fire direction center

In the land-based field artillery, the field artillery team is organized to direct and control indirect fire artillery fire on the battlefield. Since World War I, to conduct indirect artillery fire, three distinct components have evolved in this organization, the forward observer (or FO), the fire direction center (FDC) and what is called the gun line (the actual guns themselves). On the battlefield, the field artillery team will be comprised of some combinations of all of the these elements. In other words there may be multiple FOs calling in fire on multiple targets to multiple FDCs and any component may be in communication with some of the other elements depending on the situational requirements.
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