Gnome Sigma

The Gnome 7Σ Sigma (commonly called the Gnome 60 hp) is a French seven-cylinder, air-cooled rotary aero engine.

[1] The Sigma produced 60 hp (45 kW) from its capacity of 9.5 L (579.73 cu in).

Data from Société Des Moteurs Gnome[2] Comparable engines Related lists

Longitudinal elevation of Gnome 7 Sigma, from 1913 Gnome catalog