An Engagement Area Primer

3km, and finally into attack formation up to 1km from the defender.3 If the engagement area is 2800m in depth, the enemy regiment will probably be in company pre-battle formation the first time the defender could engage. In company pre-battle, the regiment is in platoon columns. If the regiment is attacking with two battalions up/one back, then there could be a maximum of 24 platoons in column. Each column is about 150m in depth with the entire frontage being about 3km (approximately 100 combat vehicles). The normal march speed is 20-25kph or 1km/3min. If the defender fires at the edge of the EA, he will be able to kill the lead vehicles but not the trail. If the defender waits one minute, the formation will travel 300m farther into the engagement area, allowing the defender to engage the entire depth of the formation.

A friendly company/team normally occupies about 1km with a separation of about 400m between teams.4 Space-wise, not more than about three teams could occupy the regimental avenue of approach. If the three teams are at 100%, then available systems could be

42. (For purposes of this example, we will assume two mechanized teams and one armor team with the second armor team as a reserve or out of position: 14 tanks, 28 BFVs). Each tank can fire approximately 6 rounds per minute and can fire 17 rounds before having to redistribute rounds into the ready rack. Each BFV can fire either TOW or 25mm; it will take approximately 8-9 seconds time-of-flight for the TOW and the 25mm can fire 300 rounds before having to reload. Historically, destroyed vehicles have had multiple tank holes in them, so those 17 rounds per tank you were counting on are halved to 8. Have you considered resupply? Now the math. In a perfect world, 42 defenders could fire and kill 42 attackers in the first volley. However, the 14 tanks would fire and 8 seconds later the TOWs would impact. If the first volley has a 90% success, that still leaves 64 combat vehicles [(42x.90) - 102 = 64] in the first echelon to return fire. Surprise is now gone. If the attacker is really terrible at gunnery and can only hit 20% of the time that means now 13 defenders are destroyed but more importantly many of the defenders are suppressed. If the remaining 29 defenders fire and kill with a 90% hit rate that leaves 38 attackers to return fire. During this time the attacker has probably moved about 500m bringing it to within 2000m of the defender. In another minute, the trail MRB will enter the engagement area and be able to engage with approximately 51 combat vehicles.

If the remaining 38 attackers fire with a 20% hit rate, they will destroy 8 defenders leaving 21.

The 21 defenders fire with 90% PK (Probability of Kill) that leaves 19 attackers; the attackers return fire with 20% PK destroying

4. Another 500m has been traveled and 51 combat vehicles from the trail MRB enter the engagement area and fire with a 20% PK, destroying 10 defenders and leaving 11 (Figure 1). The commitment of the reserve may not halt the enemy’s advance. However, if the defender is successful, it will still only have less than 30% combat power remaining. 30% is not exactly the MTP standard5 and is far below the American public’s expectation for casualties.

Battlefield calculus will help the commander visualize what assets he needs to use in order to increase his firepower and force protection. He needs to fight the regiment one small bite at a time. If the commander does not know the enemy, then he may try to build a very large EA with all four teams shooting into the EA without mutually supporting fires. The attacking regiment could then use its small attack frontage to isolate one or two teams. An MRR attacking a battalion that wasn’t using any of its available combat multipliers could easily destroy that battalion (Figure 2).

As you do the calculus, either during the Commander’s Estimate or during 34 ARMOR — Start Loss/1min Remaining after 1min Loss/2min Remaining after 2 min Blue 42 13 29 70% 7 22 52% Red 101 38 63 63% 26 37 36% Loss/3min Remaining after 3min Loss/4min Remaining after 4min Blue 3 19 44% 0 19 44% Red 20 17 17% 17 0 0% Assumptions: a. PK for Blue is 90% b. PK for Red is 20% c. Attacker continues to move unimpeded Start Loss/1min Remaining after 1min Loss/2min Remaining after 2 min Blue 58 24 34 59% 18 17 29% Red 171 52 119 69% 31 88 51% Loss/3min Remaining after 3min Blue 15 2 4% Red 15 73 43% Assumptions: a. PK for Blue is 90% b. PK for Red is 20% c. Attacker continues to move unimpeded Figure 1. Losses over time when 3 companies defend against 2 MRBs attacking abreast before commitment of reserve or the trail MRB entering the EA.

