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Tactical minefields are considered tactical obstacles and follow the same basic integration principles. Tactical obstacle C 2 focuses on obstacle emplacement authority and obstacle control.


Obstacle emplacement authority is the jurisdiction that a unit commander has to emplace tactical obstacles. In a theater of operations (TO), theater commanders have the authority to emplace obstacles. In most cases, they delegate that authority to corps commanders who further delegate it to division commanders. Division commanders then have obstacle emplacement authority in their area of operations (AO), unless the authority is subsequently withheld or restricted by a higher commander. Commanders subordinate to corp and division do not have the authority to emplace obstacles unless the higher commander delegates authority for a current operation. Commanders use control measures and other specific guidance or orders to grant obstacle emplacement authority to subordinate commanders. Emplacement authority for SCATMINEs is covered in Chapter 3.


Commanders exercise obstacle control to ensure that obstacles support current and future operations. Obstacle control ensures that subordinate commanders emplace obstacles to best support the higher commander's scheme of maneuver. It also ensures that subordinate commanders do not interfere with future operations. Commanders maintain obstacle control by focusing or withholding emplacement authority or by restricting the types or locations of obstacles. Commanders use control measures, specific guidance, and orders to maintain obstacle control.


Obstacle control measures are specific control measures that simplify granting obstacle emplacement authority and providing obstacle control for all levels of command (Table 2-1). Obstacle control measures are classified as--

  • Zone.
  • Belt.
  • Group.
  • Restriction.

Table 2-1. Echelons of obstacle control and effect

Obstacle Control
Echelon Specific Obstacle Effects Assigned Size of Enemy AA/MC Planning Guidance
Armored Light vs Armored
Zone Corps or division Optional Division/brigade Brigade/battalion Requires anticipating belts and intents
Belt Brigade Optional but normal Brigade/battalion Battalion/company Requires anticipating groups and intents
Group Corps, brigade, division, or battalion/TF Mandatory Battalion/TF Company/platoon Based on individual obstacle norms
Restriction All NA NA NA Used only when necessary to support the scheme of maneuver

A protective obstacle is the only obstacle that can be employed outside a designated obstacle zone, belt, or group.

A specific obstacle effect (disrupt, turn, fix, or block) may be assigned to obstacle control measures. This enables the commander to direct the overall effect of obstacles within a designated zone, belt, or group to support his plan. At corps and division levels, assigning specific effects to obstacle zones is optional. At brigade level, the commander will normally assign a specific effect to the obstacle belts. At TF and battalion levels, obstacle effects for obstacle groups are required. This ensures that subordinate commanders emplace tactical obstacles that support the maneuver and fire plans. Assigning a specific obstacle effect to a control measure becomes obstacle intent, giving the obstacle effect, target, and location. Obstacle intent provides a direct link between the obstacle plan, the scheme of maneuver, the commander's intent, and the fire plan (direct and indirect). Obstacle intent is critical at brigade level and below, and it becomes the foundation for obstacle group development and design at the TF level.

Obstacle Zones

Obstacle zones (Figure 2-9) are graphic control measures that corps and division commanders use to grant obstacle emplacement authority to brigades (including armored cavalry regiments [ACRs] and other major subordinate units). Corps and division commanders use zones to ensure that subordinates emplace obstacles that support the higher commander's scheme of maneuver, and to ensure that the obstacles do not interfere with future operations.

Figure 2-9. Obstacle zones

Obstacle Belts

Obstacle belts (Figure 2-10) are graphic control measures that brigade commanders use to constrain tactical-obstacle employment, and the belts should not cross unit boundaries. Commanders plan obstacle belts within assigned obstacle zones to grant obstacle emplacement authority to their major subordinate units. This is normally the first level in which the commander assigns an intent to the obstacle plan. It gives TF commanders the necessary guidance on the overall effect of obstacles within a belt. It does not designate that all obstacle groups within the belt must be the same effect. It simply means that the sum effect of groups within the belt must achieve the assigned belt effect. This serves to synchronize the obstacle effort within the brigade, particularly between adjacent TFs. Obstacle belts also focus obstacles in support of the brigade scheme of maneuver and ensure that obstacles do not interfere with the maneuver of any higher headquarters.

Figure 2-10. Obstacle belts

Belts are planned to attack enemy regiments based on an analysis of enemy battalion MCs. Brigades allocate maneuver companies based on the motorized rifle battalion (MRB) AAs and organize TFs to defeat the motorized rifle regiment (MRR). Obstacle belts and their intents are directed against MRR AAs. This provides the appropriate level of guidance while preserving the TF's need to refine the obstacle intent, based on how the TF will fight its allocated companies.

Obstacle Groups

Obstacle groups (Figure 2-11) contain one or more individual obstacles that are grouped together to provide a specific obstacle effect. TFs use obstacle groups to ensure that company teams emplace individual obstacles that support the TF scheme of maneuver. In rare cases, brigades, divisions, or even corps may use obstacle groups for specific tactical obstacles. Also, units perform detailed integration of obstacle groups with direct- and indirect-fire plans.

Figure 2-11. Obstacle groups

A TF allocates platoons against motorized rifle company (MRC) MCs and task-organize them into companies/teams to defeat MRBs. Likewise, direct-fire plans are designed based on the maneuver of MRBs and independent MRCs. Therefore, obstacle groups are used to attack the maneuver of MRB-size forces. Groups are designed specifically to support the direct-fire plan of the TF. The TF designates groups rather than obstacles because the location of individual obstacles hinges on siting at the company/team level. The group effect or obstacle intent drives obstacle siting and is therefore more important to convey to commanders. There can be more than one type of obstacle group to support the overall intent of an obstacle belt. This is because the belt design is based on the brigade's scheme of maneuver, without knowing the TF's direct-fire plan and scheme of maneuver. Groups are developed once the fire plan is established.

Obstacle Restrictions

Commanders at all levels may use obstacle restrictions to provide additional obstacle control. They may use obstacle restrictions to limit the specific types of obstacles used (for example, no buried mines and no SCATMINEs that do not self-destruct within 48 hours). These restrictions ensure that subordinates do not use obstacles with characteristics that impair future operations. It also allows commanders to focus the use of limited resources for the main effort by restricting their use elsewhere. Commanders may also use restrictions to prevent subordinates from emplacing obstacles in a certain area. This type of restriction may be shown graphically as an obstacle-restricted area.


The modern tendency toward maneuver warfare and the disappearance of the linear battlefield places repositioning forces at an increased risk of fratricide by minefields. Obstacle control and the use of graphic obstacle control measures are vital in preventing minefield fratricide at every echelon. Obstacle control is further facilitated by positive C 2 of all sustainment traffic, tactical repositioning, obstacle turnover, well-established and disseminated traffic plans with traffic control, and strict adherence to minefield marking procedures (discussed later in this chapter).


Commanders include obstacle planning in each level of the decision-making process. This ensures that obstacle integration is effective and that the obstacle plan is flexible enough to allow changes during the planning, preparation, and execution phases of an operation. The following method is used to integrate obstacle planning at the TF level; it uses the decision-making doctrine contained in FM 101-5. Obstacle planning for brigade and higher levels can be found in FM 90-7.

The focus of obstacle planning is to integrate obstacles into the maneuver direct- and indirect-fire plans. This planning is directive and detailed in nature and focuses on the determination of obstacle groups and the type and amount of prepared positions. Actual obstacle siting, emplacement, and position location are the purview of the company/team commander and are normally supported by an engineer platoon.

TF-level defensive planning is part of the military decision-making process. The engineer battlefield assessment (EBA) process provides the basis for integrating engineer issues into the decision-making process.

Mission Analysis

The key activities during mission analysis are to--

  • Determine facts and assumptions.
  • Analyze relative combat power.
  • Analyze the engineer battalion's/brigade's mission and the commander's intent.
  • Issue the commander's guidance.

