There are three types of gunnery techniquesprecision, degraded, and battlesight.
• Precision gunnery is defined as: using the full capability of the fire control system to engage targets.
• Degraded-mode gunnery techniques are used when the crew cannot use the full capability of the fire control system.
• Battlesight gunnery is used when an accurate tank-to-target range cannot be determined, when the computer is inoperative, or in most surprise situations.
PRECISION GUNNERY
Precision gunnery is the most accurate technique of direct-fire engagement and is used when the tank has a fully operational fire control system. The preferred method is to use the thermal channels as the primary sight (day or night). The TIS and CITV are very effective for target acquisition, sensing, firing through obscurants, and minimizing the effects of directed-energy weapons such as laser washout. In some instances (such as desert environment), the GPS daylight channel may work better.
Normally, when using precision gunnery techniques, only four (alert, ammunition or weapon, description, and execution) of the six elements will be needed in the fire command ("GUNNERSABOTTANK FIRE"). The direction is normally omitted if the TC lays the gun for direction (for safety purposes, when using the designate function on the M1A2, the TC will announce "DESIGNATING".). The range is determined by the LRF and evaluated by the gunner and TC prior to firing.
Examples of the crew duties associated with the employment of precision-mode gunnery techniques are located on pages 8-9 through 8-12.
Note. (M1A2 SEP) When engaging targets in higher magnifications (25X or 50X), the gunner and TC must realize that the tank cannon is no more accurate than when using 13X. The target only appears closer.
Gunners and TCs must be more conscious of their final lay before squeezing the trigger. Also, if moving over rough terrain, keeping the target within the field of view may be more of a challenge. If the target is lost, go to a lower magnification to reacquire.
GUNNERY TECHNIQUES FOR MPAT
MPAT gunnery techniques, although part of precision gunnery, may require certain aim-off techniques.
Engagement Techniques
Gunnery techniques for engaging either ground targets or helicopter targets in the open with MPAT is the same as for any other main gun round. Gunners place the AMMUNITION SELECT switch to MPAT, lay on
the visible center-of-mass, lase and, when given the command by the TC, fire. The loader either checks that the AIR/GROUND switch is on GROUND (ground mode) or moves the switch to AIR and announces "AIR" (air mode) before chambering the round and announcing "UP."
In AIR mode, after the proximity fuze is fully enabled, the round will function on almost any object it detects, whether it is a target or not. Therefore, in a cluttered environment, it may be necessary to use an alternate aiming point to help make sure the round does not explode before it is in the vicinity of the target. For example, if the target helicopter is hovering or flying close to a group of trees, the round may function on the near edge of the tree line; if the target helicopter is using the top or side of a building for cover, the round may function on the building. In either case, using an alternate aiming point increases the standoff between the clutter and the trajectory of the round (whether in deflection [2-1/2 mils] or elevation [2 mils]) and, therefore, increases the chance of the round functioning on the desired target. Figure 8-6 displays a deflection offset, and Figure 8-7 displays an elevation offset.
Figure 8-6. Deflection Offset.
Sensing
In AIR mode, a black cloud of smoke is produced when the round functions on a target. This smoke allows the firing tank or wingman to sense MPAT rounds employed against helicopters.
DEGRADED-MODE GUNNERY
Sometimes it may be necessary to fight with less than a fully operational system (use degraded-mode gunnery procedures). (See Chapter 11, Survivability and Fight-Back Capability, for procedures that will allow crews to continue to fight after the tank is hit by direct or indirect fire.)
The TC may decide to fire degraded mode before the engagement starts (battlesight or fire control malfunction) or when a malfunction of the fire control system or an environmental condition during a precision engagement requires a change in the engagement. When a precision engagement has started, but due to fire control malfunction, cannot be completed, the TC may have to issue further instructions to the gunner; this depends on the urgency of the engagement and the time available. The situation may require completing the engagement using the GAS.
The degraded-mode technique used will depend on which fire control component is inoperative. The following situations may occur during an engagement. The corrective actions, including the appropriate fire command, are indicated. These actions allow the tank crew to engage targets effectively until repairs return the tank to a fully operational status, or until environmental conditions change.
LRF INEFFECTIVE
Effective use of the LRF may be lost due to any of the following:
• Internal LRF or vehicle malfunction.
• Environmental conditions (fog, falling snow, or heavy rain).
• Man-made or battlefield smoke and obscurants.
• Multiple returns from a target smaller than the LRF beam width, with interference both in front of, and behind, the target.
Note. Battlesight gunnery is the quickest method that can be used when the LRF is ineffective. It is the preferred method when targets are within battlesight range. If the situation allows, the gunner should use the stadia reticle in the GAS to determine a range to the target. On an M1A2, the TC and gunner can use stadia reticles to determine range.
Manually Indexing Range
When the gunner cannot determine range effectively using the LRF, the TC or gunner can enter the estimated range into the system manually. This allows the gunner to use the GPS and a full ballistic solution for the estimated range.
(M1 and M1A1.) If the TC enters the range, he will not announce the range in the fire command. Instead, after the gunner announces "IDENTIFIED," the TC will press the MANUAL RANGE BATTLE SGT button on the TC's panel; then, he will use the ADD/DROP toggle switch to enter the estimated range while viewing the range readout in his GPSE. The range readout will change in 10-meter increments at 50 meters per second for the first four seconds, then in 100-meter increments at 500 meters per second. Once the correct range is displayed and the loader announces "UP," the TC will give the command of execution.
If firing at a stationary target, the gunner should dump the palm switches to dump lead solution. If firing at a moving target, the TC must press the BATTLE SGT push button (after the gunner establishes a smooth track) to induce a lead solution, then use the ADD/DROP toggle switch to enter the estimated range.
(M1A2.) If the TC enters the range, he will not announce the range in the fire command. Instead, after the gunner announces "IDENTIFIED," the TC will press the MANUAL RANGE BATTLESIGHT push button on
the CID; then, he will use the four-way switch to enter the estimated range while viewing the range readout in his GPSE and CITV. For small adjustments, move the four-way switch up to add range or down to drop range at a speed of 10 meters per second. For large adjustments, hold the four-way switch up or down for four to eight seconds to add or drop range at a speed of 50 meters per second. If the four-way switch is held up or down more than eight seconds the range will add or drop at a speed of 100 meters per second. Once the correct range is displayed and the loader announces "UP," the TC will give the execution command. If firing at a moving target, the TC must press the BATTLESIGHT push button (after the gunner establishes a smooth track) to induce a lead solution, then use the four-way switch to enter the estimated range.
Note. The TC must press the BATTLESIGHT push button twice; otherwise, the CID will remain in the BATTLESIGHT mode.
If the TC wants the gunner to enter the range manually, he will announce "INDEX" and the estimated range in the fire command.
• (M1 and M1A1): The gunner will open the CCP door, turn the CCP on, press the RANGE push button, enter the range, press the palm switch, and press the ENTER push button.
• (M1A2): The gunner will go to the GCDP and press the ADJUST push button on the main menu, then press the RANGE push button on the ADJUST menu, enter the range, press the palm switch, and press the ENT push button on the GCDP keypad.
Example fire command: “GUNNER—SABOT—TANK—INDEX ONE SIX HUNDRED—FIRE.”
Note. The gunner uses the GPS, opens the CCP for M1 and M1A1 or GCDP for M1A2 and M1A2 SEP, and indexes the range announced in the fire command.
To induce and maintain lead, the gunner must keep the palm switch on the GPCH pressed. If the gunner dumps his lead, the TC can press the BATTLESIGHT push button after the gunner has established a steady track to induce the lead again.
• (M1 and M1A1): The range will change to the preindexed battlesight range. If the range to the target is different, the TC must press the ADD/DROP toggle switch to correct the range before giving the execution command.
