How to Plan, Rehearse and Execute a Prep by Echelonment: Combat Training

How to Plan, Rehearse and Execute a Prep by Echelonment

by MAJ Jack Pritchard and SFC Sean Harris

Scenario: Task Force (TF) 3-303 Infantry (INF) is conducting a deliberate attack to destroy an enemy command and control (C2) node. The task force commander has expressed his desire to prepare (prep1) the objective by an echelonment of fires. This will allow maneuver forces to continuously move toward the objective unhindered by direct fire from the objective. The battalion fire support officer clarifies with the commander that he wants to disrupt enemy forces on the objective until maneuver forces breach. From this, the essential fire support task (EFST) "disrupt enemy forces protecting the C2node on OBJ FOX" is identified. Task, purpose, method, and endstate are written by the Fire Support Officer (FSO) and included in the scheme of fires (fires paragraph) (see Figure 1).

SCHEME OF FIRES

Task: Disrupt enemy forces protecting the C2node on OBJ FOX.

(Note: The conditions statement would not be included in the scheme of fires. It is provided here for clarity.)

Conditions: Given mortars, field artillery (FA), naval surface fire support (NSFS), and close air support (CAS) assets for indirect fire (IDF) support. A pinpointed objective; risk estimate distances (REDs) from the commander; planning guidance from the commander; three FISTs; a direct support FA BATTALION (BN) FDC; communications with a naval ship, a tactical air control party (TACP); and a rate of movement (meters per minute) from the assault (or breach) element.

Purpose: Assist in the destruction of enemy forces on OBJ FOX; allow TM B to continuously move to the breach site unhindered and obscured by direct fire from the objective.

Method: Prep OBJ FOX by echelonment of fires. Initially mass NSFS (5" 54), FA (155s, 105s), mortars (81s, 60s) onto the OBJ FOX for 2 minutes, when lead elements of TM B cross PL DODGE. At H-24 (or when lead elements are 600m from the outside ring of the objective), suppress the objective with FA fire for 16 minutes. At H-16 (400m) suppress with mortar fires for 10 minutes. When TM B is within 150m of the objective, 105mm HC smoke will obscure enemy forces (for 7 minutes) until the support by fire (SBF) force has occupied SBF position X-RAY and TM B is breaching. FA and mortar fires will overlay ensuring the objective is continuously suppressed. See method sketch Figure 4 for more information.

Endstate: Destroy enemy forces on OBJ FOX.

Figure 1

Battalion FSOs have difficulty accomplishing the above task. Often FSOs attempt to accomplish this task for the first time during a field training exercise deliberate attack. Fire support manuals offer little help in the form of steps or instructions. Risk estimate distances for mortars, field artillery, and naval surface fire support (NSFS) assets are not readily available and are not published in fire support manuals. (Minimum Safe Distance [MSDs] are used for peacetime combined arms live fire exercises.) The intent of this article is to provide a technique and example for the echelonment of a preparation which allows maneuver forces to continuously move to an objective while enemy forces on the objective are suppressed.

After receiving guidance from the task force commander concerning his desire to prep the objective by echelonment of fires, the FSO proceeds with the staff into course-of-action (COA) development. Not every attack warrants a prep. FSOs should consider several factors prior to planning a preparation (see Figure 2); however, the final decision always rests with the maneuver commander. With this guidance the FSO ensures that all COAs being developed include a preparation by echelonment. When the staff begins to war-game each COA, the FSO ensures the preparation is discussed in detail. The FSO must be prepared to recommend which COA he feels best supports a preparation by echelonment during COA analysis and comparison.

CONSIDERATIONS FOR PREPARATION FIRES

Will the loss of surprise from the preparation be offset by the damage done to the enemy?
Are there enough targets and means to warrant a preparation?
Can the enemy recover before the preparation fires can be exploited?

FM 6-20-1, p. 5-4

Figure 2

Once a COA has been selected, the FSO has several things to do to ensure the EFST is executed:

NINE (9) - STEPS FOR ECHELONING A PREP

STEP 1 - Determine what indirect fire support assets are available for the preparation.

Consider consolidating company (60mm) mortars.
Contact the BDE FSE to determine how many volleys of FA lethal munitions have been allocated and how much HC smoke is available to support the task force.
Determine how much mortar ammunition is available.
Determine where the indirect fire assets will be positioned when the preparation is fired.
Determine if naval surface fire support is available for the preparation.
Determine if the naval gun target (GT) line supports2using NSFS as a part of the preparation.
Determine if the commander wants to employ CAS as a part of the preparation. If he does, ensure the Joint Tactical Air Request Form3is submitted in enough time for the air tasking order (ATO) cycle.

