The Wright Whirlwind was a family of air-cooled radial

aircraft engine An aircraft engine, often referred to as an aero engine, is the power component of an aircraft propulsion system. Most aircraft engines are either piston engines or gas turbines, although a few have been rocket powered and in recent years many ...

s built by Wright Aeronautical (originally an independent company, later a division of Curtiss-Wright). The family began with nine-cylinder engines, and later expanded to include five-cylinder and seven-cylinder varieties. Fourteen-cylinder twin-row versions were also developed, but these were not commercially produced. The Whirlwind series was succeeded by more powerful but still air-cooled radial aero engines, notably the Pratt & Whitney Wasp series and the Wright Cyclone series.

Description

The Whirlwind was a direct descendant of the

Lawrance J-1 The Lawrance J-1 was an engine developed by Charles Lanier Lawrance and used in American aircraft in the early 1920s. It was a nine-cylinder, air-cooled radial design. Development During World War I the Lawrance Aero Engine Company of New Yor ...

, a nine-cylinder air-cooled radial built by the

Lawrance Aero Engine Company Lawrance Aero Engine Company was an American aircraft engine manufacturer. Founded by engine pioneer Charles Lawrance, it designed one of the first successful air-cooled radial engines. It existed for only 5 years, being acquired by Wright Aeronau ...

for the U.S. Navy. Because the Navy was very enthusiastic about air-cooled radials, but was concerned that Lawrance could not produce enough engines for its needs, it forced Wright to purchase the Lawrance company in 1923 and build the J-1 itself. Wright's J-1 was the first engine in its nine-cylinder

R-790 Whirlwind The Wright R-790 Whirlwind was a series of nine-cylinder air-cooled radial aircraft engines built by Wright Aeronautical Corporation, with a total displacement of about and around . These engines were the earliest members of the Wright Whirlwi ...

series and was quickly followed by the J-3, J-4, J-4A, J-4B, and finally the popular and successful J-5 of 1925. In 1928, Wright replaced the R-790 series with the J-6 Whirlwind family, in which a

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was added to boost engine power and the cylinders were enlarged by expanding the

bore Bore or Bores often refer to: *Boredom * Drill Relating to holes * Boring (manufacturing), a machining process that enlarges a hole ** Bore (engine), the diameter of a cylinder in a piston engine or a steam locomotive ** Bore (wind instruments), ...

. This family included three members: the nine-cylinder R-975, the seven-cylinder R-760, and the five-cylinder R-540, providing a range of different power levels using the same basic design. Of these, the R-975 proved the most popular, especially because of its use in

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during

World War II World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposin ...

. During the mid-1930s, Wright also developed two fourteen-cylinder double-row versions of the Whirlwind, the R-1510 of , and the R-1670 of . These were used in a number of military aircraft prototypes, but neither engine reached the production stage. Air-cooled Whirlwinds were lighter and more reliable than liquid-cooled engines of similar power, since a liquid cooling system added weight and required extra maintenance. Thanks to these advantages Whirlwind engines were used widely and were built in large numbers. Licensed copies were produced by manufacturers such as Continental Motors,

Hispano-Suiza Hispano-Suiza () is a Spanish automotive–engineering company. It was founded in 1904 by Marc Birkigt and Damian Mateu as an automobile manufacturer and eventually had several factories in Spain and France that produced luxury cars, aircraft en ...

, and adapted for

Soviet The Soviet Union,. officially the Union of Soviet Socialist Republics. (USSR),. was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 to 1991. A flagship communist state, ...

government production by the Shvetsov OKB-19 design bureau. The Whirlwind's success led to the development of other air-cooled radial engines throughout the 1920s, 1930s, and 1940s.

Whirlwind series

* J-5 / R-790: 9-cylinder radial, . Produced 1923-1928. * J-6-5 / R-540: 5-cylinder radial, . Produced 1928-1937. * J-6-7 / R-760: 7-cylinder radial, . Produced 1928-1945. * J-6-9 / R-975: 9-cylinder radial, . Produced 1928-1950s. * R-1510: 14-cylinder twin-row radial, . Introduced 1933, prototypes only. * R-1670: 14-cylinder twin-row radial, . Introduced 1934, prototypes only.

References

* * . Available from the Aircraft Engine Historical Society'
reference page
* . Available from the Aircraft Engine Historical Society'
reference page
{{US military piston aeroengines Aircraft air-cooled radial piston engines 1920s aircraft piston engines

Description

Whirlwind series

See also

References