• (M1A2): The range will change to the preindexed battlesight range. If the range to the target is different, the TC must press the MANUAL RANGE BATTLESIGHT push button on the CID, then use the four-way switch to enter the estimated range before giving the execution command.
Note. Announcing "INDEX," and having the gunner manually index the range is the least preferred method of applying a range—it is time-consuming and requires the gunner to take his eye from the sight.
Manually Applying Range Using the GAS
If the GPS is inoperative or the TC elects to fire from the GAS, he can still conduct an engagement by having the gunner determine the range using the stadia reticle or announcing the range in the fire command.
The gunner will lay the appropriate range line on the target center of mass (or offset if lead or cant must be applied), and fire when directed. Example:
Example fire command: “GUNNER—SABOT—TANK—ONE SIX HUNDRED—FIRE.”
Note. The gunner automatically shifts to the GAS and uses the appropriate reticle line.
Manually Applying Range Using the CITV Stadia Reticle
To determine the range to a full-height target, move the range/stadia reticle switch forward or backward until the outer-most index lines rest on the top and bottom of the target. The approximate range is displayed on the CITV display.
To determine the range to a hull-down target, move the range/stadia reticle switch forward or backward until the inner-most index lines rest on the top and bottom of the target. The approximate range is displayed on the CITV display.
Example fire command: “GUNNER—SABOT—TANK—CHOKED ONE SIX HUNDRED—FIRE.”
Notes. This method is used when the TC uses the CITV stadia reticle to estimate the range to the target.
The TC may also elect to have the gunner use the GAS stadia reticle to confirm the range to the target.
Loss of Symbology. Although loss of symbology due to failure in the image control unit or electronics unit does not affect the function of the LRF, it does prevent the gunner or TC from evaluating range returns. The accuracy of the LRF and the ability to select first or last return logic should provide enough confidence to fire, although range may not be displayed. If the crew is uncertain and time permits, the TC may have the gunner check the range using the RANGE push button on the CCP or the GCDP.
Computer Lockup. Damage to the CEU (TEU or HEU on the M1A2) may occur as a result of the impact of enemy direct fire. If this occurs, the gunner should move to the GAS immediately.
A computer lockup prevents ballistic solutions from being induced; the electrical triggers may also malfunction. If computer lockup is suspected and immediate return fire is required, the gunner uses the GAS and the manual firing device. At the first opportunity, move the tank to a position where the crew can troubleshoot the system. Replace damaged components as soon as possible.
CANT SENSOR FAILURE (M1 AND M1A1)
If a cant sensor failure occurs during a computer self-test, a numeral 2 will appear on the CCP display window and the CANT push button will flash. To cancel this input, the gunner should press the CANT push button, then the 0 and ENTER push buttons on the CCP keypad (the CANT push button will remain illuminated).
When the turret cants to the right or left, the gun trunnions are not horizontal. This creates a deflection and range error, causing rounds to impact low and toward the downside of the cant. As the degree of cant increases, the strike point of the round moves farther from the aiming point in the direction of the cant. Corrections for cant cannot be made while firing on the move. When engaging a target during a cant sensor failure, the crew uses the following techniques to compensate for cant:
• The gunner presses the CANT push button on the CCP to cancel the input, then presses the 0 and ENTER push buttons on the CCP keypad (the CANT push button will remain illuminated).
• The gunner lays the gun on target and lases.
• The driver attempts to locate a level firing position. (If not able to locate a level firing position, the gunner does not apply any AZ or EL corrections for KE rounds. For HEAT rounds, the gunner aims one-half target form in the opposite direction of cant in AZ, but makes no EL correction.)
CANT SENSOR FAILURE (M1A2)
If a cant sensor failure occurs during a computer self-test, a fault message will appear in Cautions/Warnings on the GCDP. To cancel this message, the gunner should press the SENSORS push button on the main menu, the ATTD push button on the SENSORS menu, the CANT push button on the ATTD menu, the MANUAL push button on the CANT menu, and the 0 and ENT push buttons on the GCDP keypad.
