Rare water cooled Radial Engine.
The origins of the Salmson-(Canton-Unne) 9 series date from 1909, when Georges Canton and Pierre Unné, who had patented an engine design, offered it to the Salmson company. This initial effort was ultimately abandoned due to its short running life.
A new design, a 7 cylinder water-cooled radial design was then developed by Canton and Unné. This was expanded to produce a 9 cylinder model, and also two-row 14 and 18 cylinder engines. By 1912 the 9 cylinder Salmson-(Canton-Unne), the model A9, was producing around 120 brake horsepower. While competitive with rival designs from French companies, Salmson, Canton and Unné decided to develop more powerful engines as their rivals were concentrating on engines of lower power.
The engines were produced at Salmson's factory at Billancourt. The Billancourt works were expanded during the First World War and a second factory was opened at Villeurbanne. The Salmson-(Canton-Unne) 9 series were also built by licensees in Russia, where 300 engines were built during the war, and in the United Kingdom, where around 150 engines were produced. The early water-cooled radial engines were also built under license in Britain by Dudbridge Iron Works Limited of Stroud in Gloucestershire between 1914 and 1918. All Salmson engines produced after 1920 were air-cooled.
Photo: US Air Force Museum