Wright R-1820 Cyclone


The Wright R-1820 Cyclone 9 is an American radial engine developed by Curtiss-Wright, widely used on aircraft in the 1930s through 1950s. It was produced under license in Spain as the Hispano-Suiza 9V or Hispano-Wright 9V, and in the Soviet Union as the Shvetsov M-25.

Design and development

The R-1820 Cyclone 9 represented a further development of the Wright P-2 engine dating back to 1925. Featuring a greater displacement and a host of improvements, the R-1820 entered production in 1931. The engine remained in production well into the 1950s.
The R-1820 was built under license by Lycoming, Pratt & Whitney Canada, and also, during World War II, by the Studebaker Corporation. The Soviet Union had purchased a license for the design, and the Shvetsov OKB was formed to metricate the American specification powerplant for Soviet government-factory production as the M-25, with the R-1820's general design features used by the Shvetsov design bureau for many of their future radials for the Soviet air forces through the 1940s and onwards. In Spain the R-1820 was license-built as the Hispano-Suiza 9V or Hispano-Wright 9V.
The R-1820 was at the heart of many famous aircraft including early Douglas airliners, every wartime example of the Boeing B-17 Flying Fortress and Douglas SBD Dauntless bombers, the early versions of the Polikarpov I-16 fighter, and the Piasecki H-21 helicopter.
The R-1820 also found limited use in armoured vehicles. The G-200 variant developed at 2,300 rpm and powered the M6 Heavy Tank.

D-200 Diesel

The Wright RD-1820 was converted to a diesel during World War II by Caterpillar Inc. as the D-200 and produced at 2,000 rpm in the M4A6 Sherman.

Variants

Notes: Unit numbers ending with W indicate engine variants fitted with water-methanol emergency power boost systems.

Hispano-Suiza 9V

The Hispano-Suiza 9V is a licence-built version of the R-1820.
;Hispano-Suiza 9Vr:9V with reduction gear
;Hispano-Suiza 9Vb:
;Hispano-Suiza 9Vbr:variant of the 9Vb with reduction gear
;Hispano-Suiza 9Vbrs:variant of the 9Vb with reduction gear and supercharger
;Hispano-Suiza 9Vbs:variant of the 9Vb with supercharger
;Hispano-Suiza 9Vd:variant of the 9V
;Hispano-Suiza 9V-10: driving fixed-pitch propeller
;Hispano-Suiza 9V-11:as -10 but RH rotation
;Hispano-Suiza 9V-16: driving variable-pitch propeller, LH rotation
;Hispano-Suiza 9V-17:as -16 but RH rotation

Applications

Vehicles

Preserved Wright R-1820 engines are on display at the following museums: