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On Colonial warships, a battery is a group of guns or missile launchers operated together at one place. A battery may vary in number and arrangement depending on class . In modern day naval nomenclature, a vessel's "main battery" is its primary offensive weapon.
The large turrets found on Colonial battlestars fire several types of ammunition, depending on the objective:
It should be noted that the massive recoil caused by firing these flak rounds makes it impossible for the cannon to have a fast rate of fire like the battlestar's point-defense turrets. These shells are also too large to be loaded quickly and efficiently by crew members, and as such are loaded by mechanical hoists (TRS: "33").
When engaging enemy targets over any kind of distance, a firing solution must be obtained. This requires several pieces of information to be input to a battery's fire-control computer, including the target's speed, course, and range; and the firing platform's speed and course. The velocity of the shells would be known, and is constant, given that there is no air friction in the vacuum of space. The resulting computation would allow the gun captains to accurately aim their weaponry to such a degree that firing will result in a probable hit.
Colonial gun batteries have several modes of operation.
At least on Galactica-type battlestars, the turrets appear to be manned and manually fired. Each battery has a transparent canopy through which it is occasional possible to make out two figures in colonial flight suits. Due to the location and the (almost certain) weaker nature of the transparent material of the canopy this is likely one of the most dangerous jobs on the ship, since the batteries tend to be prime targets for raiders. This destruction is usually explosive (owing to munitions detonating) and likely allows few options for escape (TRS: "Daybreak, Part II").
Close-in Weapon Systems
A close-in weapon system (CIWS) is a point-defense system used for engaging and eliminating enemy targets or weapons that have penetrated a Colonial warship's or station's defensive perimeter. Colonial CIWS are typically small caliber guns capable of high rates of fire, however some smaller Colonial warships use missile defense systems in place of defensive guns ("Blood & Chrome", TRS: "Miniseries").
These systems are placed along the hull of a warship or station to ensure a complete firing arc, leaving no angle open to attack. Colonial CIWS are further supplemented by Viper fighter support. Together, these defensive systems generally prove highly destructive to incoming enemy targets (TRS: "Miniseries").