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This chapter describes additional tasks the tank platoon may have to conduct to complement or support its primary operations of move, attack, and defend. The platoon executes these additional tasks separately or as part of a larger force.


SECTION I. Tactical Road March
SECTION II. Assembly Areas
SECTION IV. Convoy Escort
SECTION V. Passage of Lines
SECTION VI. Breaching Operations
SECTION VII. Follow and Support
SECTION VIII. Perimeter Defense
SECTION XI. Relief in Place
SECTION XII. Withdrawal

Tank platoons conduct tactical road marches to move long distances and position themselves for future operations. The main purpose of the road march is to relocate rapidly, not to gain contact. It is conducted using fixed speeds and timed intervals. Road marches are planned at the battalion and company levels. They are, however, executed by platoons.

The success of a road march depends on thorough preparation and sound SOPs. Platoon preparations should address movement to the SP, speed control, formations, intervals, weapons orientation, actions at scheduled halts, and actions at the RP. SOPs should cover actions at unscheduled halts, actions in case a vehicle becomes lost, actions if a vehicle becomes disabled, and actions on contact.

A road march is composed of three elements: the quartering party (or advance party), the main body, and the trail party. The tank platoon normally travels as a unit in the main body. Before the march begins, the platoon may provide individual soldiers or a vehicle and crew to assist with quartering party activities (see Section II of this chapter).

March Columns

There are three primary road march techniques. The commander bases his decision on the formation to be used during the march on which technique is employed. The road march is usually executed in column or staggered column formation.

Open Column

The open column technique is normally used for daylight marches. It can be used at night with blackout lights or thermal vision equipment. The distance between vehicles varies, normally from 50 meters to 200 meters depending on light and weather conditions.

Close Column

The close column technique is normally used for marches conducted during periods of limited visibility. The distance between vehicles is based on the ability to see the vehicle ahead; it is normally less than 50 meters.


The infiltration technique involves the movement of small groups of personnel or vehicles at irregular intervals. It is used when sufficient time andsuitable routes are available and when maximum security, deception, and dispersion are desired. It provides the best possible passive defense against enemy observation and detection. (NOTE: Infiltration is most commonly used by dismounted elements.)

Control measures

The following control measures assist the platoon leader in controlling his platoon during the conduct of a road march.

Map with Overlay

As a minimum, the overlay must show the SP, the RP, and the route. The SP location represents the beginning of the road march route. It should be located on easily recognizable terrain. It is far enough away from the unit's initial position to allow the platoon to organize into the march formation at the appropriate speed and interval. If time is available, the platoon leader should determine the time-distance factor to the SP. This will help the platoon to arrive at the SP at the time designated in the commander's OPORD. The RP location is at the end of the route of march. It also is located on easily recognizable terrain. Elements do not halt at the RP. They continue to their respective positions with assistance from guides, waypoints, and graphic control measures. The route is the path of travel connecting the start and release points.

Digital Overlays

Digital overlays serve as a backup to maps with overlays. They display waypoints and information concerning unit locations along the route of march that can assist TCs in navigation and help them in maintaining situational awareness.

Critical Points

These are locations along the route of march where interference with movement might occur or where timing is critical. They are represented using checkpoints. The SP, RP, and all checkpoints are considered critical points.

Strip Maps

A strip map can be used to assist in navigation. It must include the SP, RP, and checkpoints and must list the distances between these points. Detailed blow-up sketches should be used for scheduled halt locations and other places where confusion is likely to occur. Strip maps are included as an annex to the movement order; if possible, a copy should be provided to all vehicle drivers. See Figure 5-1 for an example of a strip map.

  • 240-240 Figure 5-1. Example strip map.

    Visual Signals

    Because radio silence is observed during most road marches, hand-and-arm signals provide the primary means of passing messages between vehicles.

    Traffic Control

    Road guides and traffic signs may be posted at designated traffic control points by the headquarters controlling the march. At critical points, guides assist in creating a smooth flow of traffic along the march route. Military police, members of the battalion scout platoon, or designated elements from the quartering party may serve as guides. They should have equipment that will allow march elements to identify them during the hours of darkness.

    Actions During the March

    Moving to the Start Point

    The platoon must arrive at the SP at the time designated in the company OPORD. Some companies designate a staging or marshaling area that enables platoons to organize their march columns and conduct final inspections and briefings before movement. Other units require platoons to move directly to the column from their current positions. To avoid confusion during the initial moveout, the platoon leader and TCs conduct a recon-naissance of the route to the SP, issue clear movement instructions, and conduct thorough rehearsals, paying particular attention to signals and timing.

    March Speed

    An element's speed in a march column will vary as it encounters difficult routes and road conditions. This can produce an undesirable accordion effect. The movement order establishes the march speed and maximum catch-up speed. The lead vehicle must not exceed the fixed march speed. In addition, it should accelerate slowly out of turns or choke points; this allows the majority of the platoon to gradually resume the march speed after moving past the restriction.


    Each tank in the platoon has an assigned sector of gun tube orientation (see Figure 5-2). TCs assign sectors of observation to crewmen both to cover their portion of the platoon sector and to achieve 360-degree observation.

    Figure 5-2. Sectors of gun tube orientation.


    While taking part in a road march, the platoon must be prepared to conduct both scheduled and unscheduled halts.

    Scheduled halts. These are conducted to permit maintenance, refueling, and personal relief activities and to allow other traffic to pass. The time and duration of halts are established in the movement order; unit SOP specifies actions to be taken during halts. The first priority at a halt is to establish and maintain local security (see Appendix C). A maintenance halt of 15 minutes is usually taken after the first hour of the march, with a 10-minute break every two hours thereafter.
    During long marches, the unit may conduct a refuel on the move (ROM) operation. Depending on OPSEC considerations and the company OPORD, the platoon may conduct a ROM for all vehicles simultaneously or by section. The OPORD will specify the amount of fuel or the amount of time at the pump for each vehicle. It will also give instructions for OPSEC at the ROM site and at the staging area to which vehicles move after refueling.

    Unscheduled halts. Unscheduled halts are conducted if the unit encounters obstacles or contaminated areas or if a disabled vehicle blocks the route. Whenever an unscheduled halt occurs, each TC sends a messenger to the vehicle to his front; the movement commander must then take action to determine the cause of the halt. A disabled vehicle must not be allowed to obstruct traffic. The crew should move the vehicle off the road immediately, report its status, establish security, and post guides to direct traffic.

    If possible, the crew repairs the vehicle and rejoins the rear of the column. Vehicles that drop out of the column should return to their original positions only when the column has halted. Until then, they move at the rear just ahead of the trail element, which usually comprises the maintenance team with the M88 recovery vehicle and some type of security (the XO will handle security if he is not part of the quartering party). If the crew cannot repair the vehicle, the vehicle is recovered by the trail element.

    Actions on Contact

    If enemy contact occurs during the road march, the platoon executes actions on contact as described in Chapter 3.

    Actions at the Release Point

    The platoon moves through the RP without stopping. The platoon leader picks up the assigned guide or follows the guide's signals to the assembly area. Depending on terrain and the equipment available (GPS or POSNAV), guides and marking materials may be posted at or near exact vehicle locations (see assembly area procedures in the following section).


    An assembly area is a site at which maneuver units prepare for future operations. A well-planned assembly area will have the following characteristics:

      • A location on defensible terrain.
      • Concealment from enemy ground and air observation.
      • Good drainage and a surface that will support tracked and wheeled vehicles.
      • Suitable exits, entrances, and internal roads or trails.
      • Sufficient space for dispersion of vehicles and equipment.

    Normally, a quartering party (also known as an advance party) assists the platoon in the occupation of an assembly area. Established in accordance with company SOP, the quartering party may consist of one or two soldiers from each platoon or even one tank per platoon. It is led by the company XO or 1SG or by a senior NCO. The quartering party takes these actions in preparing the assembly area:

      • Reconnoiter for enemy forces, NBC contamination, condition of the route to the assembly area, and suitability of the area (drainage, space, internal routes). If the area is unsatisfactory, the party contacts the commander and requests permission to find a new location for the site.
      • Organize the area based on the commander's guidance; designate and mark tentative locations for the platoon, trains, and CP vehicles.
      • Improve and mark entrances, exits, and internal routes.
      • Mark and/or remove obstacles (within the party's capabilities).
      • Mark tentative vehicle locations.
    Once the assembly area has been prepared, the quartering party awaits the arrival of the company, maintaining surveillance and providing security of the area within its capabilities. Quartering party members guide their platoons from the RP to their locations in the assembly area. SOPs and prearranged signals and markers (for day and night occupations) should assist the TCs in finding their positions. The key consideration is to move quickly into position to clear the route for other units.

    Once in position, 4. It establishes and maintains security (see the OPSEC discussion in Appendix C) and coordinates with adjacent units. These actions enable the platoon to defend from the assembly area as necessary. The platoon can then prepare for future operations by conducting troop-leading procedures and priorities of work in accordance the company OPORD. Preparations include the following:

      • Establish and maintain security (REDCON status).
      • Conduct troop-leading procedures.
      • Perform maintenance on vehicles and communications equipment.
      • Verify weapon system status; conduct boresighting, MRS updates, test-firing, and other necessary preparations.
      • Conduct resupply, refueling, and rearming operations.
      • Conduct rehearsals and training for upcoming operations.
      • Conduct PCIs.
      • Eat, rest, and conduct personal hygiene activities.

    Normally, the platoon occupies an assembly area as part of a company team. The company team may be adjacent to or independent of the task force (see Figures 5-3A and 5-3B, page 5-10). The company commander assigns a sector of responsibility and weapons orientations for each platoon. If the platoon occupies an assembly area alone, it establishes a perimeter defense (explained later in this chapter).

    In some cases, a company will occupy an assembly area without first sending out a quartering party. During this "occupation by force," the platoon leader orders a hasty occupation of a BP at the platoon's designated location. He establishes local security, directs adjacent unit coordination, begins troop-leading procedures, and establishes priorities of work.

  • 24-24 Figure 5-3A. Assembly area adjacent to other company teams.

  • 1248-1272 Figure 5-3B. Company team assembly area
    independent of the task force.
    Section III. LINKUP

    A linkup is the meeting of friendly ground forces. It may occur in, but is not limited to, the following situations:

      • Advancing forces reaching an objective area previously secured by air assault or airborne forces.
      • Units conducting coordination for a relief in place.
      • Cross-attached units moving to join their new organization.
      • A tank platoon moving forward during a follow and support mission with dismounted infantry or scouts.
      • A unit moving to assist an encircled force.
    Platoons conduct linkup activities independently or as part of a larger force. Within a larger unit, the tank platoon may lead the linkup force. The linkup consists of three phases; the following actions are critical to the execution of a speedy, safe operation:

      • Phase 1 - Far recognition signal. During this phase, the two units should establish communications before they reach direct fire range. The lead element of the linkup force shoul
      • Phase 2 - Coordination and movement to the linkup point. The forces coordinate the following information: known enemy situation; type and number of friendly vehicles; disposition of stationary forces (if either unit is stationary); routes to the linkup point; fire control measures; near recognition signal; finalized location for the linkup point; and any special coordination, such as
      • Phase 3 - Linkup. The units enforce strict fire control measures to help prevent fratricide. If both units are moving, the controlling headquarters designates a location in the formation for the subordinate unit. If one unit is stationary, the moving unit moves through the linkup point to a predetermined location.


    This mission requires the tank platoon to provide the convoy with security and close-in protection from direct fire while on the move. The platoon is well suited for this role because of its vehicles' mobility, firepower, and armor protection against mines and direct and indirect fires. Depending on a variety of factors (size of the convoy, escort assets available, METT-T factors), the platoon may perform convoy escort either independently or as part of a larger unit's convoy security mission.


    Battle command is especially critical because of the task organization of the convoy escort mission. The relationship between the platoon and the convoy commander must provide for unity of command and effort if combat operations are required during the course of the mission. In most cases, the tank platoon will execute the escort mission under control of the security force commander, who is usually OPCON or attached to the convoy commander. At times, however, the platoon will be OPCON or attached directly to the convoy commander. This occurs when the platoon is providing security for tactical operations centers (TOC) or when it is operating independently with a small convoy.

    The convoy commander should issue a complete OPORD to all vehicle commanders in the convoy prior to execution of the mission. This is vital because the convoy may itself be task organized from a variety of units and because some vehicles may not have tactical radios. The order should follow the standard five-paragraph OPORD format, but special emphasis should be placed on the following subjects:

      • Route of march (to include a strip map for each vehicle commander).
      • Order of march.
      • Actions at halts.
      • Actions in case of vehicle breakdown.
      • Actions on contact.
      • Chain of command.
      • Communications and signal information.

    Tactical disposition

    During all escort missions, the convoy security commander and tank platoon leader must establish and maintain security in all directions and throughout the length of the convoy. They can adjust the disposition of the platoon, either as a unit or dispersed, to fit the security requirements of each particular situation. As noted, several factors, including convoy size and METT-T, affect this disposition. Perhaps the key consideration is whether the platoon is operating as part of larger escort force or is executing the escort mission independently.

    Large-scale Escort Missions

    When sufficient escort assets are available, the convoy commander will usually organize the convoy into three distinct elements: advance guard, close-in protective group, and rear guard. Figure 5-4, page 5-14, shows a convoy in which the tank platoon is part of a company team-size escort force.

    The tank platoon will normally be task organized to operate within the close-in protective group. This group provides immediate, close-in protection for the vehicle column, with escort vehicles positioned either within the column or on the flanks. The convoy commander's vehicle is located within this group.

    The advance guard reconnoiters and proofs the convoy route. It searches for signs of enemy activity, such as ambushes and obstacles. Within its capabilities, it attempts to clear the route and provides the convoy commander with early warning before the arrival of the vehicle column. In some cases, an individual tank platoon vehicle, a section, or the entire platoon may be designated as part of the advance guard. The platoon leader may also be required to attach a mine plow or mine roller to this element.

    The rear guard follows the convoy. It provides security in the area behind the main body of the vehicle column, often moving with medical and recovery assets. Again, an individual vehicle, a section, or the entire tank platoon may be part of this element.

    NOTE: The convoy commander may also designate the tank platoon as part of a reserve (reaction) force for additional firepower in the event of enemy contact. The reserve will either move with the convoy or be located at a staging area close enough to provide immediate interdiction against the enemy.

  • 120-120

    Figure 5-4. Tank platoon as part of larger escort force.
    When the platoon is deployed as a unit during a large-scale escort operation, it can provide forward, flank, or rear close-in security. In such situations, it executes tactical movement based on the factors of METT-T. Figures 5-5A through 5-5C (pages 5-15 and 5-16) show the platoon using various formations while performing escort duties as a unit.
  • 72-72-72-72
    Figure 5-5A. Platoon performing forward security for a convoy.

  • 480-480-288-528

    Figure 5-5B. Platoon performing flank security for a convoy.

  • 480-480-240-192
    Figure 5-5C. Platoon performing rear security for a convoy.

    Independent Escort Operations

    When the tank platoon executes a convoy escort mission independently, the convoy commander and platoon leader will disperse the tanks throughout the convoy formation to provide forward, flank, and rear security. Whenever possible, wingman tanks should maintain visual contact with their leaders. Tanks equipped with mine plows or mine rollers (and engineer assets, if available) should be located near the front to respond to obstacles. At times, these assets may be required to move ahead of the convoy, acting as the reconnaissance element or moving with scouts to proof the convoy route. Figure 5-6 illustrates this kind of escort operation.

    Figure 5-6. Platoon performing convoy escort independently.
    In some independent escort missions, variations in terrain along the route may require the platoon to operate using a modified traveling overwatch technique. Figure 5-7 illustrates such a situation. It shows one section leading the convoy while the other trails the convoy. Dispersion between vehicles in each section is sufficient to provide flank security. Depending on the terrain, the trail section may not be able to overwatch the movement of the lead section.
  • 600-600-48-192
    Figure 5-7. Platoon escort using modified traveling overwatch.

    Actions on contact

    As the convoy moves to its new location, the enemy may attempt to harass or destroy it. This contact will usually occur in the form of an ambush, often with the use of a hastily prepared obstacle. The safety of the convoy then rests on the speed and effectiveness with which escort elements can execute appropriate actions on contact.

    Based on the factors of METT-T, portions of the convoy security force, such as the tank platoon or a tank section, may be designated as a reaction force. The reaction force performs its escort duties, conducts tactical movement, or occupies an assembly area as required until enemy contact occurs; it then is given a reaction mission by the convoy commander.

