Rotary engines were an early type of internal combustion engines, designed with an odd number of cylinders in a radial configuration.
These World War I rotary engines had a unique operating characteristic. The engine crankcase and cylinders would rotate as one unit, while the crankshaft remained stationary.
Its main application was in aviation.
Various engine types were fitted in the Sopwith Camel, most common being the Clerget 9B/9Bf and later the Bentley BR1/BR2,
but also the Gnome B2 Mono and the Le Rhóne 9 series engines were used.
Although the often-repeated tales about the gyroscopic effects of rotating engines are sometimes exaggerated, it does impact the flying characteristics of the airplane. The induced torque effect into the airframe created
a limitation for the rotary engines as aircraft grew in size requiring higher RPM and ever greater horsepower.
The Sopwith Camel was a British First World War single-seat biplane fighter introduced on the Western Front in 1917. Manufactured by Sopwith Aviation Company, it had a
short-coupled fuselage, heavy, powerful rotary engine, and concentrated fire from twin synchronized machine guns.
Though difficult to handle, to an experienced pilot it provided unmatched maneuverability.
A superlative fighter, the Camel was credited with shooting down 1,294 enemy aircraft, more than any other Allied fighter of the war. It also served as a ground-attack
aircraft, especially near the end of the conflict, when it was outclassed in the air-to-air role by newer fighters.
Approximately 5,490 units were ultimately produced.