During the First World War, the Salmson factory built aircraft engines, generally 9- and later 18-cylinder water-cooled radial engines developed from the
Swiss Canton-Unné design, an early stationary radial engine design used for military aircraft. The company's first aircraft was the
Salmson-Moineau S.M.1, an unusual three-seat reconnaissance biplane with twin propellers gear-driven from a single Salmson engine mounted sideways in the fuselage but it was not successful although it saw limited production. The Salmson 2 came from a requirement to replace the
Sopwith 1½ Strutter and
Dorand A.R. reconnaissance aircraft in the A.2 (tactical reconnaissance) role. Salmson had built the 1½ Strutter under license, and the Salmson 2, while an original design, had more in common with the Sopwith than to the Salmson-Moineau. The aircraft was of conventional construction with a two-bay biplane configuration, powered by the company's own
Salmson 9Z water-cooled radial engine. Some minor control problems were quickly resolved in early testing, but the main defect of the Salmson 2, shared with the contemporary
Airco DH.4, was that the pilot and gunner were widely separated, making communication difficult. Production was ordered after trials on 29 April 1917, and deliveries were underway by October of that year. Around 3,200 Salmson 2s were built in France, 2,200 by Salmson and the remainder by the
Latécoère,
Hanriot, and
Desfontaines, companies. Some of these were
Salmson 2 E.2 dual control advanced training (
Ecole) aircraft. ==Variants==