Shvetsov ASh-21

The Shvetsov ASh-21 is a seven-cylinder single-row air-cooled radial aero engine.

Design and development

The ASh-21 is basically a single-row version of the Shvetsov ASh-82. The ASh-21 also incorporates a number of parts from the ASh-62 radial engine. Design began in 1945, and by 1947 testing had finished and production had begun. Between 1947 and 1955 7,636 ASh-21 engines had been built in the USSR and beginning in 1952 it was produced in Czechoslovakia as the M-21.

Applications

• Yak-11
• Yak-16
• Beriev Be-8
• Beriev Be-30 (prototype)

Specifications (Shvetsov ASh-21)

Family tree of Shvetsov engines

General characteristics

• Type: seven-cylinder, air-cooled, single-row, radial engine
• Bore: 155.5mm (6.12in)
• Stroke: 155mm (6.10in)
• Displacement: 20.6 Liters (1,257 cu in)
• Dry weight: 487kg (1,074lb)

Components

• Supercharger: Single stage, single speed, geared centrifugal supercharger
• Fuel system: Carburetor
• Cooling system: Air

Performance

• Power output:
  
• 520 kW (700 hp) at 2,300 rpm takeoff power
• 459 kW (615 hp) at 1,700 m (5,580 ft)
• Specific power: 25.5 kW/L (0.56 hp/in³)
• Compression ratio: 6.4:1
• Power-to-weight ratio: 1.07 kW/kg (0.65 hp/lb)

References

• Gunston, Bill (1986). World Encyclopedia of Aero Engines. Wellingborough: Patrick Stephens. p. 175. 
• Kotelnikov, Vladimir (2005). Russian Piston Aero Engines. Crowood Press Ltd. pp. 118–119.