| R-4090 Cyclone 22 | |
|---|---|
| Type | 22-cylinder air-cooled two-rowradial piston engine |
| National origin | United States |
| Manufacturer | Wright Aeronautical |
| Number built | c. 3 |
| Developed from | Wright R-3350 Duplex-Cyclone |
TheWright R-4090 Cyclone 22 was an American experimentalradial piston engine designed and built in prototype form byWright Aeronautical during the 1940s.
During the 1940s,Wright Aeronautical Corporation was constantly in competition withPratt & Whitney for new engine designs required for civil and military aircraft. Utilizing theWright R-3350 Duplex-Cyclone as a basis, Wright developed a 22-cylinder engine, using R-3350 cylinders arranged as a two-row radial engine with 11 cylinders per row instead of 9.[1]
The air-cooled R-4090 was rated to deliver 3,000 hp (2,200 kW) at 2,800 rpm for take-off, from a total displacement of 4,092 cu in (67.06 L), with a compression ratio of 6.85:1. Improved performance was expected from the R-4090 if there had been further development. A two-speed single-stage supercharger helped maintain rated power to higher altitudes.[1]
The core of the engine was a forged steel crankcase which enclosed the three piece two-throw crankshaft. The cylinders were arranged equally around the crankcase, with each row off-set by 16.3636.° to ensure cooling airflow. Accessories similar to other Cyclone engines were arranged around the rear face of the crankcase and a 0.333:1 planetary reduction gearbox at the front.[1]
Although there are no records of failings of the R-4090, the engine was abandoned to allow development of the R-3350 Duplex-Cyclone series.[1]
Data from enginehistory.org,[2] Old Machine Press[1]
Related development
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