title: Gnome Sigma
text: # Gnome Sigma
  
  The Gnome 7Σ Sigma (commonly called the Gnome 60 hp) is a French seven-cylinder, air-cooled rotary aero engine.
  
  The Sigma produced 60 hp (45 kW) from its capacity of 9.5 L (579.73 cu in).
  
  ## Specifications (7 Sigma)
  
  Data from Société Des Moteurs Gnome
  
  ### General characteristics
  
  * Type: 7-cylinder, single-row, rotary engine
  * Bore: 120 mm (4.72 in)
  * Stroke: 120 mm (4.72 in)
  * Displacement: 9.5 L (579.73 cu in)
  * Length: 1,125 mm (44.29 in)79 cm (31 in)
  * Diameter: 826 mm (32.52 in)
  * Dry weight: 79 kg (174 lb)
  
  ### Components
  
  * Valvetrain: pushrod operated overhead exhaust valves plus pressure-driven inlet valves located in the piston crowns
  * Fuel system: a single static Bloctube carburretor feeding the crankcase
  * Fuel type: 40 / 50 octane gasoline
  * Oil system: pressure-fed total loss, castor oil
  * Cooling system: Air-cooled
  * Reduction gear: Direct drive, right-hand tractor, left-hand pusher
  
  ### Performance
  
  * Power output: 45 kW (60 hp) at 1,200 rpm
  