Shvetsov M-25

The Shvetsov M-25 was an aircraft radial engine produced in the Soviet Union (USSR) in the 1930s and 1940s, a licensed production variant of the Wright R-1820-F3.

Shvetsov M-25A.jpg
Type Radial engine
Manufacturer Shvetsov
Number built 13,888
Developed from Wright R-1820
Developed into Shvetsov ASh-62

Design and developmentEdit

The first M-25s were produced from kits imported from the United States; the main difference between the later M-25 and the R-1820-F3 was the use of metric components. 13,888 M-25s were produced in the USSR at factories in Perm and Kazan. There were a number of sub-variants which differed from the original M-25 in that they had reduction gears, rather than direct drive. Performance was similar to the equivalent Wright engines. The M-25 was later developed into the ASh-62 and was later used as a pattern for the M-70. The M-70, a twin-row 18-cylinder engine, eventually developed into the ASh-73 which powered the Tupolev Tu-4, a reverse-engineered copy of the Boeing B-29.


Specifications (Shvetsov M-25)Edit

Family tree of Shvetsov engines

General characteristics

  • Type: 9-cylinder, air-cooled, radial engine
  • Bore: 155.5 mm (6.122 in)
  • Stroke: 174.5 mm (6.870 in)
  • Displacement: 29.876 L (1,823.1 cu in)
  • Length: 1,100 mm (43.307 in)
  • Diameter: 1,365 mm (53.740 in)
  • Dry weight: 434 kg (957 lb)


  • Supercharger: Single speed, single stage, geared centrifugal supercharger
  • Fuel system: 1 K-25 (Solex) Carburetor


  • Power output: 520–600 kW (700–800 hp) depending on model
  • Compression ratio: 6.4:1

See alsoEdit

Related development

Related lists


  • 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.