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 (the prototype
DC-1, the
DC-2, the first civil versions of the
DC-3, and the limited-production
DC-5), every wartime example of the
Boeing B-17 Flying Fortress and
Douglas SBD Dauntless bombers, the early versions of the
Polikarpov I-16 fighter (as the M-25), and the
Piasecki H-21 helicopter. The R-1820 also found limited use in armored vehicles. The G-200 variant developed at 2,300 rpm and powered the strictly experimental
M6 Heavy Tank.
D-200 Diesel The Wright R-1820 was converted to multi-fuel during World War II by
Caterpillar Inc. as the D-200 and produced at 2,000 rpm in the
M4A6 Sherman. ==Variants==