{{Infobox weapon |name=Davis Gun |image= Davis gun NARA-45523875.jpg |caption=Davis gun mounted on Curtiss F5L anti-submarine seaplane |origin= United States |type= Recoilless cannon <!-- Type selection --> |is_ranged= |is_bladed= |is_explosive= yes |is_artillery= yes |is_vehicle= |is_missile= |is_UK= yes <!-- Service history --> |service= |used_by=Royal Naval Air Service |wars=World War I <!-- Production history --> |designer= Cleland Davis |design_date=1912–1914 |manufacturer= |unit_cost= |production_date= |number= |variants= |spec_label= |weight= |length= |part_length= <!-- Ranged weapon specifications --> |cartridge= |caliber= |barrels= |action= |rate= |velocity= |range= |max_range= |feed= |sights= <!-- Artillery specifications --> |breech= |recoil= |carriage= <!-- Explosive specifications --> |filling_weight= }} The '''Davis gun''' was the first true recoilless gun developed and taken into service. It was developed by Commander Cleland Davis<ref name=Williams>{{cite web |title=The Cannon Pioneers: The early development and use of aircraft cannon |first=Anthony G |last=Williams |url=https://quarryhs.co.uk/cannon_pioneers.htm |date=August 2014 |accessdate=28 December 2021 |archive-date=28 December 2021 |archive-url=https://web.archive.org/web/20211228103039/https://quarryhs.co.uk/cannon_pioneers.htm |url-status=dead }}</ref> of the United States Navy in 1910, just prior to World War I.
==Development== thumb|upright|Different types of Davis-type ammunition<ref>{{Cite book |url=https://archive.org/details/ammunitioninstru00unit |title=Ammunition : instructions for the naval service, 1923 |last=United States. Navy Dept. Bureau of Ordnance |date=1923 |publisher=Government Printing Office |location=Washington, D.C. |pages=162}}</ref> Davis' design connected two guns back to back, with the backwards-facing gun loaded with lead balls and grease of the same weight as the shell in the other gun, acting as a counter. His idea was used experimentally by the British and Americans as an anti-Zeppelin and anti-submarine weapon<ref name=ordanance>{{cite web|title=DAVIS AMMUNITION|url=http://www.big-ordnance.com/Davis/davis_ammunition.htm|publisher=www.big-ordnance.com|accessdate=19 November 2012|archive-date=22 November 2011|archive-url=https://web.archive.org/web/20111122005615/http://www.big-ordnance.com/Davis/davis_ammunition.htm|url-status=dead}}</ref> mounted on the British Handley Page O/100 and O/400 bombers and the American Curtiss Twin JN<ref name=Williams/> and Curtiss HS-2L and H-16 flying boats. The direct development of the gun ended with the end of World War I in November 1918, but the firing principle has been copied by later designs.
==Description== The gun was made in three sizes: 2-pounder, 6-pounder and 12-pounder; {{convert|1.57|in|mm|abbr=on}}, {{convert|2.45|in|mm|abbr=on}},<ref>Williams give 57mm calibre</ref> and {{convert|3|in|abbr=on}} in caliber respectively, firing {{convert|2|lb|kg|adj=on}}, {{convert|6|lb|kg|adj=on}}, and {{convert|12|lb|kg|adj=on}} shells. The 3-inch gun carried a pressure of 15 tons per square inch (2,109 kg per cm<sup>2</sup>) when fired.<ref name=navweap>{{cite web |title=United States of America Experimental and Miscellaneous 3" (7.62 cm) Guns |url=http://www.navweaps.com/Weapons/WNUS_3-15_mk12.htm |publisher=www.navweaps.com|access-date=19 November 2012}}</ref> Usually a Lewis machine gun was mounted on top of the Davis gun's barrel for use in sighting and as an auxiliary and anti-aircraft weapon.
==Aircraft used== The gun was tested on various aircraft and some aircraft were designed to carry the gun: *Airco DH.4 *Armstrong-Whitworth FK.5 and FK.6 - "escort fighter" triplane *Curtiss F5L - patrol flying boat used by US Navy *Felixstowe Porte Baby - large flying boat *Handley-Page O/100 - twin engined bombers with 6pdr Davis gun added for ground attack and anti-submarine *Handley-Page O/400 - larger version of the O/400 *Naval Aircraft Factory N-1 - patrol floatplane designed by US Navy, four prototypes built, project canceled<ref>{{cite book |last=Trimble |first=William F. |date=1990 |title=Wings for the Navy: A History of the Naval Aircraft Factory, 1917-1956 |edition=1st |location=Annapolis, Maryland |publisher=Naval Institute Press |isbn=0-87021-663-5 |pages=35–36}}</ref> *Short Type 184 *Short 310-B seaplane *Pemberton-Billing PB.29E *Pemberton-Billing PB.31E - long endurance anti-Zeppelin night fighter with 37mm Davis gun, prototypes only *Robey-Peters RRF.25 Gun-carrier - two Davis guns. Single prototype for Royal Navy completed
==Surviving examples== There are examples at the Naval Aviation Museum at Pensacola, Florida, the Imperial War Museum in London, and the Kentucky Historical Society in Frankfort, Kentucky.{{cn|date=December 2021}}
==See also== *COW 37 mm gun
==References== {{reflist}}
==Bibliography== *{{cite journal |last1=Russell |first1=Mark |title=Bring Out the Big Guns: British Military Aviation & the Development of the Heavy Cannon, 1914–39|journal=The Aviation Historian |date=2019 |issue=28 |pages=60–69 |issn=2051-1930}}
==External links== * [https://patentimages.storage.googleapis.com/89/b3/78/0613b1559cdfd7/US1108714.pdf Patent 1108714] * [https://patentimages.storage.googleapis.com/9e/aa/f6/a9eb4cd8069295/US1108717.pdf Patent 1108717] {{DEFAULTSORT:Davis Gun}} Category:Recoilless rifles of the United States Category:World War I aircraft guns