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NTC Trench Live Fire

by MAJ Kurt Pinkerton and MAJ Scott Power,
Tarantula O/C Team

To improve infantry training, NTC has built two new live fire areas specifically designed to train infantry in trench, bunker and defile drills. One scenario incorporates a defensive strong point tied into the enemy's main defensive. The defense is complete with wire- and mine-protective obstacles, hardened bunkers, and trenches. A second scenario is another enemy infantry strong point consisting of a 19-bunker complex spread throughout varying terrain.

  • Units can use almost every type of weapon system available, to include mortars, AT-4s, M203s, 25-mm, TOWs, 120-mm HE and Sabot, and fragmentary hand grenades. The trenches are built to withstand the use of fragmentary grenades anywhere inside the trench and the bunkers are capable of withstanding direct fire from AT-4s and the use of fragmentary grenades inside.

  • Units can use 60-mm through 120-mm mortars to prepare the objective. The mortars can be fired at their minimum safe distances (MSDs) provided they have been properly registered or are employed in direct lay.

  • Units can use 105-mm artillery on the infantry strongpoint with trenches to prepare the objective, and they can use all forms of artillery on the bunker strongpoint complex. These objectives provide a realistic and challenging live fire for light and mechanized infantry battalions.


The "defenders" of these strong points are OPFOR infantry companies. Their task and purpose are to retain the key terrain to deny two critical avenues of approach for the heavy brigade. The enemy defends these areas using the bunkers, trenches, obstacles, observation posts (OPs) and armored vehicles to ensure they can successfully destroy any force attempting to seize the terrain.

  • The OP's mission is to over-watch primary infantry avenues of approach to provide early warning to the main defensive position.

  • The armored vehicles are used to engage any armored threat in the area, and to provide quick mobility for reinforcement as necessary.

  • The bunkers in the Refrigerator Gap defense over-watch primary armored avenues of approach with kill sacks in the restrictive terrain.

  • The trench and bunkers in the Bravo Pass defense over-watch the main defensive tactical obstacles where they tie into the terrain. There are additional bunkers, situated on dominant terrain in Bravo Pass, to protect the Southern flank of the trench from the infantry avenues of approach.


The task force has many insertion options available, to include air assault, truck, foot infiltration, insertion by Bradley Fighting Vehicles (BFVs), or a combination of all the above. Several suitable landing zones (LZs) are well within striking distance of the objective and afford the unit adequate cover and concealment for their approach. The task force must plan the insertion to be synchronized with crossing of the LD by the rest of the brigade, as the assault on the strong point is part of the larger brigade scheme of maneuver.

  • The infantry force must secure the pass before the heavy force can continue its attack to the West because of the key terrain controlled by these strong points. Normally, the light infantry forces infiltrate at night to attack at first light, which coincides with the mechanized and armored forces' crossing of the LD. Regardless of the insertion technique, indirect fires must be well coordinated while the unit is enroute to the objective.

  • Battalion and company mortars must be registered at 1,000 meters to be adjusted to fire at 500 and 300 meters from troops, respectively. Naturally, no overhead mortar fires are allowed during live fire, but there are several adequate mortar locations based on the scheme of maneuver.


About 180 days before a unit's rotation, the NTC Light Task Force Trainers (Tarantulas) provide the unit a list of training requirements for conducting these types of live-fire operations at NTC. The requirements include:

1. Units must have trained on battle drills 5, 5A, 7 and 7A.

2. Platoons must have executed the battle drills during live-fire operations at least six months prior to their arrival and in the context they plan to execute at NTC. If the battalion wants to do a night attack, they must have trained at night at Home Station.

3. The unit must have trained on the weapon systems they plan to employ, to include mortars, M2, .50-caliber machine guns, AT-4s, etc.

4. At NTC, the unit will certify all squads on battle drills 5A, 7A, and in six situations dealing with fragmentary hand grenades and AT-4s during Reception, Staging, Onward movement and Integration (RSO&I).


