Wright R-4090
The R-4090 Cyclone 22 was an aircraft engine that was experimentally built by the American manufacturer Curtiss-Wright towards the end of World War II . It was an air-cooled multiple radial engine with supercharging. As a double radial engine , it had 22 cylinders in two levels with 11 cylinders each. With its displacement of 4090 cc , around 67,050 cm 3 , the engine developed around 2200 kW (around 3000 hp). It was only built in three copies, the last of which had coaxial propeller shafts that drove two propellers rotating in opposite directions. So the great achievement could be implemented better.
The constantly growing need for ever more powerful engines during the war forced engine designers to build engines with more cylinders. So the decision was made to test a 22-cylinder version based on the positive experience with the R-3350 . Both engines had the same stroke and bore. However, the development of the project was very difficult due to cooling difficulties and other problems. In addition, only a small development capacity was free, which is why the R-4090 was soon abandoned in favor of the further development of the R-3350 .
The R-4090 was a competitor to the Pratt & Whitney R-4360 , because both engines had similar performance characteristics. At the beginning of their development, both engines provided around 3000 hp.
22-cylinder double radial engines are extremely rare in the history of engines. There were only two other examples: the Mitsubishi Ha-50 and the Hitachi Ha-51 - both Japanese four-stroke engines, which, like the R-4090 , were developed at the end of World War II.
Technical specifications
- Type: air-cooled 22-cylinder double radial engine with supercharging
- Bore: 155.58 mm (6.125 in )
- Stroke: 160.34 mm (6.3125 in)
- Displacement: 67.05 dm 3 (4091.9 cin )
- Output: 2200 kW (3000 hp) at 2800 rpm
- maximum speed: 2800 / min
- Compression: 6.85: 1