Supermarine Stranraer The Supermarine Stranraer was a 1930s British flying boat designed and built by Supermarine Aviation Works principally for the Royal Air Force . They entered operations in 1937 and many were in service at the outbreak of the Second World War undertaking anti - submarine and convoy escort patrols . They were withdrawn from operational service in March 1941 but continued to serve in a training capacity until October 1942 . Design and development . Designed by R . J . Mitchell as a tender to Air Ministry R . 24 / 31 Specification for a coastal reconnaissance flying boat for the RAF , it was initially turned down but Supermarine proceeded with the type as a private venture first known as the Southampton V . A contract was placed in 1933 for a prototype powered by two 820 hp ( 611 kW ) Bristol Pegasus IIIM and the type became known as the Stranraer . The structure was mainly duralumin , with the hull covered with sheet metal and the wings with fabric . Following the initial flight - test programme , the Stranraer prototype ( " K3973 " ) on 24 October 1934 was delivered to the RAF . On 29 August 1935 , an initial order was placed for 17 aircraft ( serial numbers " K7287 " to " K7303 " ) to the Air Ministry Specification 17 / 35 . The production version was fitted with the 920 hp ( 686 kW ) Pegasus X and first flew in December 1936 , entering service operations on 16 April 1937 ; the last Stranraer was delivered 3 April 1939 . An additional order for six aircraft ( " K9676 " to " K9681 " ) was placed in May 1936 , but subsequently cancelled . A total of 40 Stranraers were built in Canada by Canadian Vickers Limited ; Supermarine and Canadian Vickers being subsidiaries of Vickers - Armstrongs . Operational history . In service , only 17 Stranraers were operated by the RAF 1937 - 1941 primarily by No . 228 , No , 209 , No . 240 Squadrons along with limited numbers at the No . 4 OTU . Generally , the aircraft was not well - received as its performance was considered marginal . Due to its less than favourable reception by flight and ground crews , the Stranraer gained a large number of derisive nicknames . It was sometimes referred to as a " " whistling shithouse " " because the toilet opened out directly to the air and when the seat was lifted , the airflow caused the toilet to whistle . The Stranraer also acquired " Flying Meccano Set , " " The Marpole Bridge , " " Seymour Seine Net , " " Strainer , " " Flying Centre Section of the Lion ' s Gate Bridge " as well as a more genteel variant of its usual nickname , " Whistling Birdcage . " Royal Canadian Air Force Stranraers were exact equivalents of their RAF counterparts and while they were employed in coastal patrol against submarine threats in a similar role to the British Stranraers , no enemy action was recorded . The Canadian Vickers - built Stranraers served with the RCAF until 1946 . 13 examples were sold through Crown Assets ( Canadian government ) and passed into civilian use after the war , several serving with Queen Charlotte Airlines ( QCA ) in British Columbia and operated until 1957 . A re - engine project by the airline substituted Wright GR - 1820 - G202GA engines in place of the original Pegasus units . In QCA use , the Stranraer gained a more suitable reputation and was " well liked " by its crews . A total of eight surplus Stranraers were also sold to Aero Transport Ltd . of Tampa , Florida . Surviving aircraft . A single intact Stranraer , 920 / CF - BXO , survives in the collection of the Royal Air Force Museum London . This aircraft was built in 1940 , one of 40 built by Canadian Vickers . In service with the Royal Canadian Air Force , it flew with several squadrons , on anti - submarine patrols , as a training aircraft and carrying passengers . In 1944 , it was disposed of . In civil service , it was flown by Canadian Pacific Airlines until 1947 , then Queen Charlotte Airlines , who replaced its original British engines with American Wright 1820s . Queen Charlotte Airlines flew it on passenger flights until 1952 , flying from Vancouver along the Pacific coast of British Columbia . It flew with several other private owners until damaged by a ship in 1966 . In 1970 , it was bought by the RAF Museum and transported to the UK . The parts of a second Stranraer , 915 / CF - BYJ are owned by the Shearwater Aviation Museum , Halifax , Canada . This aircraft also operated with Queen Charlotte Airlines until it crashed on Christmas Eve 1949 at Belize Inlet , British Columbia . Most of the aircraft was recovered in the 1980s , with the exception of the forward fuselage and cockpit .