Wright Whirlwind series

{{Short description|Family of radial aircraft engines}}  {{infobox aero engine |name= Whirlwind series |image= Wright_J-6.jpg |caption= Partially sectioned [[Wright R-790|Wright J-4B]] at [[Canada Aviation Museum]] |engine_type= Air-cooled [[Radial engine|radial piston engine]] |manufacturer= [[Wright Aeronautical]] |national_origin= [[United States]] |first_run= |major_applications= |number_built = |developed_from = |developed_into = |variants_with_their_own_articles = }}

The '''Wright Whirlwind''' was a family of air-cooled [[radial engine|radial]] [[aircraft engine]]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 [[Radial engine#Multi-row radials|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]], a nine-cylinder air-cooled radial built by the [[Lawrance Aero Engine Company]] 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]]''' 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 [[supercharger]] was added to boost engine power and the cylinders were enlarged by expanding the [[Bore (engine)|bore]]. This family included three members: the nine-cylinder '''[[Wright R-975|R-975]]''', the seven-cylinder '''[[Wright R-760|R-760]]''', and the five-cylinder '''[[Wright R-540|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 [[armored fighting vehicles]] during [[World War II]].

During the mid-1930s, Wright also developed two fourteen-cylinder double-row versions of the Whirlwind, the '''R-1510''' of {{convert|600|hp|kW|abbr=on}}, and the '''R-1670''' of {{convert|800|hp|kW|abbr=on}}. These were used in a number of military aircraft prototypes, but neither engine reached the production stage.<ref>Curtiss-Wright (1940), p. 13</ref><ref>Curtiss-Wright (1983), p. 4-5.</ref>

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 Company|Continental Motors]], [[Hispano-Suiza]], and adapted for [[Soviet Union|Soviet]] government production by the [[Shvetsov]] [[OKB|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-4''' (1924){{sfn|McCutcheon|2023}} * 9-cylinder single row air cooled radial * Bore x stroke: {{cvt|4+1/2|x|5+1/2|in|mm|0}} * Displacement: {{cvt|787|cuin|L}}

'''[[Wright R-790|J-5 / R-790]]''' (1925){{sfn|McCutcheon|2023}}{{sfn|McCutcheon|2015}} * 9-cylinder single row air cooled radial * Bore x stroke: {{cvt|4+1/2|x|5+1/2|in|mm|0}} * Displacement: {{cvt|787|cuin|L}} * Power output: {{cvt|200|-|220|hp|kW}}

'''[[Wright R-540|J-6-5 / R-540]]''' (1928){{sfn|McCutcheon|2023}} * 5-cylinder single row air cooled radial * Bore x stroke: {{cvt|5|x|5+1/2|in|mm|0}} * Displacement: {{cvt|540|cuin|L}} * Power output: {{cvt|165|-|175|hp|kW}}

'''[[Wright R-760|J-6-7 / R-760]]''' (1928){{sfn|McCutcheon|2023}}{{sfn|Wilkinson|1945|p=159}} * 7-cylinder single row air cooled radial * Bore x stroke: {{cvt|5|x|5+1/2|in|mm|0}} * Displacement: {{cvt|758|cuin|L}} * Power output: {{cvt|240|-|350|hp|kW}}

'''[[Wright R-975|J-6-9 / R-975]]''' (1928){{sfn|McCutcheon|2023}}{{sfn|Wilkinson|1945|p=161}} * 9-cylinder single row air cooled radial * Bore x stroke: {{cvt|5|x|5+1/2|in|mm|0}} * Displacement: {{cvt|972|cuin|L}} * Power output: {{cvt|365|-|475|hp|kW}}

'''R-1510'''{{sfn|McCutcheon|2023}} * 14-cylinder twin-row air cooled radial * Bore x stroke: {{cvt|5|x|5+1/2|in|mm|0}} * Displacement: {{cvt|1512|cuin|L}} * Power output: {{cvt|680|-|700|hp|kW}}

'''R-1670'''{{sfn|McCutcheon|2023}} * 14-cylinder twin-row air cooled radial * Bore x stroke: {{cvt|5+1/4|x|5+1/2|in|mm|0}} * Displacement: {{cvt|1667|cuin|L}} * Power output: {{cvt|830|-|850|hp|kW}}

==See also== {{Aircontent |related= |similar engines= * [[Bristol Jupiter]] * [[Pratt & Whitney Wasp series]] |lists= * [[List of aircraft engines]] |see also= * [[Whirlwind Glaciers]] in [[Antarctica]] named after the Wright Whirlwind series<ref>{{Cite web |url=https://geonames.usgs.gov/apex/f?p=gnispq:5:::NO::P5_ANTAR_ID:16510 |title=USGS site |access-date=2019-03-29 |archive-date=2019-03-29 |archive-url=https://web.archive.org/web/20190329085914/https://geonames.usgs.gov/apex/f?p=gnispq:5:::NO::P5_ANTAR_ID:16510 |url-status=dead }}</ref> }}

==References== ===Citations=== {{reflist}}

===Bibliography=== * {{cite book |last= Gunston |first= Bill |title=World Encyclopedia of Aero Engines |year=1986 |publisher=Patrick Stephens |location= Wellingborough |pages=196–197 }} * {{Citation|title=Wright Engines - 1903 to 1940|url=https://www.enginehistory.org/Piston/Wright/WrightThrough1940.pdf|format=PDF|last=Curtiss-Wright|author-link=Curtiss-Wright|year=1940|access-date=January 4, 2022}}. Available from the Aircraft Engine Historical Society's [https://www.enginehistory.org/reference.shtml reference page]. * {{Citation|title=Historical Engine Summary (Beginning 1930)|url=https://www.enginehistory.org/Piston/Wright/C-WSpecsAfter1930.pdf|format=PDF|last=Curtiss-Wright|author-link=Curtiss-Wright|year=1983|access-date=January 4, 2022}}. Available from the Aircraft Engine Historical Society's [https://www.enginehistory.org/reference.shtml reference page]. * {{cite web |url=https://www.enginehistory.org/Piston/Before1925/EarlyEngines/W/Wac.shtml |title=Selected Early Engines W: Wright Aeronautical Corporation |last=McCutcheon |first=Kimble D. |date=August 28, 2023 |website=Aircraft Engine Historical Society, Inc |publisher= |access-date=September 7, 2024 }} * {{cite web |url=http://www.enginehistory.org/Piston/Wright/WrightJ-5.pdf |title=Wright J-5 “Whirlwind” |last=McCutcheon |first=Kimble D. |date=March 23, 2015 |website=Aircraft Engine Historical Society, Inc |publisher= |access-date=September 7, 2024 }} * {{cite book |last=Wilkinson |first=Paul H. |date=1945 |title=Aircraft Engines of the World 1945 |edition=Revised |location=New York |publisher=Paul H. Wilkinson }}

[[Category:Aircraft air-cooled radial piston engines]] [[Category:1920s aircraft piston engines]]