View source for Straight-twelve engine

{{Short description|Inline piston engine with twelve cylinders}}
[[File:Wolseley 12 cylinder 360hp petrol or oil marine engine (Rankin Kennedy, Modern Engines, Vol III).jpg|thumb|A 1905 [[The Wolseley Tool and Motor Car Company|Wolseley]] straight-12, 360&nbsp;hp, petrol or oil marine engine]]
A '''straight-12 engine''' (also known as a '''inline-12 engine''') is a twelve-cylinder [[piston engine]] with all twelve [[cylinder (engine)|cylinders]] mounted in a straight line along the [[crankcase]].

==Land use==
Due to the very long length of a straight-twelve engine, they are rarely used in automobiles. The first known example is a {{convert|7.2|L|cuin}} engine in the 1920 French ''Corona'' car;<ref name="Encyclopedia">{{cite book|last1=Burgess Wise|first1=David|title=The Illustrated Encyclopedia of Automobiles|date=1979|publisher=New Burlington Books|isbn=0-906286-16-6|page=131}}</ref> however it is not known if any cars were sold. [[Packard]] also experimented with an automobile powered by an inline 12 in 1929.<ref>{{cite web|url=https://theoldmotor.com/?p=134254|title=The Long-Lost Experimental Packard Straight Twelve |website=The Old Motor|date=4 December 2014}}</ref>

The straight-12 has also been used for large military trucks.{{citation needed|date=December 2022}}

==Marine use==
Some Russian firms built straight-12s for use in ships in the 1960s and 1970s.

MAN Diesel & Turbo 12K98ME and 12S90ME-C and the [[Wärtsilä-Sulzer RTA96-C]] are examples of contemporary marine engines in L-12-cylinder configuration. These are popular for propulsion in container ships.<ref>{{Cite web |url=https://www.dieselarmy.com/tech/engine/worlds-biggest-diesel-series-mans-record-breaking-12s90me-c/ |title=World's Largest Diesel: MAN's Record-Breaking 12S90ME-C |first=Stuart |last=Bourdon |date=9 March 2015 |access-date=2017-05-31 |archive-date=2017-06-14 |archive-url=https://web.archive.org/web/20170614205550/http://www.dieselarmy.com/engine-tech/engine/worlds-largest-diesel-series-mans-record-breaking-12s90me-c/ |url-status=live}}</ref><ref>{{Cite web |url=http://marine.man.eu/docs/default-source/shopwaredocuments/marine-engine-programme-2217.pdf |title=Marine Engine IMO Tier ll and Tier lll Programme 2017 |access-date=2017-05-31 |archive-date=2017-05-17 |archive-url=https://web.archive.org/web/20170517065155/http://marine.man.eu/docs/default-source/shopwaredocuments/marine-engine-programme-2217.pdf |url-status=dead}}</ref>

==References==
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{{Piston engine configurations}}

[[Category:Piston engine configurations|Straight-12]]
[[Category:12-cylinder engines]]
[[Category:Straight engines|12]]

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