In modern usage the term “gunship” refers to fixed-wing aircraft having laterally-mounted heavy armaments (i.e. firing to the side) to attack ground or sea targets. These gunships are configured to circle the target instead of performing strafing runs. Such aircraft have their armament on one side harmonized to fire at the apex of an imaginary cone formed by the aircraft and the ground when performing a pylon turn (banking turn). The term “gunship” originated in the mid-19th century as a synonym for gunboat and also referred to the heavily armed ironcladsteamships used during the American Civil War.
The term helicopter gunship is commonly used to describe armed helicopters.
During 1942 and 1943, the lack of a usable escort fighter for the United States Army Air Forces in the European Theatre of Operations led to experiments in dramatically increasing the armament of a standard Boeing B-17F Flying Fortress, and later a single Consolidated B-24D Liberator, to each have 14 to 16 Browning AN/M2 .50 cal machine guns as the Boeing YB-40 Flying Fortress and Consolidated XB-41 Liberator respectively. These were to accompany regular heavy bomber formations over occupied Europe on strategic bombing raids for long-range escort duties as “flying destroyer gunships”. The YB-40 was sometimes described as a gunship, and a small 25-aircraft batch of the B-17-derived gunships were built, with a dozen of these deployed to Europe; the XB-41 had problems with stability and did not progress.