title: Wright R-1300 Cyclone 7
text: # Wright R-1300 Cyclone 7
  
  The Wright R-1300 Cyclone 7 is an American air-cooled seven-cylinder supercharged radial aircraft engine produced by Curtiss-Wright.
  
  ## Design and development
  
  The R-1300 is basically a single row Wright R-2600. The engine was mass-produced but not widely used. Engineering began in 1942 but the first flight of an R-1300 did not take place until 1949. The engine was produced under license by Kaiser-Frazer and later by AVCO Lycoming.
  
  The engine was used in combat — the R-1300-1A and -1B in the A model North American T-28 Trojan and the R-1300-3, -3A, -3C and -3D in the Sikorsky H-19 Chickasaw. The R-1300-1B was used to power the Ayres Thrush. The R-1300-4 and -4A were used in the N class blimp; 50 of these variants were produced by AVCO.
  
  Early-production engines had vibration problems, an improved lateral dampener in the crank brought about most of the model changes.
  
  ## Variants
  
  ### R-1300-2
  
      A direct drive version of the R-1300-1. It had a 0.5625:1 reduction drive. Both used the PD9F1 carburetor.
  
  ### R-1300-3
  
      Derated to 690.3 hp (515 kW), uses forced-air cooling fan and uses a PD9G1 carburetor.
  
  ### R-1300-4
  
      Similar to the R-1300-1, uses some different accessory components.
  
  ### R-1300-CB7A1
  
      With reduction gear for use on fixed wing aircraft.
  
  ## Applications
  
  * Hispano HA-100
  * N class blimp
  * North American T-28 Trojan
  * Rockwell Thrush Commander
  * Sikorsky H-19
  * Westland Whirlwind
  
  ## Specifications (R-1300-1A)
  
  Data from Type Certificate Data Sheet 5E-14.
  
  ### General characteristics
  
  * Type: 7-cylinder supercharged air-cooled single row radial engine
  * Bore: 6.125 in (155.6 mm)
  * Stroke: 6.312 in (160.3 mm)
  * Displacement: 1,301 cu in (21.32 L)
  * Length: 48.22 in (1,225 mm)
  * Diameter: 55 in (1,397 mm)
  * Dry weight: 1,055 lb (478 kg)
  
  ### Components
  
  * Valvetrain: Two pushrod-actuated valves per cylinder with sodium-cooled exhaust valve
  * Supercharger: 1-stage
  * Fuel system: Bendix-Stromberg PD9F1 downdraft carburetor with automatic mixture control
  * Cooling system: Air-cooled
  
  ### Performance
  
  * Power output: 800 hp (596 kW)
  * Specific power: 0.61 hp/in³ (27.94 kW/L)
  * Compression ratio: 6.20:1
  * Power-to-weight ratio: 0.76hp/lb (1.25 kW/kg)
  