1. Identify the four methods of communication available to the observer.
2. Identify the six elements of the call-for-fire in their correct order.
3. Identify the four elements of the message to the observer.
4. Report upon firing.
3201. Means of Communication
You must maintain constant effective communication with the firing unit to receive and control supporting fires. There are four methods of communications that you may use: radio, wire, digital communications terminal (DCT), and messenger.
a. Radio. Your primary methods of communication will be by radio. You will normally request and adjust artillery fires and pass target information over the artillery conduct of fire net.
There are certain procedures that must be remembered when you are using the radio.
(1) Call signs. You will use your call sign and the FDC's call sign in your initial fire request. Once you are into your mission, you will no longer need to use call signs each time you send information. You just key the handset and give the necessary information. If the firing unit is conducting missions for more than one observer, you will need to identify yourself for each transmission. If you are conducting more than one mission at the same time, you will need to identify the mission number to which the transmission pertains.
(2) Announcing digits. Whenever you send a number or numbers to the firing unit, you must pronounce each digit of the number. For instance, if you wish to send a direction of 1490, you must say, DIRECTION, ONE-FOUR-NINER-ZERO. The only time you will not announce each digit is if the number ends in an even hundred or thousand. For instance, for 1000 you will say, DIRECTION, ONE THOUSAND not DIRECTION, ONE-ZERO-ZERO-ZERO. For 1300, you must say, DIRECTION,
Do not say REPEAT on the radio to ask someone to say TRANSMISSION AGAIN!
Say, SAY AGAIN, OVER. When you ask a station to SAY AGAIN, they will say their last radio transmission over again. When you ask the station to repeat, their next transmission will be SHOT, OVER.
(4) Read back. Every time that you make a fire mission essential transmission to the firing unit, they must read it back to you, word for word. Every time they make a fire mission essential transmission to you, you must read it back, word for word. The reason for this is to ensure there is no misunderstanding in targeting information. A mistake in target location could cost the friendly people their lives.
(5) Correction of errors. Any mistake made during a transmission must be clearly corrected so that it is understood it is a correction of an error. Suppose you sent this target location for a shift mission; the message would be
DIRECTION 1600, LEFT 500, DROP 1000, OVER.
The FDC should read back
DIRECTION 1600, LEFT 500, DROP 1000, OUT.
As they read back your transmission you realize that you meant to say right and not left. You then say
CORRECTION, RIGHT 500, OVER.
The FDC should then read back
DIRECTION 1600, RIGHT 500, DROP 1000, OUT.
This same procedure is true whether you make the error in announcing or if the FDC copies it wrong and makes the error in the read back.
b. Wire. You can use wire communications to the extent permitted by the tactical situation, time, and personnel available. In a static defensive posture, a landline may be used between the company commander and a remote observation post.
c. Digital Communications Terminal (DCT). The DCT is a handheld device that enables users to rapidly prepare, transmit, and receive both text and graphic messages (clear and encrypted)
d. Messenger. The FO may use this method of communication, tactical situation permitting.
This method is a secure method of sending fire plans. It reduces radio traffic thus hampering enemy direction finding.
3202. Call-for-Fire
The call-for-fire is a request for fire containing all data necessary for obtaining the required fire on a target. It is a concise message prepared by the observer and transmitted as a request, not as an order. It is sent quickly, but clearly enough to be understood, recorded, and read back without error by the FDC. The call-for-fire consists of six elements and is transmitted in three parts, with a break and read back after each part. The six elements of the call-for-fire are: observer
identification, warning order, target location, target description, method of engagement, and method of fire and control. These must be transmitted in the following order:
v The observer identification and the warning order are the first transmission.
v The target location is the second transmission.
v The target description, method of engagement, and the method of fire and control are the third transmission.
a. Observer identification. The observer identification lets the FDC know who is calling. Use your call sign to identify yourself. Once given, call signs are omitted from subsequent
transmissions during that mission unless there is a chance of confusion; for instance, another observer is conducting a mission at the same time you request your mission.
b. Warning order. The warning order clears the net for the fire mission and tells the FDC what type of mission you want and the method of target location. The warning order consists of the type of mission, the size of the element to fire for effect, and the method of target location.
(1) The type of mission will be one of the four types you learned about in the last lesson:
adjust fire, fire for effect, suppression, or immediate suppression.
(2) The size of the element to fire for effect is normally a battery but you may request more or less. For instance, if you have a very large target, you may want a battalion
Example: You want to call in an adjust fire mission using a battery in effect, and you have located the target by shifting from known point 2.
Your first transmission would be C30 THIS IS C56, ADJUST FIRE, SHIFT KNOWN POINT 2, OVER.
c. Target location. You must tell the FDC where the target is to receive fire on it. If you used the grid method for target location, announce the grid coordinates. For the polar method, give the direction and distance from you to the target. If you are using the shift method, give your OT direction, then how far right or left of the known point the target is (lateral shift), then how much closer or farther the target is from the known point to you (range shift). This is given as ADD or DROP from the known point in 100 meter increments. Next, you would give a vertical shift if the target is 30 meters higher or lower than the known point. Vertical shifts are given as UP or DOWN.
Example: Your target is on a direction of 3860, it is 50 mils right of known point 2 (your shift factor is 3), and you estimate the target to be 600 meters farther than known point 2. Your map shows the area where the target is to be 40 meters lower than known point 2.
Your second transmission to FDC would be DIRECTION 3860, RIGHT 150, ADD 600, DOWN 40, OVER.
d. Target description. Your description of the target should be brief and accurate. It should tell the following:
vWhat the target is (troops, trucks, supply dump, etc.)
vWhat the target is doing (digging in, in assembly area, refueling) vThe number of elements in the target (squad, platoon, three trucks) vThe degree of protection (in open, in fighting holes, with overhead cover) vTarget size and shape (linear, rectangular, circular, or irregular shaped)
(1) A linear target (a target greater than 200 meters in length but less than 200 meters in width) is described by sending the FDC an attitude and length of the target. Attitude describes the direction of the line in relation to the north/south line and is given as an
(2) A rectangular target is greater than 200 meters in length and width and is described to the FDC by length, width, and attitude. For example: 400 by 200, ATTITUDE 2800.
(3) Circular targets are targets having a radius greater than 100 meters and are described to the FDC by the radius. For example: RADIUS 300.
(4) Irregular shaped targets are described using the center of the target, the length, depth, and the attitude (if required).
e. Method of engagement. You may indicate how you want to attack the target. This element consists of the type of adjustment, trajectory, ammunition, and distribution. These sub- elements will all be standard unless you specify otherwise. Nonstandard subelements are DANGER CLOSE and MARK.
(1) The standard adjustment is area fire. If you want precision fire you must request DESTRUCTION.
(2) You announce DANGER CLOSE in the method of engagement if the rounds will impact close to friendly troops. DANGER CLOSE for mortars is 400 meters, for artillery it is 600 meters, and 750 meters for naval gun fire (5 inch).
(3) MARK is included in the method of engagement if you are going to call rounds either to orient yourself or mark targets for ground troops, aircraft, or other fire support.
(4) The standard trajectory is low angle for artillery. If you need high angle fire you must request it. Mortars only fire high angle.
(5) There are several types of ammunition available to the observer. The standard type of ammunition is HE/Q. If HE ammunition is specified in the call-for-fire, HE with fuze Q will be fired in the adjustment and fire for effect phases. The term "in effect"
indicates that the projectile/fuze specified is desired during fire for effect.
Nonstandard types of ammunition are specified in the call-for-fire. The observer must state either a projectile or a fuze. For example, "Shell ICM" (projectile) and "VT in Effect" (fuze). Shells illumination, ICM, and smoke can only be fuzed with fuze time.
Figure 3-1. Types of sheafs.
f. Method of fire and control. This element indicates the desired manner of attacking the target, whether you want to control the time of delivery of fire, and whether you can observe the target.
(1) Method of fire. In area fire, adjustment is normally conducted with one gun. If you feel you need more than one gun, you may request it. Mortars normally adjust with the center tube of the platoon or section.
(2) Method of control. Without controlling measures, the FDC will fire the howitzers when they are ready. This may cause the rounds to burst in the target area at a ragged interval. If you need rounds quickly, you will receive them fastest by not controlling them. Controlling the time to fire and causing the rounds to impact at the target simultaneously will cause the greatest shock effect on the target. You can control the timing of the firing by putting the mission at your command or by coordinating the timing.
(a) AT MY COMMAND. If you want to control the time of delivery of the fire, announce, AT MY COMMAND. When the howitzers are ready to fire, the FDC will announce, BATTERY/BATTALION IS READY (they will use the last letter of the call sign, not the word), OVER. When you are ready, say, FIRE. AT MY COMMAND will remain in effect until you announce CANCEL AT MY COMMAND.
(b) CANNOT OBSERVE. There may be times when you can't see the target because of vegetation, the terrain, the weather, smoke, or maybe incoming fire.
You can still fire the mission by announcing, CANNOT OBSERVE.
(c) TIME ON TARGET (TOT). There are times when you will want to control the time of impact of the rounds. You may do this by using a synchronized clock, elapsed time, or an event (e.g., H-Hour). A synchronized clock is established by the senior headquarters and disseminated to all maneuver and fire support units. It requires periodic time checks to ensure accuracy (e.g., TIME ON TARGET, 0815, OVER). Elapsed time is expressed in relation to the transmission of a mark (e.g., TIME ON TARGET TEN MINUTES FROM MY MARK). The term MARK is used for artillery, mortars, and naval gunfire. The term HACK is used when working with air. To give your mark say,
STANDBY FOR MARK . . . 5, 4, 3, 2, 1 MARK OVER.
The timing of fires may be in relation to an event, such as H-Hour. However, you must ensure all concerned agencies know the correct time of H-Hour (e.g., TIME ON TARGET H+5, OVER).
(d) CONTINUOUS ILLUMINATION. This is a type of fire in which the illuminating projectiles are fired at specified time intervals to provide uninterrupted lighting on the target or specified area. If no interval is given, the FDC will determine the interval by the burning time of the ammunition used. If any other interval is required, it is indicated in seconds.
(e) COORDINATED ILLUMINATION. This is a type of fire in which the firing of illuminating and high explosive projectiles is coordinated to provide illumination of the target and surrounding area for spotting and adjusting fires.
You may order the interval between illuminating and HE shells in seconds or use normal at my command procedures.
(f) CEASE LOADING. When firing two or more rounds, the command CEASE LOADING is used to stop the loading of rounds into the guns. The gun sections may fire any rounds that are already loaded.
(g) CHECK FIRING. This command is used to cause an immediate halt in firing.
(i) REPEAT. Repeat is not sent in the initial call-for-fire, it is used only in the adjustment or fire for effect phase of the mission. In adjustment it means to fire the same data as the last round. In the FFE phase, it means to fire the same number of rounds using the same method of fire for effect. Changes may be requested to number of guns, previous corrections, interval, or ammunition.
(j) FOLLOWED BY. This is a part of the term used to indicate a change in the rate of fire, in the type of ammunition, or in another order for fire for effect (e.g., WP FOLLOWED BY HE).
Example: Your target is two BRDM's with what appears to be a platoon of infantry sitting around in small groups apparently eating. You determine the standard adjustment is best, there are no friendlies near, and there is no reason for high angle fire. You want to use ICM in effect, and one round per tube is all you should need. The standard sheaf will cover the target area. You want the rounds as quickly as you can get them, so you will let the FDC control the firing.
