrosion measure. For additional strength, a second pair of interplane struts were added. The hull was considerably larger, its cross-section being increased by 18 per cent, yet it had identical hydrodynamic performance. The forward gun was redesigned to be retractable, the middle gunner's position was lowered, and a tail gunner position was added just aft of the control surfaces, completed with a hooded windshield. In general, the equipment of which the aircraft was to be fitted with were the result of lessons learnt from operations of the earlier Southamptons. For more details including operational history, click here. A total of 57 aircraft were built.
