On 14 May 1918, Sopwith was awarded a contract for three prototypes of a new single-seat fighting triplane, conforming to the RAF Type I specification and named the Snark. Powered by a 320hp A.B.C. Dragonfly I nine cylinder radial and featuring a plywood monocoque fuselage, the Snark was an equi-span staggered triplane and its designed armament was two synchronised 7.7mm guns on the fuselage and four weapons of similar calibre mounted two per side under the bottom wing. The first Snark was passed for flight test in September 1918, but unavailability of a Dragonfly engine and the decision to make various minor modifications delayed manufacturer's trials until September of the following year, the aircraft arriving at Martlesham Heath for official trials on 12 November 1919. The second prototype reached Martlesham on 17 March 1920, and the third prototype, with a 360hp Dragonfly la engine, late in the year. Apart from engine problems, the Snark triplanes suffered fuselage deterioration and all three were written off in 1921.
Engine: 320hp A.B.C. Dragonfly I
Max take-off weight: 1036 kg / 2284 lb
Wingspan: 8.08 m / 27 ft 6 in
Length: 6.25 m / 21 ft 6 in
Height: 3.30 m / 11 ft 10 in
Wing area: 29.91 sq.m / 321.95 sq ft
Max. speed: 209 km/h / 130 mph