Gnome Type N Rotary Engine

Type: Rotary, 9 cylinders

Power rating: 123 kw (165 hp) at 1,350 rpm

Displacement: 15.9 L (970.38 cu in.)

Bore and Stroke: 115 mm (4.53 in.) x 170 mm (6.69 in.)

Weight: 132 kg (290 lb)

The first successful rotary engine is generally attributed to the American F.O. Farwell in 1896; but the French Gnome, developed by the Seguin brothers, was much more successful in bringing the rotary to a broad aviation market beginning in 1909. The original Gnome had two valves, with the inlet in the piston head and exhaust in the in the cylinder head. The monosoupape, as the name signifies, had only one valve in the cylinder head, eliminating a weak feature of the earlier design, and was the most numerous model during World War I.

Used mainly on fighter aircraft where speed and maneuverability were especially important, rotary engines were light and compact for their power. However, excessive engine torque and gyroscopic forces made airplanes difficult to control, causing high oil and fuel consumption. The Type N was particularly reported to have excessive fuel consumption.

This engine powered the Nieuport 28C.1, Sopwith F.1 Camel, Vickers F.B.9, Bleriot, and Pomier aircraft.