Shvetsov M-11

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The Shvetsov M-11 was designed under the 1923 competition for a new engine to power trainer aircraft. It is a single-row five-cylinder air-cooled radial piston engine with aluminum cylinder heads. Uniquely, pushrods actuating the valves were driven by individual cams on each cylinder rather than a single central cam. First versions of M-11 suffered from a short serice life of only 50 hours. The ultimate version, M-11FR, introduced in 1946, increased output to 160 hp at 1,900 rpm on takeoff and 140 hp at cruise and had provisions for a variable-pitch propeller, accessory drive (for vacuum pumps, compressors, generators, etc.) and featured a floatless carburetor. M-11 powered a number of aircraft, including Polikarpov Po-2, Yakovlev UT-1, Yakovlev UT-2, Yakovlev Yak-6, Yakovlev Yak-12, Yakovlev Yak-18 and Polish LWD Junak. M-11 remained in production until 1952 with an estimated total of over 100,000 engines made.

[edit] Specifications (M-11)

General characteristics

• Type: 5-cylinder air-cooled radial engine
• Bore:
• Stroke:
• Displacement: 8.6 L (525 in³)
• Dry weight: 165 kg (363 lb)

Components

• Cooling system: Air-cooled

Performance

• Power output:
  
  • 82 kW (110 hp) at 1,650 rpm for takeoff
  • 75 kW (100 hp) cruise
• Specific power: 9.5 kW/L (0.21 hp/in³)
• Compression ratio: 5.0:1
• Power-to-weight ratio: 0.50 kW/kg (0.30 hp/lb)