When the turret cants to the right or left, the gun trunnions are not horizontal. This creates a deflection and range error, causing rounds to impact low and toward the downside of the cant. As the degree of cant increases, the strike point of the round moves farther from the aiming point in the direction of the cant. Corrections for
cant cannot be made while firing on the move. When engaging a target during a cant sensor failure, the crew uses the following techniques to compensate for cant:
• The gunner presses the SENSORS push button on the main menu, the ATTD push button on the SENSORS menu, the CANT push button on the ATTD menu, the MANUAL push button on the CANT menu, and the 0 and ENT push buttons on the GCDP keypad.
• The gunner lays the gun on target and lases.
• The driver attempts to locate a level firing position. (If not able to locate a level firing position, the gunner does not apply any AZ or EL corrections for KE rounds. For HEAT rounds, the gunner aims one-half target form in the opposite direction of cant in AZ, but makes no EL correction.)
CROSSWIND SENSOR FAILURE (M1 AND M1A1)
If a crosswind sensor failure occurs during a computer self-test, a numeral 3 will appear on the CCP display window, and the CROSSWIND push button will flash. To cancel this input, the gunner should press the CROSSWIND push button on the CCP, then press the 0 and ENTER push buttons on the CCP keypad (the CROSSWIND push button will remain illuminated). The TC should not try to estimate wind speed.
CROSSWIND SENSOR FAILURE (M1A2)
If a crosswind sensor failure occurs during a fire control system test, a fault message will appear in Cautions/Warnings on the GCDP. To cancel this message, the gunner should press the METRL DATA push button on the main menu, then the CROSSWIND and MANUAL push buttons, and the 0 and ENT push buttons on the GCDP keypad. The TC should not try to estimate wind speed.
GPS AZIMUTH DRIVE SYSTEM FAILURE (M1 AND M1A1)
If the GPS azimuth drive system fails during a computer self-test, the numeral 4 will appear in the CCP display window, and the LEAD push button will flash. To cancel this input, the gunner should press the LEAD push button, then the 0 and ENTER push buttons on the CCP keypad (the LEAD push button will remain illuminated). The gunner will know that lead is not automatically induced by the computer because the reticle does not move toward the side of the GPS field of view when following a moving target or slewing from target to target. To engage a target under these conditions, the gunner must remember the following:
• A GPS azimuth drive system failure does not affect firing at stationary targets from a stationary tank.
• Since lead is not automatically applied, the gunner must apply lead using the lead lines on the reticles.
• When engaging a moving target or firing from a moving tank, the gunner must apply lead from the target center of visible mass in the direction the target is moving.
• The amount of lead is based on the type of round fired, the tracking rate of the turret, and the range to the target. The speed of a distant target is hard to estimate. The standard lead is 2½ mils for sabot or MPAT, and 5 mils for HEAT. (The recommended standard leads are based on a standard target size and speed, and may be revised.)
LEAD SYSTEM FAILURE (M1A2)
A lead system failure is indicated by an FCEU fault message displayed in the GCDP. The gunner will not notice whether lead is or is not automatically induced because the DAHA in the GPS is keeping the reticle in the center of the sight. The gunner can detect lead failure by observing lack-of-sight movement (not reticle) and turret effects with a full ballistic solution while tracking a moving target or slewing from target to target. If the gunner finds a lead system failure, he should press the SENSORS push button on the main menu, the ATTD push button on the SENSORS menu, the LEAD push button on the ATTD menu, the MANUAL push button on the LEAD menu, and the 0 and ENT push buttons on the GCDP keypad. To engage a target under these
• The amount of lead is based on the type of round fired, the tracking rate of the turret, and the range to the
• The amount of lead is based on the type of round fired, the tracking rate of the turret, and the range to the