The methods coached by NTC Observer/Controllers (O/Cs) are a combination of doctrine from ARTEP 7-8 and 7-7J drills, as well as safety lessons learned from JRTC, NTC, and throughout the Army.

First, a review of battle drills 5A and 7A:

ARTEP Drill 5a: Knock Out a Bunker. Following the ARTEP drill, the technique recommended at NTC uses a three-man clearing team under the control of the team leader. Execute the clearing in the following manner to provide the most security to the team and the speed to keep the momentum, and develop a team system that can also be used in the trench.

  • The number one man secures the exterior of the bunker by killing enemy forces around the outside, and observes the entrance point of the bunker.

  • The number two man secures the entrance into the bunker by killing any enemy within the entrance point, and over-watches it.

  • The number three man prepares and throws the grenade into the bunker to allow the number two man to enter and kill any enemy remaining alive inside the bunker.

  • The team leader proofs the bunker and has the number one man mark the bunker by securing a VS-17 panel, with chemlights (infrared or visible), on the top of the bunker and by igniting a visual signal (star cluster or smoke).

  • The three-man team then suppresses the next bunker to allow the next element to continue to clear further bunkers.

ARTEP Drill 7a: Enter and Clear a Trench. Again, NTC recommends a three-man clearing team under the control of the team leader as the lead element in a trench. The size of the element clearing the trench is directly dependent on the size of the trench, but the size of the element pure leg of the trench should not exceed a squad and the lead element should not exceed a fire team.

  • To enter the trench, the lead element finds the point of entry (usually an area that has the least security and the best avenue of approach), and bounds forward with two riflemen immediately going foot to foot with a two-foot separation between them.

  • The team leader positions himself between, and in back of, the two riflemen.

  • The riflemen prepare their grenades and drop them into the trench under the command of the team leader. The riflemen roll away from the trench, and the team leader grabs both soldiers by the leg.

  • Once the team leader counts both grenade explosions, he orders the two soldiers to enter the trench. The soldiers roll into the trench and fire in opposite directions moving to the first corner.

  • The team leader follows immediately behind the soldiers and moves to the predetermined corner.

  • Behind the lead fire team, the remainder of the squad enters the trench, marks the point of entry, sends two more soldiers to secure one end of the trench, and prepares the other fire team to begin clearing the trench.

  • The fire team moves through a leg of the trench with the number one man killing any enemy remaining in the trench. At corners or bunkers, the number one man stops about two meters short, announces "corner or bunker" and maintains security.

  • The number two man prepares a grenade and throws it around the corner or into the bunker.

  • Once the grenade explodes, the number one man clears the corner shooting his weapon to kill any remaining enemy. If it is a bunker, the number one man enters the bunker killing any remaining enemy inside, and the number two man takes over the responsibilities of the number one man.

  • Once a corner or bunker is cleared, the number three man marks it using a VS-17 panel, with chemlights (infrared or visible), secured to the outside of the trench/bunker and a visual signal is initiated.

  • This process is continued until the entire trench and bunker complex is cleared.

Both drills sound simple, but it is often the seemingly simple things that slow us down.

Safety Techniques:

The following techniques will reduce the accidental and tactical risks in the trench-clearing element.

  • Never put more than a squad or less than a fire team in a leg. The exact size element is dependent on the size of the leg.

  • When the lead element reaches a corner or bunker, the lead fire team must have a minimum of two meters between each soldier.

  • The number one man remains at least two meters from the intersection and pulls security, and the remainder of the squad separates itself from the lead element by a minimum of five meters.

  • The number four man of the lead element is marked using a bicycle flag with chemlights, on a flex-whip antennae. By doing so, the support-by-fire (SBF) element can easily identify the lead, allowing it to provide constant suppressive fires.

  • Prepare all magazines with the last five rounds as tracers so the lead man knows when he is about to run out of ammunition.

  • Mark the entrance using entrenching tools with VS-17 panels so follow-on forces can easily identify the point of entry.