Ultimately, the FSO wants to know--how many indirect fire weapons can be initially massed onto the objective, and how much lethal and nonlethal ammunition is available for the preparation?

STEP 2 - Meet with the commander to verify risk estimate distances (see Figure 3) and attack criteria. Risk estimate distances allow commanders to estimate the risk in terms of the percentage of friendly casualties that may result from the employment of indirect fires with close proximity of friendly forces.4

Risk estimate distances are established in combat and are represented in peacetime by a similar terminology called minimum safe distances used during fire exercises. Risk estimate distances (REDs) are based on the range the weapon will be firing from and amount of risk (10 percent PI or 0.1 percent PI) the maneuver commander is willing to accept. "Note that friendly forces outside the 0.1 percent PI [probability of incapacitation] distance and MSD [or risk estimate distance] may still be subject to weapons fragments. Commanders and fire supporters must carefully weigh the choice of ordnance and the accuracy5and proficiency of the firing unit in relation to the risk of fratricide."6In most cases, the 0.1 percent PI (one-in-one-thousand probability of incapacitation) distances will be sufficient. Although the FSO will make recommendations, ultimately the commander must make the decision for each weapon being employed. The FSO records these distances, and uses them during the technical planning of the preparation. Once the REDs have been decided upon, the FSO must confirm with the commander what he anticipates the results of the preparation will be. Based on the availability of ammunition, the FSO and commander must agree upon the attack criteria. Attack criteria should be detailed and specific (neutralize OBJ Fox is too vague). Indirect fires may destroy one target on the objective while neutralizing the remaining targets. If a breach is expected, the FSO should confirm with the commander if he wants to use smoke (see Figure 6) and/or illumination on the objective. If the commander is not satisfied with the effects that can reasonably be achieved by the assets provided, he may need to adjust his ammunition allocation from brigade.

STEP 3 - Begin with planning targets on the objective. From the situation template and known enemy locations, begin selecting the targets that will be fired during the preparation. One technique suggests FSOs assign target numbers in increments of 5s (2000, 2005, etc.). This allows the FSO to refine the target's location systematically. As the S2 receives information from the reconnaissance, he then provides this update to the FSO who changes the target's target number by one. Thus 2000 becomes 2001. Never change the grid without changing the target number. Weapons and ammunition should be matched to the appropriate target (i.e., 155mm HE/delay or 105mm HC smoke).

STEP 4 - Find out what the lead element anticipates their rate of movement to be based on the situation, conditions, and the force assigned. Normally, this is the assault or breach force. The FSO should ask the element commander what he anticipates the rate of movement in meters per minute will be. A movement speed of 1.2 kilometer per hour equates to approximately 20 meters per minute. Two kilometers per hour equates to about 33 meters per minute. The rate of movement becomes critical during the last kilometer to the objective. Precision Location [Global Positioning System] Receivers (PLGRs) can provide movement speeds in meters per minute.

The FO moving with the lead element must be able to track the movement speed, and confirm for the FSO that the unit is moving at the correct speed. The S2's intelligence preparation of the battlefield (IPB) should assist the commander in determining a reasonable rate of movement. (Note: The FSO may need to alter the plan during execution based on unforeseen difficulties in movement rates. The bottom line is twofold: the FSO must remain flexible and have a system of tracking the movement of the lead element.)

STEP 5 - Develop the Schedule of Fires (here is one method for this task). Essentially there are three phases to the method: massing fires on the objective, suppressing the objective and obscuring the objective. The FSO may find it helpful to sketch out the plan. Massing fires is a relative term that can be developed using METT-T. (See Figure 4 at the end of this article.)

Draw the risk estimate distance lines for each asset.
Associate H minus times with each line based on the rate of movement.
Plot the targets on and around the objective.
List the assets available along the left side of the sketch.

Massing Fires on Objective

Decide what target each asset will engage during the initial massing of fires onto the objective and how many rounds each asset will fire based on the desired effects for each target.
Decide when fires will be massed on the objective. After considering all assets available to mass fires on the objective, the FSO determined that NSFS would take the longest time to fire (see Figure 5). In this example, the FSO determined it would take NSFS 2 minutes to fire 80 rounds; therefore, rounds will begin landing on the objective when lead elements of the task force reach PL DODGE 650 meters from the objective and will cease when the lead elements reach the RED line of 600m (H-24) for the 5"/54. This is based on a rate of movement of 25 meters per minute (mpm); a rate of movement of 35 mpm would cause fires to begin 670m from the objective.
Label the sketch (see Figure 4 at the end of this article).