Your third transmission to the FDC will be
TWO BRDM'S WITH DISMOUNTED INFANTRY PLATOON IN OPEN, ICM IN EFFECT, OVER.
FDC will send back
TWO BRDM'S WITH DISMOUNTED INFANTRY PLATOON IN OPEN, ICM IN EFFECT, BREAK, AUTHENTICATE LIMAFOX-TROT, OVER.
You authenticate, and your call-for-fire is complete.
3203. Message to Observer
After receiving the call-for-fire, the fire direction officer determines how the target will be attacked. That decision is announced to you in the form of a message to observer. The message to observer consists of the unit(s) to fire, any changes to the call-for-fire, number of rounds, and the target number. The FDC will provide other information, as needed, in the message to the observer.
a. Units to fire. Units to fire refers to the battery or batteries that will fire the mission. If the battalion is firing in effect with one battery adjusting, the FDC designates the fire for effect unit
b. Changes to the call-for-fire. Any changes to your requests in your call-for-fire will be announced.
c. Number of rounds. This is the number of rounds, per weapon, that will be fired in the fire for effect phase of the mission.
d. Target number. A target number is assigned by FDC to each mission to facilitate processing subsequent corrections.
e. Other information. There are times you may need additional information that is pertinent to the mission, such as
(1) Probable error in range. If the probable error in range (PE/R) is 38 meters or greater during a normal mission, or 25 meters or greater in a precision mission, the FDC will inform you in the message to observer.
(2) Angle-T. Angle-T is the angle formed at the target by the intersection of the OT line and the gun target line. When Angle-T is equal to or greater than 500 mils, the FDC should inform you in the message to observer.
(3) Time of flight. Time of flight is the time it takes the round to reach the target. The time of flight is sent on a moving target mission, when adjusting high angle fire, when firing shell HE in a coordinated illumination mission, when using BY SHELL AT MY COMMAND, or when you request the time of flight.
3204. Report Upon Firing
The firing unit will transmit SHOT after each round in adjustment and after the initial round in the fire for effect phase. You must acknowledge each.
The firing unit may also report SPLASH. This informs you that your round will detonate in 5 seconds. You may request SPLASH if the FDC doesn't send it. To request a splash, use the transmission, REQUEST SPLASH, OVER. This would allow you to remain under cover and concealment while awaiting fires. It also helps you to identify your rounds if other missions are being conducted in the same area. There is no requirement to acknowledge SPLASH.
Exercise: Complete items 1 through 4 by performing the action required. Check your responses against those listed at the end of this study unit.
1. Which of the following provides the six elements of the call-for-fire in the correct transmission order?
a. Observer identification, warning order, target location, target description, method of engagement, and method of fire and control
b. Warning order, observer identification, target location, target description, method of engagement, and method of fire and control
c. Observer identification, warning order, target description, target location, method of fire and control, and method of engagement
d. Warning order, observer identification, target description, target location, method of engagement, and method of fire and control
2. Which transmission will give you a 5 second warning to the impact of the round?
a. "SHOT, OVER"
b. "SPLASH, OUT"
c. "REQUEST SPLASH, OVER"
d. "TIME ON TARGET, OVER"
3. The four elements of the message to observer are the unit to fire, the ______________, the ________________, and the target number.
a. number of adjusting rounds, number of FFE rounds b. changes to the call-for-fire, number of rounds in effect c. number of adjusting rounds, number of guns to fire d. type of adjusting rounds, type of FFE rounds
4. You are firing two missions at the same time and are into both missions. You are the only observer on the net. Which is the correct method to use to make corrections?
a. Key the handset and announce your corrections.
b. Identify yourself and announce your corrections.
c. Identify yourself and the mission number and announce your corrections.
d. Identify the mission number and announce your corrections.
Lesson 3. SPOTTING AND CORRECTIONS