Salmson 2

Salmson
Industry	Aircraft manufacturing, aircraft engines
Founded	1916
Headquarters	France
Products	Aircraft engines, aircraft (e.g. Salmson 2)

The Salmson 2 A.2, commonly referred to as the Salmson 2, was a French biplane reconnaissance aircraft developed by the company Salmson to meet a military specification issued in 1916. Alongside the Breguet 14, it emerged as one of the primary reconnaissance planes operated by the French army in 1918, and it was also employed by aviation units of the American Expeditionary Force. By the conclusion of World War I, Salmson 2 models represented roughly one-third of all French reconnaissance aircraft.

Design and development

During the First World War, Salmson concentrated on producing aircraft engines, particularly 9-cylinder and later 18-cylinder water-cooled radial engines inspired by the Swiss Canton-Unné design. The company's first airplane, the Salmson-Moineau S.M.1, was an unusual three-seat reconnaissance biplane featuring twin propellers powered by a single engine mounted transversely; despite limited manufacturing, it failed to achieve significant success.

The Salmson 2 was created to succeed the Sopwith 1½ Strutter and Dorand A.R. in the tactical reconnaissance (A.2) category. Although Salmson had previously produced the 1½ Strutter under license, the Salmson 2 was an original design bearing more resemblance to the Sopwith than to its earlier Salmson-Moineau predecessor. It utilized a traditional two-bay biplane structure driven by Salmson’s own Salmson 9Z water-cooled radial engine. Initial flight tests identified minor handling challenges that were promptly corrected; however, similar to the contemporary Airco DH.4, its pilot and observer were seated far apart, which hindered effective communication. Following successful trials on 29 April 1917, production was approved with deliveries commencing in October of that year. Roughly 3,200 units were manufactured in France—about 2,200 by Salmson itself, with the remainder produced by firms such as Latécoère, Hanriot, and Desfontaines. A number of these were configured as Salmson 2 E.2 dual-control advanced trainers.

Variants

Notable versions of the Salmson 2 included:

Salmson 2 A.2 – primary reconnaissance variant.
Salmson 2 E.2 – dual-control trainer for advanced instruction.
Salmson 4 Ab.2 – larger, armored model designed for ground-attack missions; produced in limited quantities in 1918 and discontinued after the war.
Salmson 5 A.2 – altered design that did not enter production.
Salmson 7 A.2 – redesigned with pilot and gunner seated back-to-back within a single cockpit; intended for mass production but cancelled postwar.
Salmson Limousine – military Salmson 2s converted into enclosed civilian passenger aircraft after WWI.
Salmson 2 Berline – civilian conversions featuring open cockpits for passenger use.
Kawasaki Army Otsu-1 (乙-1) Reconnaissance Aircraft – Japanese license-built version of the Salmson 2 A.2.

Operational history

In addition to its deployment by French forces, approximately 700 Salmson 2 aircraft were procured and effectively operated by American air units during World War I.

Following the war, Czechoslovakia acquired Salmson 2s which remained operational until 1924. Poland obtained some examples but replaced them by 1920 with Bristol F.2B aircraft. In Japan, production under license resulted in the Army Type Otsu 1, also known as Kawasaki-Salmson. Production figures are unclear; Kawasaki manufactured about 300 units while an estimated similar number were built at the Imperial Japanese Army’s Tokorozawa facility, potentially totaling near 1,000 aircraft.

Postwar, Latécoère-built Salmson 2 A.2s became the inaugural aircraft employed by French airmail pioneer Aéropostale.