Sorry for the delay in responding GG, i missed your most recent posts in the clutter.
"What is this FM 7-13"
My fault, i mistyped it's proper title. It's from FM 7-10(Infantry Rifle Company), chapter 7(Combat Support), part 13(Indirect Fires in Close Support), which i guess would make it FM 7-10-7-13?
http://www.globalsecurity.org/milita.../ch7.htm#c7p13
"7-13. INDIRECT FIRES IN CLOSE SUPPORT
Effective indirect fire support often requires artillery and mortar fires near our infantry soldiers. A safe integration of fires and maneuver this close demands careful planning, coordination, and knowledge of the supporting weapons. These close supporting fires are most commonly FPFs in a defensive operation and suppression/obscuration fires to support an assault on an enemy position. When planning these fires, the commander considers--
a. The Effect Required. In the defense, this may be to destroy enemy soldiers and to degrade the effectiveness of enemy vehicles by causing them to fight buttoned-up. In the attack, the suppression/obscuration of enemy positions to allow the breach and seizure of a foot hold on the objective is probably the desired effect.
b. The Accuracy of the Delivery System. There are many variables that impact on the accuracy of the weapon. The FSO has the technical knowledge to assist the commander. These weapons are area weapons systems; this means that every round fired from the same tube will impact in an area around the target or aiming point. This dispersion is greater in length than in width. The weather conditions (wind, temperature, and humidity), the condition of the weapon, and the proficiency of the crew also will affect the accuracy.
c. The Protection of his Unit as the Rounds are Impacting. If in well-prepared defensive positions with overhead cover, an FPF could be adjusted very close Oust beyond bursting range). If required, the CO could even call for artillery fires right on his company position using proximity or time fuses for air bursts. It is much more dangerous to call for close indirect fires during an attack. The CO considers the terrain, the breach site, and the enemy positions to determine how close to adjust his supporting indirect fires.
d. The Integration of Indirect Suppressive Fires. When integrating indirect suppressive fires to support the breach and assault, the following points are key:
(1) The danger increases with the size of the weapons. Use artillery to isolate the objective, use the battalion mortars on enemy positions away from the breach site, and use the 60-mm mortars, M203s, and direct fire weapons for close suppression.
(2) Safety is increased by assaulting perpendicular to the GT line. If the rounds are coming over the head of the assault element, the margin of safety is reduced.
(3) Company mortars firing direct lay or direct alignment are the most responsive system. They are able to observe the rounds impact and adjust accordingly. The safest method is when firing the 60-mm mortars with bipods.
(4) Ideally, the firing units will register prior to firing close-support missions. If not, the first rounds fired may be off target by a considerable distance. Once the firing units are adjusted on a target, then any shifts from that target are much more reliable.
e. Timings and Control. The final requirement for integrating these fires is to establish timings and control to ensure these targets are initiated, adjusted, and shifted properly. If possible the company FSO should locate where he can observe these targets (possibly with the support element). A detailed execution matrix that assigns responsibility for each target to the leader or FO who is in the best position to control them should be developed. These soldiers must know when each target/series/group is fired, what effect is desired on which enemy positions, and when to lift or shift the fires. Consider the use of pyrotechnic or other signals to ensure communication."