    Actions at an Ambush

    An ambush is one of the most effective ways to interdict a convoy. Conversely, reaction to an ambush must be immediate, overwhelming, and decisive. Actions on contact must be planned for and rehearsed so they can be executed as a drill by all escort and convoy elements, with care taken to avoid fratricide.

    In almost all situations, the platoon will take several specific, instantaneous actions when it must react to an ambush. These steps, illustrated in Figures 5-8A and 5-8B, include the following:

      • As soon as they acquire an enemy force, the escort vehicles action toward the enemy (Figure 5-8A). They seek covered positions between the convoy and the enemy and suppress the enemy with the highest possible volume of fire permitted by the ROE. Contact reports are submitted to higher headquarters as quickly as possible.
      • The convoy commander retains control of the convoy vehicles and continues to move them along the route at the highest possible speed (Figure 5-8A).
      • Convoy vehicles, if they are armed, may return fire only if the escort has not positioned itself between the convoy and the enemy force.
      • The platoon leader or the convoy commander may request that any damaged or disabled vehicles be abandoned and pushed off the route (Figure 5-8B).
      • The escort leader (in the example included here, this is the tank platoon leader) uses SPOTREPs to keep the convoy security commander informed. If necessary, the escort leader or the convoy security commander can then request support from the reaction force; he can also call for and adjust indirect fires.
  • 168-144
    Figure 5-8A. Convoy escort actions toward ambush.

  • 144-144-216-144
    Figure 5-8B. Convoy continues to move.
    Once the convoy is clear of the kill zone, the escort element executes one of the following courses of action based on the composition of the escort and reaction forces, the commander's intent, and the strength of the enemy force:

      • Continue to suppress the enemy as combat reaction forces move to support (see Figure 5-9A).
      • Assault the enemy (see Figure 5-9B).
      • Break contact and move out of the kill zone (see Figure 5-9C).

    In most situations, tanks will continue to suppress the enemy or execute an assault. Contact should be broken only with the approval of the tank platoon's higher commander.
  • 72-72Figure 5-9A. Escort suppresses ambush for
    reaction force attack.
  • 96 Figure 5-9B. Escort assaults ambush.

    Figure 5-9C. Escort breaks contact.

    Actions at an Obstacle

    Obstacles are a major threat to convoys. The purpose of the route reconnaissance ahead of a convoy is to identify obstacles and either breach them or find bypasses. In some cases, however, the enemy or its obstacles may avoid detection by the reconnaissance element. If this happens, the convoy must take actions to reduce or bypass the obstacle.

    Obstacles can be used to harass the convoy by delaying it; if the terrain is favorable, the obstacle may be able to stop the convoy altogether. In addition, obstacles may canalize or stop the convoy to set up an enemy ambush. When an obstacle is identified, the convoy escort faces two problems: reducing or bypassing the obstacle and maintaining protection for the convoy. Security becomes critical, and actions at the obstacle must be accomplished very quickly. The convoy commander must assume that the obstacle is overwatched and covered by the enemy.

    To reduce the time the convoy is halted and thus to reduce its vulnerability, the following actions should occur when the convoy escort encounters a point-type obstacle:

      • The lead element identifies the obstacle and directs the convoy to make a short halt and establish security. The convoy escort overwatches the obstacle (see Figure 5-10) and requests that the breach force move forward.
      • The convoy escort maintains 360-degree security of the convoy and provides overwatch as the breach force reconnoiters the obstacle in search of a bypass.
      • - Bypass the obstacle.
      • Breach the obstacle with the assets on hand.
      • Breach the obstacle with reinforcing assets.
      • The convoy security commander relays a SPOTREP higher and requests support by combat reaction forces, engineer assets (if they are not part of the convoy), and aerial reconnaissance elements.
      • Artillery units are alerted to be prepared to provide fire support.

  • 72-48
    Figure 5-10. Convoy escort overwatches an obstacle.

    Tanks equipped with mine plows are ideal for breaching most obstacles encountered during convoy escort missions. If the convoy escort is required to breach limited obstacles using plow tanks, the platoon leader must maintain the security of the convoy, ensuring that adequate support forces are in place to overwatch the breach operation.

    Actions during halts

    During a short halt, the convoy escort remains at REDCON-1 regardless of what actions the convoy vehicles are taking (refer to Appendix C for more information on REDCON levels). If the halt is for any reason other than an obstacle, the following actions should be taken:

      • · If possible, escort vehicles are positioned up to 100 meters beyond the convoy vehicles, which are just clear of the route (see Figure 5-11A). Escort vehicles remain at REDCON-1 but establish local security based on the factors of METT-T.
      • When the order is given to move out, convoy vehicles reestablish the movement formation, leaving space for escort vehicles (see Figure 5-11B). Once the convoy is in column, local security elements (if used) return to their vehicles, and the escort vehicles rejoin the column (refer to Figure 5-11C).
      • When all elements are in column, the convoy resumes movement.

  • 240-240-144-144
    Figure 5-11A. Convoy assumes herringbone formation.
  • 312-240-24 Figure 5-11B. Convoy moves back into column formation.

  • 475-245Figure 5-11C. Convoy escort vehicles rejoin column.

    The tank platoon participates in a passage of lines, in which one unit moves through the stationary positions of another, as part of a larger force. If it is part of the stationary force, the platoon occupies defensive positions and assists the passing unit. If it is part of a passing unit, the platoon executes tactical movement through the stationary unit. A passage may be forward or rearward.

