Final protective fire

Final protective fire is an immediately available barrier of direct and indirect fire designed to provide close protection to friendly positions and installations. It involves the concentration of weapons fire directly in front of the unit to impede enemy movement. An FPF request has absolute priority over any other kind of request.
The size of the FPF depends on the number and type of weapons firing. The supported maneuver commander designates the location of the FPF and it is adjusted into place by the Joint Forward Observer. Normally, the FPF is initiated 400 to 600 meters away from friendly units, and adjusted to within 200 to 400 meters of friendly positions and is integrated into the final protective line of the maneuver unit.
As the "final" in the name implies, it is the last resort in defensive plans, involving artillery integrated with small arms and heavy machine gun fire directed dangerously close to friendly defensive positions that are at risk of being overrun by the enemy.
Final protective fire is also commonly incorporated into a defensive plan that incorporates a final protective line, which is a line that, once the enemy has crossed, prompts the FPF plan to be enacted.
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