upon an enemy penetration of an adjaent company or
platoon and to provide all-around defense.
Communication to the mortar platoon starts at the
Fire Direction Center (FDC). Companies requesting
a fire mission do so by contacting (FDC). The FDC
Assault squads, whose primary missions are to cover
will plot the fire mission and issue fire commands to
avenues of apprach to the FEBA, may be required to
the mortar section leader responsible for the mortar
prepare supplementary positions. The supplementary
gun crew. Forward observers (FOs) assigned to the
positions are to cover avenues into the flanks and rear of
mortar platoon communicate with the FDC directly.
the company. Assault squads support the defense by fire
FDC must seek approval for all fire missions from the
from planned supplementary positions when an armor
Fire Support Coordinator (FSC) located in the COC.
threat fails to develop.
Sectors of Observation
Sectors of observations are critical for mortar fire
Supplementary positions are infrequently
to be effective. The mortar platoon is not assigned a
established for a 60-mm mortar squad section.
sector of fire but must be able to provide coverage
However, fire within the battle area is planned to
throughout the battalion security area. Rifle platoon
provide for supporting frontline rifle units when they
commanders must ensure that their assigned battle
are forced to move to supplementary positions.
area is covered by overlapping sectors of observation.
Forward observers (FOs) from the mortar platoon are
usually assigned this task, but it may be necessary for
the rifle companies to assist the FOs. Personnel from
Once a machine gun team is deployed in a
the rifle companies assigned as FOs must be able to
defensive position and the gun laid, the squad leader
call in a fire mission and do so via the platoon
must ensure that range cards have been completed.
commander and the company CP.
Two sets of range cards must be made for every
fighting position. Range cards are very important and
Rate and Duration of Fire
are used for several purposes. The squad leader
forwards one copy as soon as possible to the platoon
In the absence of any instructions, the normal rate
commander. The platoon commander ensures the card
of fire is nine rounds per minute for the first 2 minutes
is accurate and then forwards it on to the company CP.
and six rounds per minute after that for the duration of
Range cards are the basis for the fire plan of the
final protective fire (FPF). The FDC chief will
company. All supporting fire, security sectors, and
normally specify the number of rounds to be expended
defensive coordination are planned using machine gun
on each target to the section leader. The COC, upon
fire as the base from which to build.
approval from the battalion commander, sets the
number of rounds to be fired for FPF. Consideration
The second copy of the range card will be kept by
the gun team. The card is used by members of the gun
support available, anticipated resupply schedule, area
team to fire at predetermined targets or to help in range
to be covered, and enemy activity.
estimations to other targets. Range cards may be
passed on to a relieving battalion. Patrols from
companies or other units may want to look at the range
cards to identify final protective lines. Patrols need to
Both the machine gun squad and the assault squad
know of any dead space to ensure that they are clear
may be positioned and employed in performing
of infiltrators and where to take cover during an FPF.
supplementary missions in defense.
COMPLETING A RANGE CARD
Range cards must be neat, clear, and prepared
Machine gun squads, employed on the FEBA or
using a universal format. Observe the range card
in the reserve area, prepare supplementary positions
from which to cover sectors of fire different from
and 4-18 as each component is explained below. (see
their primary sectors. Missions are usually based