The Norman Thompson N.T.4 was a twin-engined British flying boat of the First World War. Although less well known than similar Curtiss and Felixstowe flying boats, 50 were ordered for Britain's Royal Naval Air Service.
N.T.4 | |
---|---|
NT4A, February 1918. | |
Role | Patrol Flying Boat |
Manufacturer | Norman Thompson Flight Company |
Designer | Francis Percy Beadle[1] |
First flight | October 1916 |
Introduction | 1916 |
Retired | 1918 |
Primary user | Royal Naval Air Service |
Number built | 26 (N.T.4), 44 (N.T.4A), 2 (N2C) |
Variants | Gosport Mail |
Development and design
editThe White and Thompson company was formed by Norman Thompson and Douglas White in 1912 at Bognor Regis, Sussex to design and build aircraft.[2] It built several models of aircraft in small numbers, before being renamed the Norman Thompson Flight Company in September 1915.
The first aircraft to be produced by the renamed company was a twin-engined patrol flying boat, the Norman Thompson N.T.4. This was a three bay biplane powered by two pusher Hispano-Suiza engines mounted between the wings and was fitted with an enclosed, heavily glazed cockpit for its four-man crew.
An initial order for ten aircraft for the Royal Naval Air Service was placed in December 1915, with the first prototype flying in October 1916.[3] Further orders were placed in 1917 bringing the total ordered to 50. Production continued through 1917, but in 1918, following a change in policy on anti-submarine aircraft, the final contract for 20 aircraft was cancelled.[4] Total production was 26 aircraft, continuing until June 1918.[5]
Norman Thompson produced a revised design to meet the requirements of Admiralty Specification N.2C, to replace the N.T.4. This type, designated the Norman Thompson N.2C used the wings of the N.T.4 but with a new hull resembling that of the Porte/Felixstowe boats. Power was by two 200 hp (149 kW) Sunbeam Arab engines. The first prototype attempted to fly on 1 August 1918, but required changes to the hull before it was capable of take-off. Water handling remained poor, and the aircraft was tail heavy in flight. It was abandoned following the end of the war.[6]
Operational history
editThe N.T.4 entered service with the RNAS in 1916,[7] being operated on anti-submarine patrols over the North Sea and English Channel but were mainly used for training, as larger aircraft were more suitable for patrol purposes.[8] Many of the aircraft produced in 1918 were delivered straight to storage and were never used.[4] Owing to its similarity in size to the Curtiss H-4, it shared the Curtiss flying boat's nickname of America, being renamed Small America when the larger Curtiss H-12 (known as Large America) and Felixstowe F.2 flying boats came into service.[9]
Variants
edit- N.T.4
- Initial batch of six aircraft. Powered by two 150 hp Hispano-Suiza engines.
- N.T.4A
- Main production type. Powered by 200 hp geared Hispano-Suiza engines. 44 built.
- N2C
- Improved version with hull similar to Felixstowe flying boats, powered by two Sunbeam Arab engines. Two prototypes only built in 1918.[10]
Operators
editSpecifications (N.T.4A)
editData from British Naval Aircraft since 1912 [9]
General characteristics
- Crew: 4
- Length: 41 ft 6 in (12.65 m)
- Wingspan: 78 ft 7 in (23.95 m)
- Height: 14 ft 10 in (4.52 m)
- Wing area: 936 sq ft (87.0 m2)
- Empty weight: 4,572 lb (2,074 kg)
- Gross weight: 6,469 lb (2,934 kg)
- Powerplant: 2 × Hispano-Suiza 8B V-6 water-cooled piston engines, 200 hp (150 kW) each
- Propellers: 2-bladed fixed-pitch propellers
Performance
- Maximum speed: 95 mph (153 km/h, 83 kn) at 2,000 ft (610 m)
- Cruise speed: 69 mph (111 km/h, 60 kn)
- Endurance: 6 hours[11]
- Service ceiling: 11,700 ft (3,600 m)
- Time to altitude: 10,000 ft (3,048 m) 31 minutes 5 seconds
- Wing loading: 6.91 lb/sq ft (33.7 kg/m2)
- Power/mass: 0.062 hp/lb (0.102 kW/kg)
Armament
- Guns: Provision for Lewis guns firing through side window
- Bombs: Bomb racks under lower wing
See also
editRelated development
- Gosport Mail
Aircraft of comparable role, configuration, and era
Notes
edit- ^ Moss, Roger. "Francis Percy Hyde Beadle". British Aviation – Projects to Production. Retrieved 10 February 2017.
- ^ Goodall 1995, pp. 7–8.
- ^ Goodall 1995, pp.44–45.
- ^ a b Goodall 1995, p.49.
- ^ Goodall 1995, pp.49,53.
- ^ London 2003, pp.39–40.
- ^ "English Heritage Aircraft utilised by the RFC, RNAS, RAF and US Navy within the UK 1912–18" (PDF). Retrieved 17 September 2007.
- ^ Goodall 1995, p.47.
- ^ Donald 1997, p. 695
- ^ Goodall 1995, p.52.
References
edit- Donald, David, ed. (1997). The Encyclopedia of World Aircraft. Aerospace Publishing. ISBN 1-85605-375-X.
- Goodall, Michael H. (1995). The Norman Thompson File. Tunbridge Wells, UK: Air Britain. ISBN 0-85130-233-5.
- London, Peter (2003). British Flying Boats. Stroud, UK: Sutton Publishing. ISBN 0-7509-2695-3.
- Thetford, Owen (1978). British Naval Aircraft since 1912 (Fourth ed.). London: Putnam. ISBN 0-85177-861-5.
External links
edit- Norman Thompson N.T.4: British Aircraft Directory