ATP-3-09-30 Observed Fires Download
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Chapter 7 7-4 ATP 3-09.30 28 September 2017 Figure 7-3. High angle fire 7-14. Generally, those weapons with a maximum elevation substantially in excess of 800 mils can fire high angle. All Army field artillery weapons are capable of low and high angle fires. Mortars are capable of only high angle fire. Naval guns are high muzzle velocity, flat trajectory weapons systems and are not suitable for high-angle fire. 7-15. The observer procedure for the adjustment of high-angle fire is the same as that for the adjustment of low angle fire. The observer must realize that small deviation corrections during adjustment may be unnecessary and time consuming because of the increased dispersion during high-angle fire. Since the time of flight is long in the adjustment and fire for effect, the FDC should announce SHOT and SPLASH. If an airburst is desired, fuze VT gives excellent results. FINAL PROTECTIVE FIRE 7-16. A final protective fire (FPF) is an immediately available prearranged barrier of fire designed to impede enemy movement across defensive lines or areas. The commander can only assign a single FPF to each firing unit, typically a battery or platoon. An FPF is a priority target for an element or system, and those fire units are laid on that target when they are not engaged in other fire missions. When the threat initiates the final assault into a defensive position, the defending unit initiates its FPFs to kill threat infantry soldiers and suppress armored vehicles. The size of the FPF depends on the number and type of weapons firing. Refer to JP 3-09.3 for more information regarding FPF. 7-17. The supported commander designates the location of the FPF. Plan the FPF to support a defense and integrate the FPF into the final protective line of the maneuver unit. The FPF may be any distance from the friendly position, but is normally within 200 to 400 meters (danger close) of friendly positions. The importance of accurate defensive fires and the danger close situation require that each weapon firing the FPF be adjusted into place, if possible. PROCEDURES 7-18. The FPF can be adjusted or non-adjusted. Considerations include the tactical implications of adjusting the FPF (loss of surprise) versus the accuracy required for firing close to friendly troops. MANUAL FDC 7-19. When an FPF with a manual FDC is established, the call for fire is similar to the normal call for fire in an adjust fire mission with the following exceptions: