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79 Cards in this Set

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FO duties (4):
Forward observer:
1. Detects and locates suitable targets
2. Calls for fire
3. Adjusts fire
4. Relays the results of his fire missions
Fire direction center (FDC) 3:
• Receives the CFF from the FO
• Computes firing data
• Then transmits that data in the form of weapon settings and fire commands to the firing unit
Call for Fire
Degrees may be converted to mils by multiplying
the number of degrees by
Mil Relation Formula
The mil relation formula states that an angle of one mil equates to one meter of lateral distance for every 1000 meters of range.

W=(Range/1000)*("M" angular deviation)
Observer-Target (OT) Direction
The azimuth from the FO to the
target. OT direction is always expressed to the nearest 10 mils grid and transmitted with four digits.
The lensatic compass has an accuracy of __. The FO reads mils magnetic from the compass and then converts to __ __ by applying the __ __.
of +/- 50 mils
mils grid GM angle.
LATERAL ADJUSTMENTS on the M22 BINOCULARS are computed on the:
horiztonal scale
Polar Plot (a) definition
(b) primary advantage (c) primary disadvantage
(a) FO describes the target location in relation to his position. (b) fast and can be
done without a map (c) first
transmitted to the firing unit
Polar Plot steps (3):
1 FO determines his location and transmits it to the FDC prior to the CFF in the form of a POSREP.
2 Determine the OT direction to the nearest 10 mils grid.
3 Determine the distance to the target to the nearest 100 meters.
Grid Coordinates method recommended when FO (a) The firing unit __ __(b) have to know the FO's position. The FO locates the target to an accuracy of (c).
(a) has conducted a thorough terrain/map study (b) does not (c) 100 meters (six digit grid)
Shift From a Known Point advantages (3)
1. o It is accurate.
2. It does not require the use of a map.
3. The firing unit does not need to know the FO’s location.
Shift From a Known Point disadvantages (2)
the firing unit must know the location of the (1) known (terrain reference) point that was previously reported
(2) Target that was previously fired on and recorded
Shift from a known point method steps
1 Select the known point to be used and identify it in the CFF.
2 Determine the OT direction to the nearest 10 mils.
3 Determine the “lateral shift” (W) to the nearest 10 meters: w=(r/1000)(M)
4 Transmit the “lateral shift” in the CFF as a “left” or “right” with meters
5 Determine the “range shift” between the known point and the target to the
6 Transmit the “range shift” in the CFF as • An “add” if the target is at a greater distance than the known point • A “drop” if the target is at a lesser distance.
(1) Observer identification
(2) Warning order
(3) Target location
(4) Target description
(5) Method of engagement
(6) Method of fire and control
Type of Mission: Adjust Fire (3)
1 Announced when the FO decides that an adjustment is needed because of questionable target location
2 One gun fires one round at a time until the round is close enough for the entire firing unit to engage the target.
3 Avoids wasted ammunition, but may allow the enemy time to leave the target area or seek cover
Type of Mission: Fire for effect(3)
• Announced when the FO has an accurate target location and is certain that the first volley will have an effect on the target
• All guns of the firing unit fire simultaneously
• FO should strive for first round fire for effect
Target Description (4):
1 Type of target (troops, supply dump, trucks)
2 Target activity (digging in, assembly area)
3 Number of elements in the target (squad, three trucks)
4 Degree of protection (in the open, in fighting holes, in bunkers with overhead cover)
Method of Engagement (a) definition and options (b)
(a) Method of engagement is the element that the FO uses to describe the attack of the target.
(b) Danger close” and “Ammunition”
Danger Close” is included when the predicted impact of: 2-4-6
o A 60mm mortar is within 200 meters of friendly troops
o An 81mm mortar is within 400 meters of friendly troops
o An artillery round is within 600 meters of friendly troops
The standard type of ammunition is
The term, “in effect" is used to (2):
• Indicates that the projectile/fuze specified is desired during the fire for effect phase
• Is only included in an “Adjust Fire” mission
Illumination, ICM, and M825 (“Felt Wedge”)/Smoke can only be fired with __ __. Therefore, when firing these projectiles, fuze time is understood and need not be specified.
fuze time
“HE” (High explosive) Fuze “PD” (Point detonating) or “Q” (Quick)
of Fire and Control are suitable for (3):
1 Adjust fire
2 Personnel in open
3 Unarmored vehicles
“HE” (High explosive) Fuze “Delay” suitable for (5):
1 Targets in heavy trees
2 Bunkers
3 Earth/log emplacements
4 Adjusting FPF
5 Danger close
“HE” (High explosive) Fuze “VT” (Variable time)
“Time” (Mechanical time) suitable for (3):
1 Personnel in open
2 Personnel in trenches
3 Light armored vehicles
“WP” (White phosphorous)Fuze • “PD” • “Time”
adjustment (4):
1 Incendiary
2 Marking
3 Screening/obscuring
4 POL/ammo
Illum” (Illumination) Fuze (Time understood)(2):
1 On the deck” (Marking)
2 Illumination
“ICM” (Improved conventional munitions) Fuze (Time understood)(2):
1 Area personnel targets
2 Armored vehicles
“Smoke” (M825 improved smoke)Fuze (Time understood)(2):
1 Screening
2 Obscuring
Method of fire
Not used at TBS, method of fire is an advanced technique that allows the FO to control the specific weapon and sequence of firing during adjustment and fire for effect.
Method of control
In the absence of a specified method of control, fire missions are executed “When Ready.” Two other options you may use at TBS are “At My Command (AMC) and Time on Target (TOT).”
The Message to Observer (MTO) steps (5):
1 After receiving the Call For Fire (CFF), Fire Direction Center (FDC) determines how the target will be attacked
2 The FDC’s decisions are announced to the FO in the form of an MTO, which the FO reads back.
3 The MTO should be sent to the FO before the first correction is made.
4 The FO reads the MTO back to the FDC verbatim.
5 In this MTO, the artillery battery will fire the adjusting rounds, and the artillery battalion will fire
for effect.
MTO will contain (4):
1 Unit(s) to fire
2 Changes to the call for fire
3 Number of rounds
4 Target number
There are three reports that will be sent by the FDC during a fire mission.
1 Shot
2 Splash
3 Spottings
The firing unit will transmit “Shot” after each round fired in adjustment and the initial round in the fire for effect phase
The FO acknowledges each. Example.
FDC: Shot, over.
FO: Shot, out.
When requested, the transmission of “Splash” by the FDC informs the FO
when his round is five seconds from detonation. When reported, “Splash” should be
transmitted for each round in adjustment and the initial round in each volley of the fire for effect.
A spotting is the FO’s mental determination of the location of the burst relative to the target. Spottings are recorded, but not announced. Spottings must be made the instant that the burst occurs, except where deliberately delayed to take advantage of drifting smoke or dust.
Spottings are made for
o Range, to determine how far a burst is beyond or short of the target
o Deviation, to determine how far a burst is to the right or left of the OTL
The FO should position his binoculars for spotting before the burst appears by holding the binoculars just __ __ __, looking over the top of them with the naked eye until the burst is sighted. Then raise the binoculars to eye level and makes the spotting.
below eye level
Range Spotting
1 Over:
2 Short:
3 Range correct:
4 Range doubtful:
1 Round detonates beyond the target
2 Round detonates between the FO and the target
3 Round detonates at the same range as the target
4 Round detonates so far to the right or left of the OTL that a definite range spotting cannot be made
The three possible deviation spottings are:
1 On line: Round detonates along the OTL
2 (# of mils) left: Round detonates to the left of the OTL
3 (# of mils) right: Round detonates to the right of the OTL
After recording a spotting, the FO determines a correction to move the next round onto the target. Corrections are sent in
1 Meters
2 Reverse order of the spotting: deviation followed by range
Sequence of Subsequent Corrections (10)
1 Direction
2 Danger close
3 Shell
4 Fuze
5 Deviation
6 Range
7 Target description
8 Change in type of mission/control
9 Splash
10 Repeat
__ precedes all other subsequent corrections when announced.
Deviation corrections steps
1 Determine the observer-target (OT) factor. The OT factor is based on the mil relation formula and is defined as the OT distance divided by 1000.
