Editing Radial engine (section)

===Diesel radials===
[[File:Packard DR-980 USAF.jpg|thumb|Packard DR-980 diesel radial aircraft engine]]
[[File:Nordberg radial engine 648.JPG|thumb|A [[Nordberg Manufacturing Company]] two-stroke diesel radial engine for power generation and pump drive purposes]]

While most radial engines have been produced for gasoline, there have been diesel radial engines. Two major advantages favour [[diesel engine]]s — lower fuel consumption and reduced fire risk.{{Citation needed|date=October 2014}}

;Packard
Packard designed and built a 9-cylinder 980 cubic inch (16.06 litre) displacement diesel radial aircraft engine, the {{convert|225|hp|kW}} [[Packard DR-980|DR-980]], in 1928. On 28 May 1931, a DR-980 powered [[Bellanca CH-300]], with 481 gallons of fuel, piloted by [[Walter Edwin Lees]] and [[Frederick Brossy]] set a record for staying aloft for 84 hours and 32 minutes without being refueled.<ref>[http://www.enginehistory.org/Diesels/CH1.pdf Chapter 1: Development of the Diesel Aircraft Engine"] {{webarchive|url=https://web.archive.org/web/20120212213152/http://www.enginehistory.org/Diesels/CH1.pdf |date=2012-02-12 }} Aircraft Engine Historical Society — Diesels p.4 Retrieved: 30 January 2009.</ref> This record stood for 55 years until broken by the [[Rutan Voyager]].<ref>[http://www.aerofiles.com/chrono.html Aviation Chronology] Retrieved: 7 February 2009.</ref>

;Bristol
The experimental [[Bristol Phoenix]] of 1928–1932 was successfully flight tested in a [[Westland Wapiti]] and set altitude records in 1934 that lasted until World War II.{{Citation needed|date=October 2014}}

;Clerget
In 1932 the French company Clerget developed the 14D, a 14-cylinder [[two-stroke diesel engine|two-stroke diesel]] radial engine. After a series of improvements, in 1938 the 14F2 model produced {{convert|520|hp|kW|abbr=on}} at 1910 rpm cruise power, with a power-to-weight ratio near that of contemporary gasoline engines and a [[Brake specific fuel consumption|specific fuel consumption]] of roughly 80% that for an equivalent gasoline engine. During WWII the research continued, but no mass-production occurred because of the Nazi occupation. By 1943 the engine had grown to produce over {{convert|1000|hp|kW|abbr=on}} with a [[turbo-supercharger|turbocharger]]. After the war, the Clerget company was integrated in the [[SNECMA]] company and had plans for a 32-cylinder diesel engine of {{convert|4000|hp|kW|abbr=on}}, but in 1947 the company abandoned piston engine development in favour of the emerging turbine engines.{{Citation needed|date=October 2014}}

;Nordberg
The [[Nordberg Manufacturing Company]] of the United States developed and produced a series of large [[two-stroke engine|two-stroke]] radial diesel engines from the late 1940s for electrical production, primarily at [[aluminum]] smelters and for pumping water. They differed from most radials in that they had an even number of cylinders in a single bank (or row) and an unusual double master connecting rod. Variants were built that could be run on either diesel oil or gasoline or mixtures of both. A number of powerhouse installations utilising large numbers of these engines were made in the U.S.<ref>{{cite web|publisher=OldEngine|url=http://www.oldengine.org/members/diesel/Nordberg/Nordmenu.htm|title=Nordberg Diesel Engines|access-date=2006-11-20|archive-date=2018-09-19|archive-url=https://web.archive.org/web/20180919132942/http://www.oldengine.org/members/diesel/Nordberg/Nordmenu.htm|url-status=dead}}</ref>

;EMD
[[Electro-Motive Diesel]] (EMD) built the "pancake" engines 16-184 and 16-338 for marine use.<ref>{{cite web|url=https://oldmachinepress.com/2014/08/17/general-motors-electro-motive-16-184-diesel-engine/|title=General Motors / Electro-Motive 16-184 Diesel Engine|first=William|last=Pearce|date=18 August 2014|work=oldmachinepress.com|access-date=30 May 2016}}</ref>

;Zoche
[[Zoche aero-diesel]]s are a prototype radial design that have an even number of cylinders, either four or eight; but this is not problematic, because they are [[two-stroke engine]]s, with twice the number of power strokes as a four-stroke engine per crankshaft rotation.<ref>{{cite web|url=http://www.zoche.de|title=zoche aero-diesels homepage|work=zoche.de|access-date=30 May 2016}}</ref>{{third-party inline|date=November 2023}}