Fire support base

A fire support base (FSB, firebase or FB) is a temporary military encampment to provide artillery fire support to infantry operating in areas beyond the normal range of fire support from their own base camps. FSBs follow a number of plans; their shape and construction varying based on the terrain they occupy and the projected garrison.

Widely used during the Vietnam War, the concept has continued on through current military operations including in Afghanistan.

A fire support base was originally a temporary firing base for artillery, although many evolved into more permanent bases. Their main components varied by size: a typical FSB usually had a battery of six 105 millimeter or 155 mm howitzers, a platoon of engineers permanently on station for construction and maintenance projects, at least two landing pads for helicopters (a smaller VIP pad and at least one resupply pad), a Tactical Operations Center (TOC), an aid station staffed with medics, a communications bunker, and a company of infantry serving as the defense garrison. Large FSBs might also have 2 artillery batteries, and an infantry battalion. Under the original concept of the artillery fire support base, a 6-gun battery set up with one howitzer in the center to fire illumination rounds during night attacks and serve as the base's main registration gun. The other 5 howitzers were arranged around it in a "star" pattern. Smaller FSBs tended to vary greatly from this layout, with two to four howitzers of various calibers (usually 105 mm and 155 mm at battalion level) located in dispersed and fortified firing positions. These smaller bases arranged their guns in square or triangle patterns when possible.

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