Ship gun fire-control system

Ship gun fire-control systems (GFCS) are analogue fire-control systems that were used aboard naval warships prior to modern electronic computerized systems, to control targeting of guns against surface ships, aircraft, and shore targets, with either optical or radar sighting. Most US ships that are destroyers or larger (but not destroyer escorts except Brooke-class DEGs later designated FFGs or escort carriers) employed gun fire-control systems for 5-inch (127 mm) and larger guns, up to battleships, such as Iowa class.

Source: Wikipedia — Ship gun fire-control system (CC BY-SA 4.0)