FM 17-98 SCOUT PLATOON

Target location
Following the type of mission, the method of target location is announced; this prepares the FDC to receive the data
sent by the observer and apply it to locate the target. The three methods for locating targets are grid, polar plot, and
shift from a known point. Only the polar plot and shift methods are initially announced to the FDC. If the observer
does not specify either polar or shift, the FDC knows the grid method is being used; the word "grid" is not announced
in the initial transmission. Example: "H24--THIS IS H67--FIRE FOR EFFECT--POLAR--OVER." (NOTE: The word
"grid" is announced at the beginning of a subsequent transmission calling for an adjustment of fires. Example: "H24--
THIS IS H67--ADJUST FIRE GRID 123445--OVER.")
Grid method. When using the grid method, the target location is normally sent in six digits (example: "180739"). The
direction from the observer to the target (in mils, if possible) must be given to the FDC after the call for fire, but
before the first adjusting rounds are shot.
Polar plot method. This method requires that the observer and the FDC know the observer’s exact location. The
observer determines the direction (to the nearest 10 mils) of the observer-target (OT) line and the distance (to the
nearest 100 meters) from his position to the target.
Shift from a known point method. This method can be used if the observer and the FDC have a common known
point. This point must have been previously established as an artillery target. To locate the target, the observer must
first determine the direction to the nearest 10 mils. If the observer has no compass, he can determine the direction by
using a map and protractor or by using his binocular reticle pattern and a known direction to the known point. He
should remember to apply the RALS rule (right add, left subtract) in determining direction to the target.
The observer then determines the lateral and range shifts. Lateral shifts are left or right from the known point to the
OT line and are given to the nearest 10 meters. Range shifts are given as "ADD" (when the target is beyond the known
point) or "DROP" (when the target is closer than the known point). Range shifts are given to the nearest 100 meters.
FM 6-30 explains in detail how to determine the lateral and range shifts.
Description of target, method of engagement, and method of fire and control
The observer includes these elements in his call for fire using the guidelines discussed in the following paragraphs.
Description of target. The observer describes the target to the FDC. The FDC then determines the type and amount of
ammunition needed. The target description should be brief yet accurate. This is the last required element in the call for
fire.
Method of engagement. The observer specifies how he wants to attack the target (type of ammunition, fuze, distance
from friendly troops). The FDC may change the ammunition type and/or fuze based on ammunition constraints. If the
target is within 600 meters of friendly troops, the observer announces "DANGER CLOSE" to supporting mortars and
artillery. When "DANGER CLOSE" is called, the initial rounds in adjustment should use a delay fuze.
Method of fire and control. The observer states who will give the command for fire to begin. If the observer wants to
control the time of firing, he will say, "AT MY COMMAND." The FDC will tell the observer when the unit is ready
to fire. At the proper time, the observer will say, "FIRE." If the observer does not say, "AT MY COMMAND," the
FDC will fire as soon as the platoon/battery is ready.
ADJUSTING INDIRECT FIRE
Once the call for fire has been made, the observer’s next concern is to ensure that the fire hits the target. If he can
locate the target accurately, he will request fire for effect in his call for fire. When the observer cannot accurately
locate the target for any reason (such as deceptive terrain, lack of identifiable terrain features, poor visibility, or an
inaccurate map), he must conduct an adjustment to get the fire on target. Normally, one artillery piece or mortar is
used in adjustment.
The observer must first pick an adjusting point. For a destruction mission (precision fire), the target is the adjusting
point. For an area target (area fire), the observer must pick a well-defined adjusting point at the center of the area or
close to it. The observer must spot the first adjusting round and each successive round and send range and deviation
corrections, as required, back to the FDC until fire hits the target. The observer spots by relating the burst or group of
bursts to the adjusting point. For a further discussion of adjusting mortar and artillery fire, see FM 6-30.