Klimov VK-107

The Klimov VK-107 was a V-12 liquid-cooled piston aircraft engine used by Soviet aircraft during World War II.

Development
The VK-107 was developed from the M-105 and VK-106. To achieve a greater power output, each cylinder now had four valves (two intake and two exhaust), crankshaft and camshafts were completely revised, and a new supercharger design was implemented. Although the engine could have been ready for production as early as 1942, the Soviets' factories lacked the capacity to produce a brand new design. Thus, the less powerful Klimov VK-105PF and VK-105PF2 V12 engines were built instead. However, the appearance of Luftwaffe Messerschmitt Bf 109G with Daimler-Benz DB 605 engine in 1943 created an urgent demand for a more powerful engine. VK-107A was put into production in 1944 and was used on Yak-9U fighters. The engine was not well liked by either pilots or mechanics – it had a life expectancy of only 25 hours and war emergency power was almost never used for fear of decreasing this even more. The engine was also difficult to service, in part because its exhaust headers were on the inside of the cylinder banks, the reverse placement of most V-type liquid-cooled engine designs.

Variants
Data from Aircraft engines of the World 1953 and Russian piston aero engines
 * M-107: (M-107P) Initial designation, produced 1941-1942; 686 built.
 * VK-107:Prototypes with take-off rating of 1450 hp
 * VK-107A: 1942 production version without water-injection with military (high) rating of 1500 hp at 2800 rpm and 14800 ft, remained in production until 1948
 * VK-107B:with water injection
 * VK-107R: version for hybrid piston-motorjet powered Mikoyan-Gurevich I-250 and Sukhoi Su-5 fighters fitted with the Kholshchevnikov VRDK
 * VK-107 coupled:A projected coupled powerplant driving contra-rotating propellers
 * VK-108:attempt to further develop VK-107 with a rating of 1850 hp for takeoff, used on several Yakovlev Yak-3 and Myasishchev DB-108 prototypes but did not enter production.
 * VK-108F:Boosted VK-108
 * VK-109: 1945-6 development of the VK-108, planned for use on the Myasishchev VB-109 bomber.

Applications

 * Mikoyan-Gurevich MiG-7
 * Petlyakov Pe-2
 * Yakovlev Yak-3
 * Yakovlev Yak-9