2 Multiply the deviation spotting by
the OT factor. Express to the
nearest 10 meters with the
minimum correction being 30.
The direction of the deviation correction is opposite that of the spotting. The computed deviation correction is announced as “left” or “right” followed by the number of meters.
Successive bracketing
The FO continues this process until a 100-meter bracket is established around the target. He then adds or drops 50 (with a deviation correction as required) and enters the fire for effect phase.
Range Bracketing Guide - OT Distance (in meters) 0 – 1000
Add/drop 100
Range Bracketing Guide - OT Distance (in meters) 1000 – 2000
Add/drop 200
Range Bracketing Guide - OT Distance (in meters) Greater than 2000
Add/drop 400
Entering Fire for Effect. The fire for effect phase is entered (2)
1 When the deviation and range are correct
2 If effective fire will result when the range bracket is split
The FO specifically enters the fire for effect phase when (2)
1 An adjusting round has an effect on the target
2 Splitting a 100-meter bracket
To enter the fire for effect phase, the FO announces, “__ __ __,” preceded by any corrections.
Fire for effect
If additional fire is needed, the FO announces, “Repeat.” The term, “Repeat,” indicates the FO’s desire to use the same volume of fire.
Adjust the Point of Impact
If the location of the fire for effect needs to be moved to achieve satisfactory results, the FO
• Announces the appropriate corrections (refinement) and “Repeat”
• May reenter adjust fire
Ending a Fire Mission - items included (4):
1 Refinement
2 Record as target
3 End of mission
4 Surveillance
If fires have been inaccurate but have produced sufficient results, the FO transmits a refinement to the FDC. Refinements are sent in increments of 10 meters and may be less than 30 meters.
Record as Target
If the FO wants the target to be plotted for future use, he announces, “Record as target.” The FDC:
o Applies the refinement
o Conducts a replot, when necessary
o Announces the adjusted grid to the target
The target number will be the same target number that was provided in the MTO.
End of Mission
“End of mission” followed by surveillance is the last transmission in the course of the fire mission. Once it has been announced, the mission is considered to be terminated.
Surveillance should be brief but should provide casualty and/or damage information as accurately as possible. This requires the correct usage of “destroyed,” “neutralized,” and “suppressed.”
Suppressive fires are delivered as 2:
1 An immediate suppression mission: used to fire on a planned target or target of opportunity that has taken friendly units under fire.
2 A suppression mission: used to fire on a planned target that is not currently active.
Immediate Suppression
An immediate suppression mission normally requires a
minimum volume of fire.
There is no MTO and no RREMS statement in:
Immediate Suppression
The suppression mission consists of the (4):
1 Observer identification
2 Warning order “suppress”
3 Target number of the planned target
4 Duration and rate of fire
What are the three elements of the Fire Support System?
Forward Observer (FO), Fire Direction Center (FDC), Firing Unit
A mil is a unit of angular measurement equal to
1/____ of a circle.
Why do artillery and mortars use mils instead of degrees?
Accuracy and the mil relation formula’s ability to easily convert angular deviation into lateral distance.
To convert degrees to mils, we multiply the number of degrees by
What is northwest in mils?
What are the three methods used to determine observer-target (OT) direction?
(1) Scaling from a map
(2) Lensatic compass
(3) Measuring from a reference point
When the FO determines the azimuth to the target (OT direction) with a compass,
the result is in mils ___. Before direction can be sent in a CFF, the FO must
apply the ___ in order to convert to mils____
magnetic, GM angle, grid
Direction should be determined to an accuracy of
10 mils
Binoculars are one of the FO’s best tools to measure angular deviation.
What are the three methods used to determine observer-target (OT) distance?
Estimation, Visibility, Map Study
Distance is expressed to the nearest
100 meters
What are the three methods of communicating target location?
(1) Polar Plot
(2) Grid Coordinates
(3) Shift from a known point
The primary disadvantage of the polar plot method of target location is that the FDC must know the FO’s ___. The FO transmits this to the FDC in the form of a __.
position / location, POSREP
With the grid method of target location, the FO locates the target to an accuracy of ___ by sending ___ digit grid.
100 meters, six
In which method(s) of target location is the FO's position not needed by the FDC?
d. A and C