    Units are highly vulnerable during a passage of lines. Vehicles may be concentrated, and fires may be masked. The passing unit may not be able to maneuver and react to enemy contact.

    Detailed reconnaissance and coordination are critical in overcoming these potential problems and ensuring the passage of lines is conducted quickly and smoothly. The commander normally conducts all necessary reconnaissance and coordination for the passage. At times, he may designate the XO, 1SG, or a platoon leader to conduct liaison duties for reconnaissance and coordination. The following items of information are coordinated (an asterisk indicates items that should be confirmed by reconnaissance):

      • Unit designation and composition; type and number of passing vehicles.
      • Passing unit arrival time(s).
      • Location of attack positions or assembly areas. *
      • Current enemy situation.
      • Stationary unit's mission and plan (to include OP, patrol, and obstacle locations). *
      • Location of contact points, passage points, and passage lanes. (NOTE: The use of GPS/POSNAV waypoints will simplify this process and, as a result, speed the passage.) *
      • Guide requirements.
      • Order of march.
      • Anticipated and possible actions on enemy contact.
      • Supporting direct and indirect fires, including location of the restrictive fire line (RFL). *
      • NBC conditions.
      • Available CS and CSS assets and their locations. *
      • Communications information (to include frequencies, digital data, and near and far recognition signals).
      • Chain of command, including location of the battle handover line (BHL).
      • Additional procedures for the passage.

    Forward passage of lines

    During the forward passage, the passing unit first moves to an assembly area or an attack position behind the stationary unit. Designated liaison personnel move forward to link up with guides and confirm coordination information with the stationary unit. Guides then lead the passing elements through the passage lane.

    The tank platoon conducts tactical movement to maximize its battle space within the limitations of the passage lane. Radio traffic is kept to a minimum. Disabled vehicles are bypassed. The platoon holds its fire until it passes the RFL. Once clear of passage lane restrictions, the platoon conducts tactical movement in accordance with its orders.

    Rearward passage of lines

    Because of the increased chance of fratricide during a rearward passage, coordination of recognition signals and direct fire restrictions is critical. The passing unit contacts the stationary unit while it is still beyond direct fire range and conducts coordination as discussed previously. RFLs and near recognition signals are emphasized.

    The passing unit then continues tactical movement toward the passage lane. Gun tubes are oriented on the enemy, and the passing unit is responsible for its own security until it passes the RFL. If guides are provided by the stationary unit, the passing unit may conduct a short halt to link up and coordinate with them. The passing unit moves quickly through the passage lane to a designated location behind the stationary unit.

    Assisting a passage of lines

    As noted, the platoon provides this assistance while it is in stationary defensive positions. This can occur after the platoon has consolidated on an objective or has occupied a BP. Coordinating instructions may be in the form of a company OPORD or a FRAGO issued over the radio. The platoon leader may or may not have coordinated directly with the passing unit.

    The platoon leader ensures that the platoon understands the points of coordination listed previously in this section. If the platoon is to provide guides to assist the passing unit, he selects the personnel and briefs them on the points of coordination. The guides are responsible for linking up with and guiding the passing unit through the passage lane and for closing obstacles as necessary.

    Control of direct fires is a critical role for the element that is assisting the passage of lines. In a forward passage, the stationary unit engages known enemy targets until the passing unit moves past the RFL (sometimes designated as the BHL). During a rearward passage, the passing unit contacts the stationary unit by radio at a point beyond the direct fire range of weapon systems. The stationary unit then holds all fires until the passing unit reaches the RFL.


    Obstacles are any obstructions that stop, delay, divert, or restrict movement. They are usually covered by observation and enhanced by direct or indirect fires. There are two categories of obstacles.

    Existing Obstacles

    These are already present on the battlefield and are not emplaced through military effort. They may be natural or man-made. Examples of natural obstacles include the following: ravines, gullies, gaps, or ditches over 3 meters wide; streams, rivers, or canals over 1 meter deep; mountains or hills with a slope in excess of 60 percent (30 degrees); lakes, swamps and marshes over 1 meter deep; tree stumps and large rocks over 18 inches high; and forests or jungles with trees 8 inches or more in diameter and with less than 4 meters of space between trees on a slope. Man-made obstacles include built-up areas such as towns, cities, or railroad embankments.

    Reinforcing Obstacles

    Placed on the battlefield through military effort, these are designed to slow, stop, or canalize the enemy. Whenever possible, both friendly and enemy forces will enhance the effectiveness of their reinforcing obstacles by tying them in with existing obstacles. Examples of reinforcing obstacles are examined in the following paragraphs.

    The minefield is the most common reinforcing obstacle the platoon will encounter on the battlefield. It is easier and quicker to emplace than other obstacles and can be very effective in destroying vehicles. The minefield may be emplaced in several ways: by hand, by air or artillery delivery using the family of scatterable mines (FASCAM), or by mechanical means (the Volcano system). It can be used separately or in conjunction with other obstacles (refer to Figure 5-12, pages 5-30 and 5-31, for possible minefield locations).

    Figure 5-12. Potential minefield locations.

    Figure 5-12. Potential minefield locations (continued).

    The antitank ditch, illustrated in Figure 5-13, may be reinforced with wire and/or mines to make it more complex and more difficult for the attacker to overcome. In addition, soil from the ditch can be built up into a berm on the emplacing unit side.

    Figure 5-13. Antitank ditch.

    Road craters can be rapidly emplaced and are especially effective where restrictive terrain on the sides of a road or trail prevents a bypass (refer to Figure 5-14). Craters are at least 1.5 meters in depth and 6 meters in diameter and are usually supplemented with mines and/or wire.

