Le Rhone 9C 80HP Rotary Aero Engine

French designed rotary 9-cylinder, single-row air-cooled poppet-valve engine of US Manufacture. Also manufactured in France, England, Italy. Engine complete with rocker arms, valves, fixed propeller shaft, mounting plate, 3 spark plugs, induction pipe mounting gaskets but no induction pipes. Inscriptions on plate 9.24.18 US Army, Factory No. G606. 80 horsepower at 1200 rpm. 11 litre capacity. Diameter 940mm. This model is distinguished from later Le Rhone 9J variants in that the copper induction pipes in this model would have been mounted on the front of the crankcase.

The French Le Rhone rotary engine appeared in 1912, designed by Ingenieur Verdet, who had worked for Peugeot. Great numbers of Le Rhone engines were built by the Societe des Moteurs Gnome et Rhone, based in Paris. Large numbers were also built in Britain during WWI, under an associated company, The Gnome and Le Rhone Engine Company in London, in a variety of models. They were basically two-valve engines, all of similar design but differing in mechanical detail and incorporating a single push-pull valve rod and rocker. The Gnome engine used a master big-end, with slave rod attached, whereas the Le Rhone had an unusual arrangement whereby the heels or slippers of the connecting rods in the nine-cylinder engines were assembled on a thrust block in three concentric grooves, giving them limited sliding or oscillating movements as the engine rotated. The engines had steel cylinders with cast-iron liners and pistons of steel (later aluminium). They were equipped with single magnetos and Bloctube carburettors.

Engine disassembled and conserved at Metals Lab 1988/89.

Engine type fitted to Nieuport 10, 11, 21 and 82,
Ruchonnet, Hanriot, Blériot 53, Blériot-SPAD C2, Caudron G3 and G4, Morane-Saulnier LA,N and P, Sopwith F1 Camel,
Dove and Pup, H Farman type 20, Thomas-Morse S4C, Standard E1, Bristol Scout D, RAF SE4, Vickers FB12.