|Klimov M-103 engine recovered from Tupolev SB wreck|
|Type||V12 inline engine|
|First run||October 1936|
|Developed from||Klimov M-100|
|Developed into||Klimov M-105|
Design and development
The M-103 was a further development of the Klimov M-100 engine that was itself a licensed copy of the French Hispano-Suiza 12Ybrs. It differed from both engines in a number of aspects such as increased compression ratio, increased supercharger ratio, increased rpm's, strengthened cylinder blocks, a new crankshaft, a more aggressive camshaft, and flat bottomed cylinders. Developed in 1936 it was ready for testing in October 1936. The first two models failed testing due to cracked cylinder blocks and the engine was resubmitted for testing in 1937. After passing its trials it was cleared for production in 1938 and 11,681 were produced until 1942 at its factory in Rybinsk. The M-103 was followed by the M-105.
- M-103A - 148mm rather than 150mm bore cylinders.
- M-103P - A ShVAK cannon fitted to fire through the engine vee.
- M-103SP - A proposed version with two engines married to a common crankshaft.
- M-103G - With Glycol rather than water cooling.
- M-103A-TK - With an experimental Turbo-Supercharger
- M-103U - Improved service life variant.
- M-104 - Basically a M-103A with a two speed single stage supercharger for increased performance. 232 built.
- Bolkhovitinov S
- Beriev MBR-7
- Polikarpov TsKB-44
- Polikarpov VIT-1 & VIT-2
- Tupolev SB
- Yakovlev Yak-2
- Yakovlev Yak-12
- Yakovlev Yak-22
Data from 
- Type: Twelve-cylinder supercharged liquid-cooled 60° V12 engine
- Bore: 148mm (5.826 in)
- Stroke: 170mm (6.693 in)
- Displacement: 35.101 Liters (2,142.2 cu in)
- Length: 1,971 mm (77.6 in)
- Width: 764 mm (30.08 in)
- Height: 942 mm (37.08 in)
- Dry weight: 500 kg (1,101 lb)
- Valvetrain: One intake and one sodium-filled exhaust valve per cylinder actuated via a single overhead camshaft per bank.
- Supercharger: Gear-driven single-speed centrifugal type compressor. Gear ratio: 11.0:1. Maximum boost for take-off: 1,100 mm Hg (43.30 MP). Maximum boost at altitude: 920 mm Hg (36.22 MP). Critical altitude: 4,000 m (13,123 ft)
- Fuel system: Six K-100A Carburettors (License copy of Solex-Hispano 56S2 self-adjusted carburettor)
- Fuel type: 90 (minimum grade), 95 or 100 octane.
- Cooling system: Liquid-cooled
- Reduction gear: 2:3
- Power output:
- 1,000 hp (745 kW) at 2,450 RPM for take-off, boost rated at 1.44 Atm (43.30 MP)
- 960 hp (715 kW) at 2,400 RPM at 13,123 ft (4,000 m), boost rated at 1.21 Atm (36.22 MP)
- 500 hp (372 kW) at 2,450 RPM at 30,839 ft (9,400 m)
- Specific power: 21.22 kW/L (0.466 hp/in³)
- Compression ratio: 6.6:1
- Specific fuel consumption: 328 g/(kW•h) (0.54 lb/(hp•h))
- Oil consumption: 11 g/(kW•h) (0.28 oz/(hp•h))
- Power-to-weight ratio: 1.50 kW/kg (0.916 hp/lb)
- Gunston 1989, p.90.
- Valtion Lentokonetehdas (1943). Hispano-Suiza 12Y-31, M-103, M-105. Rakenneselostus, Käyttö – Ja Huoltoohjeet ["Valtion Lentokonetehdas" State Aircraft Factory: Hispano-Suiza 12Y-31, M-103, M-105. Use and Maintenance Instructions.] Helsinki: Maintenance and spare technical manual of the Finnish Government. The National Library of Finland.
- During the war, the Soviet Air Force used automotive gasoline and all kind of mixtures without troubles.