action desired, such as delay, quick or time for the
FIRE DIRECTION CENTER-- The element of a
60-mm mortar.
command post, consisting of gunnery and
communication personnel and equipment, by means
GAS OPERATED-- The small-arms principle by which
of which the commander exercises fire direction and
gas pressure from a fired cartridge activates the
fire control.
operating parts of a weapon using a piston and
cylinder arrangement.
FIRE MISSION-- A target assigned to a unit or
personnel manning a certain weapon or weapons
GAS PORT-- A small hole drilled in the barrel to allow
with instructions as to the time and method of firing
the expanding gases to strike the piston in the
and placing fire on the target.
cylinder of a gas-operated weapon; sometimes
FIRE UNIT-- A unit whose fire is under the immediate
called a vent.
and effective control of one leader.
GENERAL SUPPORT-- The support given to a force
FIRING MECHANISM-- The parts of a weapon that
as a whole and not to any particular subdivision
move together to cause the cartridge primer to be
thereof.
struck when the trigger is depressed.
GRAZING FIRE-- Fire in which the trajectory does not
FIRING POSITIONS-- Defensive positions from
rise higher than the height of a man standing.
which fire missions are carried out; they are
GRENADE SUMP-- A circular hole large enough to
designated primary, alternate, or supplemental
accept the largest known enemy grenade; it slopes
FIXED FIRE-- Fire delivered on a point target.
downward under the fire step in the fighting hole.
Hand grenades thrown into the fighting hole are
FLANK-- The right or left extremity of a unit; the
exploded in this sump; their fragmentation is
element on the extreme right or left of the line; a
restricted to the unoccupied end of the fighting hole.
direction at right angles to the direction a unit is
facing.
GROOVES-- The depressed areas between the lands
(raised surfaces) in the bore; the cutaway portion of
FLANK GUARD-- A security detachment that protects
the rifling into which the jacket or rotating band of
the flank of a body of troops on the march.
a bullet fits to impart rotation to the bulletin its line
FLANKING FIRE-- Fire delivered at right angles to the
of flight.
enemy flank.
GROUND ZERO-- The point on the ground or directly
FLAT TRAJECTORY-- A trajectory having little or no
above at which a nuclear weapon has exploded.
curvature.
GROUP-- Two or more parts or assemblies that either
FORMATION-- Arrangement of the elements of a unit
function together in a gun or are so closely related
in line, in column, or in any other prescribed
to one another that they should be considered as a
manner.
unit.
FORWARD DEFENSE AREA-- Portion of a battle area
GUERRILLAS-- Combatants that are members of an
defended by front-line companies or platoons.
organized and recognized military force whose
activities normally are directed to harassing,
FORWARD SLOPE-- The slope of elevated terrain in
delaying, or disrupting opposing forces; they
the direction of the enemy.
normally wear civilian clothes.
FREQUENCY-- The band on which a unit is to operate
its radio communications.
GUIDE-- The individual (base) upon which a formation,
or an element thereof, regulates its march.
FRONT-- The line of contact of two opposing forces; the
length of space of an element or formation measured
HAMMER-- A lever that is swung around by spring
from one flank to the other; the direction of the
pressure to strike the firing pin of a weapon.
enemy.
HANGFIRE-- A delay in the functioning of a propelling
FRONTAL FIRE-- Fire delivered perpendicular to the
charge explosive train at the time of firing. In most
enemy (across his front).
cases the delay, though unpredictable, ranges from
a split second to several minutes.
FUZE-- A device for setting off an explosive charge; a
command or request to indicate the type of fuze
HEAD-- The leading element of a column.
AI-6