    Figure 5-14. Road craters.
    An abatis provides an effective barrier against vehicle movement. Trees are felled either by sawing or by use of explosives; the cut is made at least 1.5 meters above the ground, with the main trunks crisscrossed and pointed toward the enemy at approximately a 45-degree angle. The abatis is usually about 75 meters in depth and ideally is located on trails where there is no bypass; the trunk of each tree should remain attached to the stump to form an obstacle on the flanks of the abatis (see Figure 5-15). Abatises are usually mined or booby-trapped.

    Figure 5-15. Abatis.

    A log crib is a framework of tree trunks or beams filled with dirt and rock (see Figure 5-16, page 5-34). They are used to block roads or paths in wooded and mountainous terrain.

    Wire obstacles are an effective and flexible antipersonnel barrier; they are frequently employed on dismounted avenues of approach in the form of tanglefoot, double- or triple-strand concertina, and four-strand fences. Employed in depth or in conjunction with mines, wire obstacles are also very effective against tanks and similar vehicles (see Figure 5-17). A single wire obstacle, however, will have little effect on armored vehicles; the sprocket of M1-series tanks is designed to cut wire.

    Figure 5-16. Log cribs.

    Figure 5-17. Wire obstacle in depth.
    A tank wall or tank berm is constructed of dirt and rock to slow or canalize enemy tanks; it also gives the defender "belly" shots while the attacker is unable to engage (see Figure 5-18).

    Figure 5-18. Belly shot created by tank berm.

    Breaching procedures

    Breaching operations entail the coordinated efforts of three task organized elements: the support force, the breach force, and the assault force. The discussion in this section covers the actions and responsibilities of these elements as well as the tank platoon's role in the operation.

    The following actions, known by the abbreviation SOSR, occur during a breaching operation:

      • Sufficient support elements are employed to suppress enemy elements that are overwatching the obstacle. The support force uses direct and indirect fires to accomplish its mission.
      • The support force requests immediate or preplanned smoke to obscure breach force operations.
      • The breach force creates and proofs a lane through the obstacle, allowing the assault force to secure the far side of the obstacle.
      • Actions taken to further mark and reduce the obstacle allow follow-on forces to continue the attack.

    Support Force

    The support force usually leads movement of the breach elements. After identifying the obstacle, it moves to covered and concealed areas and establishes support by fire positions. The support force leader sends a voice or digital SPOTREP to the commander. This report must describe the location and complexity of the obstacle, the composition of enemy forces that are overwatching the obstacle, and the location of possible bypasses. The commander decides whether to maneuver to a bypass or to breach the obstacle. (NOTE: He must keep in mind that a bypass may lead to an enemy kill zone.)

    In either case, the support force suppresses any enemy elements that are overwatching the obstacle to allow the breach force to breach or bypass the obstacle. The support force should be in position to request suppressive artillery fires and smoke for obscuration. As the breach and assault forces execute their missions, the support force lifts and shifts supporting fires. Because the enemy is likely to engage the support force with artillery, the support force must be prepared to move to alternate positions while maintaining suppressive fires.

    Breach Force

    The breach force receives the location of the obstacle or bypass by means of a voice or digital SPOTREP. It then must organize internally to perform these responsibilities:

      • Provide local security for the breach site as necessary.
      • Conduct the actual breach, creating, proofing, and marking a lane through the obstacle or bypass.
      • Move through the lane to provide security for the assault force on the far side of the obstacle. In some instances, the breach force may move to hull-down firing positions that allow it to suppress enemy elements overwatching the obstacle. At other times, it may assault the enemy, with suppressive fires provided by the support force.
    A tank platoon can create a lane by itself if it is equipped with the assets required to breach the type of obstacle encountered. If the platoon does not have this capability, it may be required to provide close-in protection for attached engineers with breaching assets. Three breaching methods are available to the platoon:

      • Mechanical breaching, usually with mine plows or mine rakes.
      • Explosive breaching, employing such means as the mine-clearing line charge (MICLIC), M173 line charge, or 1/4-pound blocks of TNT.

      • Manual breaching, with soldiers probing by hand or using such items as grappling hooks, shovels, picks, axes, and chain saws. Manual breaching is the least preferred method for the tank platoon.

    NOTE: In extreme cases, the commander may order the platoon to force through an obstacle. This technique requires the breach force to move in column formation through the obstacle location. If available, a disabled vehicle can be pushed ahead of the lead breach vehicle in an attempt to detonate mines.

    The mine plow is the breaching device most commonly employed by the tank platoon. The battalion or company commander may allocate one to three plows per platoon. When properly equipped and supported, the platoon can create up to two lanes through an obstacle.

    Plow tanks lead the breach force. Immediately following them are vehicles that proof the lane; these are usually tanks equipped with mine rollers. This process ensures that the lane is clear. (NOTE: If the location and/or dimensions of the obstacle are unknown, the platoon leader may choose to lead with tanks equipped with mine rollers to identify the beginning of the obstacle.)

    If the platoon is allocated one plow, the PSG's wingman normally serves as the breach tank. The PSG follows immediately behind to proof the lane and provide overwatch. The platoon leader's section follows the PSG.

    If the platoon has two or more plows, it can create multiple lanes, usually 75 to 100 meters apart. The wingman tanks are normally equipped with the plows, with the section leaders' tanks following to proof the lanes and provide overwatch (see Figure 5-19A).

    Figure 5-19A. Plow tanks create multiple lanes while the section leaders' tanks provide overwatch.

