Shvetsov ASh-21

ASh-21
Type	Radial engine
Manufacturer	Shvetsov OKB-19 in Perm'
First run	1945
Number built	7,636
Developed from	Shvetsov ASh-82

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

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.

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