TIME REQUIRED TO DELIVER THE MASSED FIRES
SYSTEM	NO. OF GUNS/TUBES	NO. OF ROUNDS FIRED	MAXIMUM1RATE OF FIRE	TIME REQUIRED TO FIRE
5"/54	2	80	202	2 minutes
155mm	4	12	4	45 seconds
105mm	12	48	10	24 seconds
81mm	4	40	35	17 seconds
60mm	4	40	30	20 seconds
1 Reference FM 6-20-20. 2Number of rounds per gun or tube per minute.

Figure 5

Suppressive Fires

Decide what target each asset will engage during the suppressive fires phase of the echelonment of fires.
Determine how many minutes each asset can provide suppressive fires based on the REDs. Using the RED of 600m for NSFS and 350m for 155s (Note: The commander and FSO agreed upon a RED of 350m for 155s. Based on the maximum range of 450m and 2/3d range of 280m [see Figure 3]), the 155s are able to provide 10 minutes (600m - 350m = 250m ÷ 25 meters per minute = 10 minutes) of suppressive fires before the lead elements of the task force reach the RED for 155mm howitzers (350m from OBJ FOX). Use this same analysis for all assets.
Plan for redundancy of assets to ensure the objective is continuously suppressed.
Decide how many rounds each asset will fire during this phase of the preparation.
Label the sketch (see Figure 4).

Obscuration Fires

Based on the guidance the FSO receives from the commander, "smoke [HC] may be used to continue to suppress the enemy by obscuring his view of the battlefield when the lethal fires cease"7(see Figure 6). When scheduling smoke, back off 1 minute to allow for buildup time if using HC smoke only and not white phosphorus (WP) for the initial rounds.8In this example, the 105mm howitzers will begin firing (HC smoke) 1 minute before the 60mm mortars cease firing (see Figure 4).

OBSCURATION FIRES

Slow enemy vehicles to blackout speeds.
Obscure the vision of direct fire gunners.
Reduce the accuracy of enemy-observed fires by obscuring COPs.
Cause confusion and apprehension among enemy soldiers.
Limit the effectiveness of the enemy's visual C2signals.
FM 6-20-1, p. F-2

Figure 6

Additional Considerations

Ensure firing assets are available for targets of opportunity.9In this example, only two of the four 81mm mortars are shooting during the suppressive fires phase. The same is true for the two sections of company mortars (collocated). Normally, field artillery assets must be available for counterfire missions.
Determine if the commander wants to shift fires onto targets away from the breach site. (Another technique suggests the FO with the support by fire element engages targets of opportunity.)
If additional obscuration is needed for the breach, determine who calls for, adjusts it, and what asset provides the fires.

STEP 6 - Decide how the massing of fires phase of the preparation will be initiated. An at-my-command status could be used; however, multiple times of flight from different assets make this difficult. A better technique uses an H-hour schedule. Each asset's fire direction center determines when it needs to fire based on the schedule of fires. In this example, all assets have rounds impacting at H-26 (PL DODGE). This technique requires the establishment of a time hack:

The FO moving with the lead platoon works with the BN FSO to establish the time hack. This FO must be experienced and have a thorough understanding of how a schedule of fires works. The CO FSO and BN FSNCO monitor and serve as alternates.
The FO reports movement times and locations to the BN FSO on the BN fire support coordination net.
A phase line 250m from PL DODGE is established--PL FORD. This phase line is used to establish the time hack. The 250m equates to 10 minutes from PL DODGE; therefore, when the FO calls PL FORD, the lead elements are at H-36 (900m from OBJ FOX). Whenever possible, the FSO places the phase line on a terrain feature to verify and back up the GPS.
When the FO approaches PL FORD, he verifies communication with the BN FSO and counts down to a H-36 hack. This hack is critical, and the FO must mark the time on his watch.

Once the H-36 hack is verified, the BN FSO gets all firing assets on the H-hour schedule. The company FSO monitors the hack and verifies all data the FO is sending to the BN FSO. The company FSO must ensure the lead platoon leader completely understands the H-hour schedule. Both the platoon leader and FO must understand the importance of verifying the rate of movement with the REDs and the H-minus times. For example, at H-31 the platoon can be no closer than 775m to wire around the objective. If the platoon is closer, it will have to slow down; in this example, it can be no closer than 600m until H-24 minutes. Risk estimate distances should be based on the outer ring (often the wire) of the objective. This allows any target on the objective to be engaged by any asset.

The company FSO and his FOs input the breach location in their PLGRs as a way point. In addition to this, the FO (and FSO) must continuously compare their locations to the RED lines on their maps. The RED lines must be drawn to scale. (Note: The BN FSE can greatly assist by tracking the platoon's location and comparing it to the REDs and H minus times.) Finally, the BN FSO must be prepared to direct the mortars to fire for additional minutes in the event that the task force is delayed. If the FSO alters the mortar suppressive firing times, he may have to delay the firing of smoke.