    To create a wider lane, two plow tanks can stagger their movement along a single lane (see Figure 5-19B). An alternative method is for a plow tank to complete its initial pass through the obstacle, then to turn around and move back toward the friendly side to widen the lane or create a new lane.
    Figure 5-19B. Plow tanks use staggered movement
    to create a wider lane.

    After the lane is created and proofed, it can then be marked to ensure safe movement by vehicles and personnel; this is critical for follow-on forces that may not know the exact location of the cleared lane. Distinctive markers must show where the lane begins and ends. A visible line down the center is effective. Another technique is to mark both sides of the breached lane. Figure 5-20, page 5-40, shows a sample marking method. To minimize the necessary breaching time, the proofing vehicle may simultaneously mark the lane. Unit SOPs will dictate marking methods and materials, which commonly include the following:

      • Cleared lane mechanical marking system (CLAMMS).
      • Pathfinder system.
      • Engineer stakes with tape.
      • Guides.
      • Chem lights.
      • Expended shell casings.
    Figure 5-20. Sample technique for obstacle lane marking.

    Throughout the operation, the platoon leader provides continuous updates of the breach force's progress to higher headquarters and other elements involved in the breach. He also coordinates with the support force for suppressive fires.

    After marking is complete, the platoon leader uses voice and digital systems to report the location of the lane and the method of marking to expedite the movement of the assault force. Digital overlays enable units to move quickly to the breach lanes using the POSNAV or GPS. (NOTE: The assault force will often move behind the breach force and closely follow the breach vehicles through the new lane.)

    Assault Force

    While the breach is in progress, the assault force assists the support force or follows the breach force while maintaining cover and dispersion. Once a lane is cleared through the obstacle, the assault force moves through the breach. It secures the far side of the obstacle by physical occupation and/or continues the attack in accordance with the commander's intent. Tank units are ideally suited for assault force operations against mobile enemy defenses in open terrain. Tanks also work well with mechanized infantry as an assault force attacking dug-in enemy positions in close terrain.


    The tank platoon conducts follow and support missions when the enemy situation is extremely fluid or unknown. Normally, it executes the mission in support of dismounted infantry or scout platoons. On rare occasions, the platoon will follow and support other tank platoons or mechanized forces.

    During the follow phase of the mission, the platoon conducts tactical movement or occupies hasty BPs while the lead (supported) element moves. There is no requirement to overwatch the movement of the lead element. In fact, this could be counterproductive; for example, the noise of a tank platoon that is following too closely could alert the enemy to the presence of the supported scout platoon or dismounted infantry. The tank platoon does, however, maintain a high degree of situational awareness. It maintains communications with the lead element, either by transmitting on a higher net or by monitoring the supported unit's net.

    When the lead element makes contact with an enemy force it cannot destroy or bypass, it requests the support of the tank platoon to destroy or suppress the enemy. Based on the request, the platoon conducts linkup and coordination, then executes an offensive course of action as discussed in Chapter 3 of this manual. Appendix B contains additional information on light/heavy operations involving the tank platoon and dismounted (light) infantry.


    The perimeter defense is conducted in the same manner as a defense from a BP (hasty or deliberate) except that it orients on a full 360-degree sector, normally through use of the coil formation (see Chapter 3). The purpose of the perimeter defense is to protect the force or hold key terrain when the force is not tied in with adjacent units. Common situations for the use of the perimeter defense include the following:

      • Defense of assembly areas.
      • Defense of specific installations or equipment (such as a TOC, downed aircraft, bridge, or roadblock).
      • Defense of key terrain (such as a bridge, hilltop, pickup zone, or landing zone).
      • When a unit has been isolated or bypassed by the enemy.
      • As part of a larger force's perimeter defense; examples include the defense of lodgement areas, airfields, or assembly areas.

    The tank platoon will normally execute a perimeter defense while attached to company- or battalion-size dismounted infantry units. The platoon may also establish a perimeter defense when it is operating alone and requires 360-degree security, such as during screen missions or while occupying platoon hide positions. Considerations for the execution of a perimeter defense include the following:

      • One section or the entire platoon orients on the most likely mounted avenues of approach.
      • A section or the entire platoon may occupy an assembly area within the perimeter as a reserve or reaction force. Missions of this force include moving to BPs that block potential areas of enemy penetration, conducting counterattacks to destroy an enemy penetration, and moving to BPs that add firepower to a portion of the defense.
      • To avoid disrupting other fighting positions, the platoon must carefully coordinate, reconnoiter, and conduct rehearsals on mounted movement routes to positions within the perimeter.
      • Tanks must never fire over the heads of unprotected personnel. The concussion of the main gun as well as discarded sabot petals can endanger these troops.
      • .

    Section IX. SCREEN

    The screen is a common security mission for cavalry troops and company teams. Cavalry troops conduct stationary or moving flank screens. Company teams usually establish screen lines (for counterreconnaissance purposes) in front of a task force as part of a defense. Purposes of the screen include the following:

      • Provide early warning of enemy approach.
      • Provide real-time information, reaction time, and maneuver space to the protected force.
      • Impede and harass the enemy.
      • Facilitate counterreconnaissance operations, allowing the screening force, within its capability, to destroy enemy reconnaissance elements.

    During stationary screens, the tank platoon will normally occupy a hide position or a hasty defensive position in depth behind OPs. The OPs are provided by scout or mechanized infantry platoons. When the OPs identify the enemy, the commander issues FRAGOs for the tank platoon to conduct tactical movement and occupy a hasty defensive position or an attack by fire position; the platoon also may conduct a hasty attack to destroy the enemy. At times, the tank platoon may occupy a hasty BP as part of the screen line, acquiring and killing the enemy forward of the position. During the conduct of a stationary screen, the tank platoon may be required to break contact or conduct a withdrawal and then execute a passage of lines. These tasks are discussed in other sections of this chapter.

