page_title: Secondary armament
section_title: World War II
hierarchical_section_title: Secondary armament / World War II
caption_attribution_description: 5 inch turrets aboard USS Massachusetts (BB-59). Taken during refueling from the T3-S2-A1 class Kaskaskia (AO-27) during a storm at sea, 17 October 1944.
context_page_description: Secondary armament is a term used to refer to bevy smaller, faster-firing weapons that were typically effective at a shorter range than the main weapons on battleship- and cruiser-type warships. The nature, disposition, size and purpose of secondary weapons changed dramatically as the threat changed from torpedo boats, to torpedo-carrying destroyers, to aircraft, to anti-ship missiles.
context_section_description: With the emergence of the threat from air-delivered weapons, the nature of the secondary guns changed once more. Now they needed to be multi-purpose weapons, with a high-angle fire capability to engage aircraft, as well as the traditional use against destroyers. Although they were also used against capital ships, the extreme range of capital ship engagements (through superior optics and target prediction and, later, radar), meant they were not expected to achieve much.
  High angle weapons could not be mounted in casemates. Thus, they migrated to small turrets mounted on the upper deck. In order to hit a fast-moving air target, a high rate of fire was required, thus secondary guns reverted slightly to the 5-inch from 6-inch size. Although 6-inch guns were still used by several navies including France, Germany, Italy and Japan in their new battleships; they were complemented by 4 to 5-inch guns as well.
caption: USS Massachusetts 5-inch secondary gun battery (note the somewhat comical elevation angles demonstrated by the center and background turrets).
exif: {}