Tumansky M-88

The M-88 was designed to address the shortcomings of the Tumansky M-87. The improvements incorporated in the M-88 were a strengthened crankcase, crankshaft, connecting rods, waffle ribbing at the piston bottom and a two speed geared centrifugal supercharger. The M-88 retained the same bore/stroke and displacement as the M-87 while increasing power to 1,000-1,150 hp. Design work began in 1937 and by 1939 the first prototypes were being flight tested in the Polikarpov I-180 fighter prototypes.[1] At first the M-88 was not a success, but the designers persisted and the M-88 was made into a reliable and widely produced engine. There were a number of different variants with the most numerous being the M-88B, of which 10,585 were produced at Zaporozhye and Omsk. The M-88B solved most of the mechanical failures associated with the M-87 and early M-88's by including oil injectors in the crankshaft, improved cooling and strengthened drive components. 16,087 M-88's were produced. In hindsight, the Tumansky family of engines developed from the Gnome-Rhône 9K and Gnome-Rhône 14K were far less successful than the Shvetsov family of engines developed from the Wright R-1820.[1]

• Ilyushin Il-4
• Neman R-10
• Polikarpov I-180
• Sukhoi Su-2

Family tree of Tumansky engines

General characteristics

• Type: 14-cylinder twin-row air-cooled radial engine
• Bore: 146 mm (5.75 in)
• Stroke: 165 mm (6.50 in)
• Displacement: 38.72 L (2,363 cu in)
• Dry weight: 684 kg (1,508 lb)

Components

• Supercharger: Two-speed, geared centrifugal
• Cooling system: air-cooled

Performance

• Power output: 1,100hp
• Compression ratio: 6.1:1