The Supermarine Scapa was a British general reconnaissance flying boat built by Supermarine that was used by the Royal Air Force between 1935 and 1939.
It was developed from the Southampton and formed the basis of the later Stranraer flying boat.
After experimenting with a three engine design of flying boat, (the Nanok/Solent/Southampton X), Supermarine’s chief designer, R.J. Mitchell, decided that the good hydrodynamic design that had been developed in the twin engined Southampton, would be the platform for the next aircraft.
A prototype designated the Southampton IV was built.
It had a hull that performed even better in the tank tests.
An Air Ministry Specification was received in November 1931.
The test pilot Joseph “Mutt” Summers took the first flight on 8 July 1932.
The name had then been changed to the Scapa.
15 Scapa’s were built before production was changed to a more powerful development, the Stranraer.
The Scapa hull was an all metal structure, while the wing and tail surfaces had metal structure with fabric covering.
The two Rolls-Royce Kestrel V-12 engines were mounted in nacelles underslung from the upper wing, and there were two fins, each placed at the mid semi-span of the tailplane.
Similar to the Southampton, there were three gun positions provided, one in the nose and two staggered in the rear fuselage.
They were provided each one with a single .303 British (7.7 mm) calibre Lewis Mk.I machine guns.
53 ft 0 in (16.15 m) on beaching gear
75 ft 0 in (22.86 m)
21 ft 0 in (6.40 m) on beaching gear
1,300 sq ft (120 m2)
10,030 lb (4,550 kg)
16,080 lb (7,294 kg)
2 × Rolls-Royce Kestrel IIIMS,
V-12 liquid cooled piston engines,
525 hp (391 kW) each
2 bladed wooden fixed pitch propellers
142 mph (229 km/h, 123 kn) at 3,280 ft (1,000 m)
100 mph (160 km/h, 87 kn) at 5,000 ft (1,524 m)
64 mph (56 kn; 103 km/h)
1,000 mi (1,600 km, 870 nmi) with 2,650 lb (1,202 kg) military load