Klimov M-105

From Wikipedia, the free encyclopedia

Klimov M-105 is a V-12 liquid-cooled piston aircraft engine used by Soviet aircraft during World War II.

1 Development
2 Variants
3 Specifications (VK-105PF)
4 Related content

[edit] Development

M-105 was designed in 1940, undoubtedly drawing on Klimov's experience with Hispano-Suiza 12Y (license-built as Klimov M-100). In addition to a two-speed supercharger, M-105 had several innovations like two exhaust valves per cylinder and counterbalanced crankshaft. About 91,000 M-105 and its variants were built.

During the war, Klimov's engines were redesignated from "M" (for "motor," engine) to "VK" for the lead designer's initials.

[edit] Variants

M-105P - able to accept an autocannon in the "vee" between cylinder blocks. Installed on the majority Soviet pre-war fighters - Yak-1, LaGG-1 and several experimental aircraft.
M-105PA - improved 1941 version.
M-105PF (VK-105PF) - 1942 modification with significantly increased power output at the expense of decreased high-altitude performance. In spite of Klimov's concerns about decreased service life, the engine was pressed into production at the insistence of Yakovlev. As further exploitation of "PF" version showed this was a right decision. "PF" was installed on the most numerous versions of "Yak" fighters - Yak-1B, Yak-7B, Yak-9.
VK-105PF2 - further increase in power output, it was believed that this version had exhausted the potential of the M-105 design for greater performance. "PF2" was installed in the Yak-3.
M-105PD - experimental high-altitude version, unsuccessful.
M-105R - decreased reduction ratio for bomber aircraft. Installed on Pe-2, BB-22 (Yak-4) and others.
M-105RA - same as M-105PA with decreased reduction ratio for bomber aircraft.

[edit] Specifications (VK-105PF)

General characteristics

Type: 12-cylinder supercharged liquid-cooled Vee piston aircraft engine
Bore:
Stroke:
Displacement: 35.0 liters (2,135 in³)
Dry weight: 620 kg (1,365 lb)

Components

Valvetrain: Two exhaust valves per cylinder
Supercharger: Gear-driven single-stage two-speed centrifugal type supercharger
Fuel type: 95-octane rating gasoline
Cooling system: Liquid-cooled

Performance

Power output:
- 903 kW (1,210 hp) at 2,600 rpm for takeoff
- 880 kW (1,180 hp) at 2,700 m (8,860 ft) cruise
Specific power: 25.8 kW/L (0.57 hp/in³)
Compression ratio: 7.1:1
Power-to-weight ratio: 1.46 kW/kg (0.89 hp/lb)