{{Short description|Aircraft gun mounting position}} [[File:Hs12 Ydrs.jpg|thumb|French Hispano-Suiza 12Y aircraft engine (cylinders removed) with Hispano-Suiza HS.404 engine gun mounted]] [[File:Bundesarchiv Bild 101I-390-1220-20, Russland, Flugzeug Me 109 des JG 54, Wartung.jpg|thumb|Luftwaffe soldier inspects the engine gun alignment of a Bf 109 fighter aircraft]] [[File:Daimler-Benz DB 605 showing crankshaft for motorkanone.jpg|thumb|Firing channel on a Daimler-Benz DB 605 for an engine gun.]] An '''engine gun''', or '''engine cannon''' (from {{langx|de|Motorkanone}}, "motor cannon"), is an aircraft gun mounted behind and through the cylinder block of an inline aircraft engine (most often a V engine) with a reduction drive that displaces the propeller axle to be in line with the gun so that gunfire is allowed through the propeller hub. This allows for nose-mounted weaponry on aircraft without the need for synchronization gear while also permitting higher calibers for nose-mounted weaponry, which otherwise would be hard to adapt for synchronization gear.<ref>{{cite web |title=PART V AUTOMATIC AIRCRAFT CANNON |url=https://www.ibiblio.org/hyperwar/USN/ref/MG/I/MG-5.html |website=ibiblio.org |access-date=2025-05-18}}</ref>
The first time this was done was during World War I when the French modified the Hispano-Suiza 8 engine to be able to install a 37 mm autocannon.<ref name="Thorsson 75">{{Cite book |last=Thorsson |first=Nils |title=Historik och kartläggning av vapenmateriel för flygplan |year=1975 |location=Arboga, Sweden |pages=25}}</ref> The concept was used widely before the Jet Age.
== Historical engine guns == === Finnish guns === * 12.7 mm VKT 12,70 LKk/42 (single use on a Morane-Saulnier MS.406)
=== French guns === * 7.5 mm MAC 1934 * 20 mm Hispano-Suiza HS.404 * 37 mm SAMC (''Semi Automatique Moteur Canon'')
=== German guns === * 7.9 mm MG 17 machine gun * 20 mm MG 151 cannon * 30 mm MK 103 cannon * 30 mm MK 108 cannon
=== Soviet guns === * 12.7 mm Berezin UB * 20 mm Berezin B-20 * 20 mm ShVAK cannon * 23 mm Nudelman-Suranov NS-23 * 37 mm Nudelman-Suranov NS-37 * 37 mm Nudelman N-37 * 45 mm Nudelman-Suranov NS-45
=== Swiss guns === * 20 mm Oerlikon FF
== Engine gun installations == [[File:Hispano-Suiza 8C (MAE).JPG|thumb|right|A geared-output shaft HS 8C engine for a SPAD S.XII WWI aircraft, showing the elevated intake manifold to clear the 37 mm cannon (shown to the right) mounted in the "V" between the cylinder banks.]]
=== French engines === * Hispano-Suiza 8 (various models) * Hispano-Suiza 12Y
=== German engines === * Daimler-Benz DB 603 * Daimler-Benz DB 605
=== Soviet engines === * Klimov M-105 * Klimov VK-106 * Klimov VK-107
=== Swiss engines === * Saurer YS-2 * Saurer YS-3
== Aircraft with engine guns ==
=== Czechoslovak aircraft === [[File:Bk-534.jpg|thumb|Czechoslovak Avia Bk-534, a biplane with a 20 mm engine gun]]
=== Finnish aircraft === * Mörkö Morane
=== French aircraft === [[File:SPAD S.XII NARA 55200258.jpg|thumb|French SPAD S.XII, a World War I aircraft with a 37 mm engine gun]]
* Dewoitine D.500 * Dewoitine D.520 * Loire-Nieuport LN.401 * Morane-Saulnier M.S.405 * Morane-Saulnier M.S.406 * Morane-Saulnier M.S.410 * Morane-Saulnier M.S.411 * Morane-Saulnier M.S.412 * Morane-Saulnier M.S.450 * SPAD S.XII
=== German aircraft === * Blohm & Voss BV 155 * Dornier Do 335 * Heinkel He 100 * Heinkel He 112 (''"kanonenvogel"'') * Messerschmitt Bf 109 * Focke-Wulf Fw 190 (D-12, D-13 Variants) * Focke-Wulf Ta 152
=== Italian aircraft === [[File:Fiat G.55 OR.jpg|thumb|Fiat G.55 Centauro with engine gun (MG 151/20)]]
* Fiat G.55 Centauro * Fiat G.56 * Macchi C.205 Veltro * Reggiane Re.2005 Sagittario * Savoia-Marchetti SM.92
=== Soviet aircraft === [[File:Yakovlev Yak-9K.jpg|thumb|Yakovlev Yak-9K with the 45 mm Nudelman-Suranov NS-45 engine gun mounted]]
* Lavochkin-Gorbunov-Gudkov LaGG-3 * Yakovlev Yak-1 * Yakovlev Yak-3 * Yakovlev Yak-7 * Yakovlev Yak-9
=== Swedish aircraft === * SAAB 23
=== Swiss aircraft === [[File:C-3604 in Dübendorf.jpg|thumb|Swiss EKW C-3604, an attacker with a 20 mm engine gun]] * C-35 * C-3603 * C-3604 * D-3800 * D-3801 * D-3802 * D-3803
=== Yugoslavian aircraft === * Ikarus S-49 * Rogožarski IK-3
== References == {{reflist}}
== External links == {{commonscat|Engine guns|position=left}}
Category:Aircraft guns Category:Engine guns