Le Rhone Model JB, 9 Cylinder, Rotary Engine

Type: Rotary, 9 cylinders, air-cooled

Power rating: 89 kw (120 hp) at 1,300 rpm

Displacement: 15.1 L (920 cu in.)

Bore and Stroke: 112 mm (4.41 in.) x 170 mm (6.69 in.)

Weight: 147 kg (323 lb)

Societe des Moteurs Le Rhone of Paris began manufacturing air cooled rotary engines in 1910. Its rotary was sufficiently different than that first developed by the highly successful Seguin brothers of the Societe des Moteurs Gnome, also of Paris, that it circumvented relevant Gnome patents; but was taken over by Gnome in 1914. Because Le Rhone products were in some ways superior to Gnome, its design engineers were permitted to continue development during World War I, resulting in large scale production of various nine cylinder engines.

The Model J is most famous for its connection to the Nieuport 17, the French fighter flown by aces Rene Fonck, William Bishop, Charles Nungesser, Albert Ball, and Georges Guynemer. The engine's success prompted the Germans to try to salvage and duplicate Le Rhones from downed French and British fighters. Many salvaged Le Rhones and their German-built copies saw service in such fighters as the Fokker Dr.1 Triplane.