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The first versions of this engine were built in 1908, and set an 8-hour endurance record in 1910. It continued to be used through World War I, especially in British training planes. A unique feature of the engine was that the propeller was driven at one-half engine speed by being driven off of the camshaft rather than the crankshaft in the conventional manner. For cooling on tractor planes, a cowl was fitted to the engine to funnel the prop wash through the cylinders. On pusher planes, a fan was mounted opposite the propeller end to force air through a casing which partially surrounded the cylinders. Cooling the cylinders was augmented with fuel cooling. The engine powered French aircraft including Farman, Voisin, and BE 2, and British aircraft including Airco D.H.6, Alliance P.1, Avro 548, Caudron G. III, Maurice Farman Serie VII Longhorn and Serie 11 Shorthorn, Royal Aircraft Factory S.E.5a, and Vickers F.B.7A.