Blériot-SPAD S.81

The Blériot-SPAD S.81, designated S.81 C.1 in service, was a French fighter aircraft developed in 1923 to a requirement by the French Air Force. It was flown competitively against the Dewoitine D.1 and was selected over it because of the Dewoitine's more radical design, leading to an order for 80 aircraft. The S.81 was a single-bay biplane of conventional configuration with I-shaped interplane struts and without Herbemont's usual swept upper wing, with a wooden monocoque fuselage and metal wings skinned in fabric. Production versions had a lengthened fuselage and a larger tail fin. A single S.81bis racer was built for the Coupe Michelin, with poor performance, and the production S.81/1 had a 220 kW Hispano-Suiza 8Fb V-8 engine.