STEP 7 - Brief the Plan.

Backbrief the CDR and S3 prior to completing the scheduling work sheets.
During the fire support portion of the operation order brief, use the sketch and be thorough. It is critical that the company commanders understand the prep prior to developing their plans.
Rehearse the briefing.

STEP 8 - Complete the Scheduling Work Sheets:

Reference FM 6-20-50, Appendix F.
Maintain copies of all worksheets.
Ensure all assets receive a copy.
Provide a copy to the HHQ fire support element.

Digital fire planning devices can greatly assist FSOs in scheduling preparations.

STEP 9 - Rehearse and refine the plan. The FSO should ensure all essential fire support tasks (EFSTs) are rehearsed. This article focuses on this EFST--"Disrupt enemy forces protecting the C2node on OBJ FOX."

Ensure the echelonment of fires is rehearsed in detail during the task force rehearsal.
The battalion FSO or FSNCO attends the lead company's rehearsal to ensure the company completely understands the echelonment of fires.
Conduct a separate fire support rehearsal:
- Attendees include: S2 rep, S3 rep, company FSOs, lead platoon leader and FO, DS FA BN FDC rep, TACP, SALT, BN mortar platoon leader and FDC rep, and both mortar section sergeants.
- The FSO should rehearse the rehearsal.
- Begin with the FO establishing the initial time hack with the BN FSO.
- Rehearse all phases of the preparation separately.
- Have each player confirm H minus/plus times, REDs, rates of movement, target numbers and locations, number and type of rounds, shift times, number of minutes of suppressive fires provided by each asset, number of minutes of smoke, call signs, frequencies and graphics.
- Rehearse possible changes to the plan or contingencies (i.e., the task force is delayed and requires more suppressive fires).
- Rehearse how targets of opportunity will be engaged.
Ensure every effort is made to refine the targets being shot during the preparation. Digital fir-planning devices should greatly assist in refining the target location as new intelligence becomes available. The need to accurately locate every target being shot during the preparation cannot be overemphasized.

CONCLUSION

Nine steps for planning a preparation by echelonment have been presented. Although every situation may be different, the steps will remain the same. Using these steps as a guide, FSOs can plan and execute a prep which provides timely and accurate fires that best supports the maneuver forces.

NINE STEPS FOR ECHELONING A PREP

1. Determine what assets and how much ammunition are available.

2. Verify risk estimate distances and attack criteria with the commander.

3. Plan targets.

4. Determine what the rate of movement will be.

5. Develop the schedule of fires (the method for this task).

6. Decide how the preparation schedule will be initiated.

7. Brief the plan/confirm the method with the commander.

8. Complete the scheduling worksheets.

9. Rehearse and refine the plan.

In conclusion, two key points need to be applied to this process.

POINT 1 - The FSOs and their commanders cannot ignore the importance of ensuring accurate target (objective) location. Start early and be aggressive with the reconnaissance effort, ensuring that the FSO is "in the loop" for all reconnaissance and intelligence reporting. The use of daily targeting meetings to refine targets and focus the collection effort will assist in ensuring the accuracy required for close supporting fires.

POINT 2 - This technique for echeloning fires requires that the commander and FSO have a close working relationship. The FSO must understand the commander's intent and translate it into an effective scheme of fires. The FSO must be able to use all the tools available to him, ensuring he makes sound and timely recommendations to the commander. Finally, the plan must be flexible and adaptable to the constantly changing situation.

__________________

Notes:

1. Preparation fire is fire delivered on targets preparatory to an assault. FM 6-20-1, p. F-2.
2. The dispersion pattern of NSFS described as a narrow, elongated pattern as seen along the GT line makes this a consideration. See FM 6-30, p. 8-13, for more information.
3. DD Form 1972 (15 Nov 94). See Joint TTPs for Close Air Support, Joint Publication 3-09.3, for more information.
4. Joint TTPs for Close Air Support, Joint Pub 3-09.3, 1 December 1995, p. G-1.
5. This refers to the firing element's ability to meet the five requirements for accurate and predicted fires. See FM 6-40, p. 1-3, for more information.
6. Risk Estimate Distances for Indirect Fires in Combat, Field Artillery Journal, March-April 1997.
7. FM 6-20-1, p. F-2.
8. See FM 6-20-1, Appendix F, for more information.
9. FM 6-20-1, p. F-3.

The Field Sanitation Team

Replace Battle Drill 6

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How to Plan, Rehearse and Execute a Prep by Echelonment