TheShvetsov M-11 was designed under a 1923 competition in theSoviet Union for a new engine to powertrainer aircraft. It is a single-row five-cylinder air-cooledradialpiston engine with aluminum cylinder heads. Like the AmericanKinner B-5 5-cylinder radial of similar size, the M-11 had individualcamshafts for each cylinder, operating thepushrods, rather than a single central cam ring. The initial versions of the M-11 suffered from a shortservice life of only 50 hours. The basic M-11 engine had a power output of 100 hp (73 kW), the newer M-11D variant was higher at 125 hp (92 kW). The ultimate version, M-11FR, introduced in 1946, increased power output to 160 hp at 1,900 rpm on takeoff and 140 hp at cruise and had provisions for a variable-pitchpropeller, accessory drive (forvacuum pumps,compressors,generators, etc.) and featured a floatlesscarburetor.
An alternative designation for the M-50 three cylinder derivative of the M-11
M-12
A 190 hp (140 kW) development of the M-11 by M.A. Kossov, un-related to the NAMI-100, which had been earlier designated M-12.
M-12 (M-11Ya)
A projected development of the M-11 atGAZ-41. The prototype was run but results were unsatisfactory, re-designated from M-11Ya
M-13 (M-13K)
A 1944 development by M.A. Kossov to be assembled from various M-11 variants
M-13
In parallel with the M-13K, E.V. Urmin at GAZ-41 mated cylinders from the M-11D with new crankshaft and crankcase
M-13
A later M-13 was created by I.A. Muzhilov at OKB-41 in 1946. Despite passing state acceptance test in June 1948, this engine was not put into production.
Development of the M-51 at theNIIGVF (Nauchno-Issledovatel'skiy Institut Grazdahnskovo Vozdooshnovo Flota - civil air fleet scientific test institute) by M.A. Kossov. 110 kW (150 hp) / 130 kW (180 hp)
The M-11 powered a number of Soviet, Bulgarian and Polish aircraft. The M-11 remained in production until 1952 with an estimated total of over 100,000 engines made. Several hundreds of M-11D and M-11FR-1 variants were manufactured under license in the PolishWSK-Kalisz works inKalisz. It was also used for the up-enginedGAZ-98Kaerosani winter-used sled in apusher configuration, and as the standard powerplant for the similarNKL-26 propeller-driven sledges during the World War II years.
