base pads

A fire support base (FSB, firebase or FB) is a temporary military facility used to provide fire support (often in the form of artillery) 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 continues to be used in military operations. Under the original concept of the artillery fire support base, a 6-gun battery was 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 five 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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