Sterling (Sunbeam) Cossack, V-12 Engine

Type: Reciprocating, V-type, 12 cylinders, water cooled

Power rating: 261 kW (350 hp) at 2,000 rpm

Displacement: 18.2 L (1,113.24 cu in.)

Bore and Stroke: 110 mm (4.33 in.) x 160 mm (6.3 in.)

Weight: 471.7 kg (1,040 lb)

The Sunbeam Motor Car Co., Ltd of Wolverhampton, England began producing successful automobiles in 1910. Applying the expertise of French Chief Engineer Louis Coatalen, its first aircraft engines were designed in 1913. A total of 350 Cossack engines were produced between August 1914 and December 1918. These engines powered the: Handley Page H.P.11 O/100 Type O; Short 310-A4 and Short 310-B North Sea Scout; R36 (Beardmore) Admiralty dirigible airship and R38 (Royal Airship Works) Admiralty dirigible airship. Sunbeam’s engines were the favored supplier to the Royal Navy Air Service until late in World War I. After Coatalen’s return to France in 1923, Sunbeam effectively left the aircraft engine business.

This Cossack engine was built by the Sterling Engine Company of Buffalo, New York, a leading American manufacturer of marine engines, which undertook to build Sunbeam aircraft engines during 1917. However, only a few of the twelve-cylinder units were constructed before the work was finally abandoned.