    In a moving flank screen (platoons normally execute this as a follow and support operation, discussed earlier in this chapter), the tank platoon conducts tactical movement to the rear of scout platoons. It may periodically occupy hasty BPs. When the scouts identify enemy elements, the commander issues a FRAGO for the tank platoon to occupy a hasty defensive position or attack by fire position or to conduct a hasty attack to destroy the enemy.

    It is critical that the tank platoon leader keep these considerations in mind during all screen operations:

      • OPSEC requirements. During screen missions, the platoon may be required to operate apart from other units.
      • Location and identification of friendly forces. The platoon leader should know all patrol routes and OP locations within the platoon's battle space. The platoon should maintain voice and digital (if available) communications with the OPs.
      • Engagement criteria. To reduce the potential for fratricide, engagement criteria should be as specific as possible when friendly units operate to the front and flanks of the tank platoon as it executes a screen mission.

    Section X. DELAY

    The delay is a continuous series of defensive actions over successive positions in depth. The purpose is to trade the enemy space for time while retaining freedom of action. Tank teams involved in a delay operation maximize the use of terrain and obstacles, maintaining contact with the enemy but avoiding decisive engagement. In some instances, local counterattacks are used to assist units during a disengagement or to take advantage of battlefield opportunities.

    The tank platoon conducts the delay as part of a company team. In some cases, it will occupy either a hasty or deliberate BP; it will then disengage and occupy subsequent BPs in depth as part of the delaying force. The platoon may also be required to conduct local counterattacks or to support the movement of other platoons during the delay. The considerations involved in planning and executing a delay at platoon level are the same as for offensive operations (refer to Chapter 3) and defensive operations (refer to Chapter 4).


    A relief in place occurs when one unit assumes the mission of another unit. It may be accomplished during either offensive or defensive operations, preferably during periods of limited visibility.

    A relief requires detailed planning. OPSEC is critical. When time is available and the situation permits, the incoming platoon leader coordinates with the in-place platoon leader and conducts a reconnaissance to confirm details of the relief. The two leaders should coordinate and exchange the following information:

      • The enemy situation and other pertinent intelligence.
      • The platoons' maneuver and fire support plans.
      • The location of weapons and fighting positions.
      • Sketch cards and fire plans (this includes grid locations for input into digital systems).
      • Details of the relief, to include the sequence, the use of recognition signals and guides, and the time of change of responsibility for the area.
      • The transfer of excess ammunition, POL, wire lines, and other materiel to the incoming unit.
      • Command and signal information.

    Reconnaissance of the position is the same as for any BP. The incoming platoon leader should note the following:

      • The engagement area, to include decision points, trigger lines, TRPs, obstacles, and the break point.
      • Primary, alternate, and supplemental fighting positions.
      • Routes to and within the BP.
      • Hide positions.
      • Location of guides.

    After reconnaissance and coordination are complete, the platoon leaders continue with their troop-leading procedures and prepare to execute the relief. There are two methods by which to conduct a relief in place:

      • Simultaneous. All elements are relieved simultaneously.
      • Sequential. The relief takes place one element at a time (by individual vehicle or by section).
    Initially, the relieving unit moves to an assembly area behind the unit to be relieved. Final coordination is conducted, and information is exchanged between the two units. The relieving unit links up with guides or finalizes linkup procedures. Individual vehicles then relieve forward positions using one of three techniques:

      • The relieving vehicles occupy primary positions after the relieved unit has moved to alternate positions. Once OPs are in place, the relieved unit can withdraw.
      • The relieving vehicles occupy alternate positions while the relieved unit remains in primary positions. Once OPs are in place, the relieved unit withdraws. The platoon leader then orders the relieving unit to occupy primary positions as necessary.
      • The relieving unit occupies a hide position while the relieved unit occupies hide, primary, or alternate positions. Once OPs are in place, the relieved unit withdraws.

    As noted, OPSEC is critical in preventing enemy reconnaissance and intelligence assets from identifying the weaknesses and vulnerabilities that occur during the relief. Net discipline is the key to an effective, and secure, relief operation. Before beginning the relief, the relieving unit changes to the outgoing unit's frequency, and the two units operate on the same net throughout the relief. The incoming unit observes radio listening silence while the outgoing unit maintains normal radio traffic.

    By monitoring the same frequency and maintaining digital links, leaders at all levels have the ability to contact other units involved in the relief to warn of emergency situations, such as enemy contact. Because of the proximity of the relieved and relieving elements, however, leaders must remember that the net will be crowded, with many stations and digital links competing for limited availability of "air time."

    Once the relief is complete, there are two methods for returning to separate unit frequencies. One technique is to have the incoming unit switch back to its original frequency. The other is to have the outgoing unit switch to an alternate frequency. There are several advantages for the latter technique:

      • The relieving unit establishes voice and digital communications and is prepared to defend immediately upon the exit of the relieved unit.
      • The relieving unit never loses the digital link (if applicable) as it assumes the new mission. Once the relief is complete, the relieved unit simply logs off the digital net and switches to an alternate FM frequency; it can then reestablish a digital link after leaving the relief site.
      • Maintaining radio traffic on the same frequency before, during, and after the operation will help deceive the enemy as to whether a relief has occurred.


    The purpose of this retrograde operation is to free a force in contact with the enemy so it can execute a new mission. Conducting a withdrawal at platoon level is identical to disengagement (see Chapter 4). The withdrawal may be conducted under pressure (with direct or indirect fire enemy contact) or with no pressure.

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