Supermarine Stranraer gallery

The Supermarine Stranraer marked the end of biplane flying-boat development for the Royal Air Force. They entered service in 1937 and many were still 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 They were withdrawn from operational service in March 1941 but continued to serve in a training capacity until October 1942.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 J.R. 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 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) was delivered to the RAF on 24 October 1934. On 29 August 1935, an initial order was placed for 17 aircraft (K7287 to K7303) to the production specification 17/35.

General characteristics

Crew: 6-7
Length: 54 ft 9 in (16.7 m)
Wingspan: 85 ft 0 in (25.9 m)
Height: 21 ft 9 in (6.6 m)
Wing area: 1,457 ft² (135.4 m²)
Empty weight: 11,250 lb (5,100 kg)
Loaded weight: 19,000 lb (8,620 kg)
Powerplant: 2× Bristol Pegasus X radial engines, 920 hp (685 kW) each

Performance

Maximum speed: 165 mph (265 km/h) at 6,000 ft (1,830 m)
Range: 1,000 mi (1,610 km)
Service ceiling: 18,500 ft (5,640 m)
Rate of climb: 1,350 ft/min (6.8 m/s)
Wing loading: 13 lb/ft² (63.7 kg/m²)
Power/mass: 0.097 hp/lb (159 W/kg)

Armament

3 x 0.303 in (7.7 mm) Lewis guns
1,000 lb (454 kg) of bombs or depth charges