2,800m 3km 150m AAA

AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA AA AAA

AA AA AA Visualizing “Battlefield Calculus” the staff’s Course of Action development, it will also help determine when, where, and for what purpose the reserve should be committed to reinforce, counterattack, or otherwise stop a penetration.

Proper planning of obstacles, indirect fires, and smoke can disrupt the movement of the regiment, allowing the task force commander to engage only one battalion at a time. While one of the lead battalions is negotiating an obstacle, it can receive indirect fires as well as direct fire that would further increase the attacker-to-defender ratio. Position obstacles to support direct fire. Obstacles need to be emplaced after weapons systems are positioned. This may sound overly simple. However, too often, maneuver commanders tend to do two things when planning obstacles: draw them on a map and then let the engineer site in the obstacle; and either not know the intent for a particular obstacle or not convey the intent for an obstacle to his subordinates.

Obstacles do not have to kill the enemy to be successful. Many times, the only needed effect is to make the enemy change his direction of attack, or pause long enough to suffer the effects of direct or indirect fire. As the following paragraph will illustrate, your plan may require fixing an enemy unit in place long enough for combined direct and indirect fires to destroy it. The obstacle plan can disrupt the enemy formation by slowing one unit long enough to engage the other unit piecemeal.

Planning for obstacles should have four intents: fix, disrupt, block, or turn.6 Proper planning of obstacles will be critical in enhancing the direct fire fight and enhancing force protection. Siting the obstacles is a commander’s business. If the commander decides where to kill the enemy, he should site in the obstacles. The commander may have his S3 or a company commander site the obstacle but only after the task force commander has personnally walked the ground. This of course means that time management is critical to the commander in order to allow him to get to the battle positions. Plan fires to support direct fire and obstacles. Once the direct fire fight has been planned and supported with obstacles, indirect fire planning can occur to enhance the force protection, increase the firepower, and assist in the attacking force’s destruction. “Within the EA, fires should be planned to reinforce obstacles, to provide better shots for direct-fire weapon systems, and to cover dead space.”7 When you plan fires in the engagement area, don’t assume away any part of the problem. If you need to destroy an MRC, how long must you hold it in place for the destruction to take place? What does it take to destroy an MRC? Apply some more “Battlefield Calculus.” At the NTC, it would take 396 rounds to destroy the MRC. (54 rounds DPICM per tank + 18 rounds per BMP = 396rds). A DS FA battalion can fire a sustained rate of 24 rounds per minute. 396/24 = 17 minutes. What will you have to do to keep that MRC in place 17 minutes?

Make sure the intent for fires is clear. Drive the engagement area. It does not help to have a perfect plan on paper if the maneuver systems cannot “see” into the EA. Have someone drive through the engagement area — before emplacing the obstacles. This will help in positioning the direct fire systems to kill the attacker, in siting in the obstacles, and in identifying the dead space that needs covering with direct and indirect fires.

Rehearse. Rehearse. Rehearse! The last piece in synchronizing the engagement area is rehearsing the plan. There are many rehearsal techniques available, from map rehearsal to full dress rehearsal.8 Determine the best technique by the amount of time available and what the commander intends to accomplish with the rehearsal. It is important that the rehearsal is planned. Someone has to be in charge

– the executive officer/S3 or a trusted agent needs to run the show and not waste valuable time. The rehearsal is not a wargame, nor is it time to develop a course of action. If new courses of action result from a rehearsal, then the Deliberate Decision Making Process was not completed properly. Know before the rehearsal the critical tasks that need rehearsing. Establish a time limit, and stick to it. In summary, developing the engagement area requires a logical sequence in order to synchronize firepower at a decisive point on the commander’s chosen ground. The seven steps depend on the competence of the commander in visualizing the fight and deciding where to kill the enemy. In order to kill the enemy, the commander must have an in-depth knowledge of his units’ capabilities, the enemy’s doctrine and capabilities, and he must be able to see how the terrain can become a combat multiplier for the unit.

It also takes a little “Battlefield Calculus” to ensure you have plenty of firepower and fires focused into the engagement area.

Additional information on developing engagement areas is available at the Center for Army Lessons Learned, Fort Leavenworth, Kansas.