  • Echo all commands, and make the commands standard.

  • Use standard terms when using hand grenades.

    • "Prep frag" means safety pin is pulled.
    • "Frag out" means pull ring is pulled and the hand grenade is thrown around the corner or in the bunker.
    • "Drop frag" means the hand grenade is dropped in the trench at the point of entry.
    • "Grenade" means the grenade landed where it will cause harm to friendly forces.

Although you may have planned for accidental and tactical risks, things can arise when executing trench and bunker clearing drills. NTC has identified seven potential "Murphy's Laws" that could affect an operation during peacetime training and war. While at NTC, a unit planning to execute trench and bunker drills with live ammunition must show proficiency in the following reaction drills related to Murphy's Laws.

Situation 1. The unit discovers during movement that a live fragmentary grenade is missing.

a. Unit immediately halts movement and reports loss to higher headquarters and O/Cs.

b. Unit reports if pull pin or safety clip is still attached to the soldier's LBE.

c. Unit reports last known location that hand grenade was accountable.

d. Unit searches soldier's equipment and rucksack.

e. Task force secures a perimeter, issues instructions on how the route will be secured and the method of search, and elements are denied access to route along which the grenade was believed to be lost.

f. Mission does not continue until the grenade is found and a report is rendered to the senior O/C.

Situation 2. Only one hand grenade detonates when entering the trench.

a. Lead O/C notifies unit leader with lead element "not clear."

b. Team leader ensures no one enters trench at the location.

c. Team leader counts to ten. If grenade does not explode, he is informed by O/C that leg of trench is clear and no one will enter; he tactically withdraws and attempts to enter at another location.

d. Unit places soldier in the vicinity of the entry point to ensure the leg remains clear.

e. Unit attempts to re-enter in another leg of the trench.

Situation 3. Grenade does not clear a corner or entrance into a bunker when thrown.

a. The first person identifying that the grenade did not clear the corner or entrance immediately yells "grenade."

b. The lead element runs a minimum of five meters and drops to the prone. All follow-on personnel run in the opposite direction of travel to get around the previous corner.

Situation 4. A hand grenade is thrown and lands outside the trench.

a. Person identifying the hand grenade landing outside the trench yells "grenade."

b. All personnel outside the trench immediately jump into the trench.

c. All personnel in the trench lay prone inside the trench.

d. Once hand grenade explodes, responsible individual gets accountability of all personnel and ensures no one was injured.

Situation 5. Number one man is out of ammunition, has a malfunction or a misfire in the trench.

a. Individual yells "out of ammunition" (or malfunction or misfire).

b. If out of ammunition, the number one man steps to the side and the number two man takes the lead.

c. If it is a malfunction, the weapon is oriented down the trench and SPORTs is executed. If immediate action fails, the soldier orients weapon toward the ground and out, places the weapon on safe and passes on follow-on forces.

d. Weapon remains on safe with muzzle oriented toward the ground until the unit chain of command clears the malfunction. Soldier may resume trench-clearing operations once weapon is clear.

Situation 6. Misfired AT-4.

a. If an AT-4 is misfired, the soldier firing the weapon executes immediate action for a misfired AT-4. If the AT-4 still does not fire, the weapon will be put back into its carrying configuration, moved 100 meters from soldiers, and oriented away from them.

b. The area will be marked with white engineer tape and chemlights, and EOD will be called to destroy the missile.

c. If the missile was destroyed by EOD, the unit will be required to write a statement to submit to the ASP prior to departing NTC.

Situation 7. Dud missile.

a. The person who identifies that the missile was a dud immediately notifies his chain of command and the closest O/C.

b. O/Cs determine whether the dud will affect the operation.

  • If it does not, then the exercise will continue and immediately upon completion of the mission the dud will be marked and EOD will be notified to destroy the dud.

  • If the missile does affect the area, then all activities in the area will be stopped, the dud will be found and marked, and EOD will be called to destroy the dud. Once the dud is destroyed, the exercise can continue.

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