Determine Facts and Assumptions

Defensive planning normally starts with the receipt of a warning order (WO) from the higher headquarters to defend. The company executive officer (XO) and the battlefield information control center (BICC) (or the TF engineer and the Intelligence Officer [US Army] [S2]) begin by developing a situation template (SITEMP) that includes a modified combined obstacle overlay (MCOO). The MCOO is a product developed during the intelligence preparation of the battlefield (IPB) process. The MCOO development is a joint effort of the engineer and the intelligence section of the TF's tactical operations center (TOC).

The MCOO should define the AAs and the MCs within the TF's AO. This information is vital to obstacle planning. Obstacles are placed on AAs to attack enemy maneuver. The AA analysis details potential EAs and indicates where forces can defend with limited survivability construction, because a reverse slope or undulating terrain provides natural concealment and cover.

The threat evaluation and the enemy course-of-action (COA) development detail how the enemy will potentially attack. They also provide an insight as to what and where the enemy's objective and routes might be. The SITEMP helps the engineer to understand how the enemy will traverse through the TF's sector and allows the engineer to gain an understanding of how and where he can best attack the enemy's maneuver.

The SITEMP also depicts how the enemy's reconnaissance forces will enter the sector. This is especially important when countering the enemy's ability to reconnoiter obstacle efforts.

The engineer must articulate the current capabilities of the engineer forces, its current combat power, and its ability to support the TF. Assumptions of future capability or potential reinforcement by other engineers should be analyzed. Specific characteristics of special engineer equipment and SCATMINE systems are detailed for the staff. An initial Class IV/V supply-point location and an operation plan should be developed with the TF staff (note that the TF has responsibility for Class IV/V supply-point operation). The XO/first sergeant (1SG) works with the TF and the engineer battalion Supply Officer (US Army) (S4) to ensure that delivery of Class IV/V barrier material supports the TF countermobility plan.

Analyze Relative Combat Power

The engineer compares friendly and enemy combat power and identifies possible obstacle requirements that offset potential enemy breaching and direct- and indirect-fire capabilities. The actual inclusion of the obstacles normally occurs after COA development. During this phase, the engineer finishes his EBA to gain an understanding for the engineer company's ability to support the TF.

Analyze the Engineer Battalion's/Brigade's Mission and the Commander's Intent

The staff analyzes and identifies information from the maneuver brigade order and the commander's intent that will potentially impact defensive planning. The engineer analyzes the maneuver brigade/engineer battalion commander's intent to determine potential obstacle placement, obstacle intent, and construction priority based on his concept of the operation.

The TF must identify tasks and limitations imposed from the brigade operation order (OPORD). These might include obstacle belts with or without specific intents, obstacle-restricted areas, or restrictions on the type of obstacles. Also, the brigade OPORD might specify reserve, situational, or directed obstacle groups.

The engineer must identify the TF's total obstacle capabilities. Available assets include engineer units, SCATMINE systems, and other units that can provide additional manpower for obstacle construction. Engineer-equipment status, work rates, and the time available must be evaluated in detail.

NOTE: Work rates should only be used in the absence of unit-developed planning factors.

Table 2-2 provides planning factors for the mine dump. Tables 2-3, 2-4, 2-5, and 2-6 provide planning factors for obstacles. Special focus to limited visibility work rates and engineer squad strengths must be made when making total-capability estimates. Plan to accomplish obstacle siting and Class IV/V supply-point setup during daylight hours, and plan to emplace mines during limited visibility hours as much as possible.

Table 2-2. Planning factors for the mine dump

Number of Personnel Quantity of Mines Required Equipment
2-man team (2 minutes per mine) 25 mines per hour Shears, metal cutting
Grease, automotive and artillery
Work gloves
Night-vision goggles
Squad (7 soldiers and an NCO) 100 mines per hour
Platoon (with leadership) 300 mines per hour; 3,600 mines per day
Company 10,800 mines per day
NOTE: Soldiers work 50 minutes per hour, 12 hours per day.

Table 2-3. Planning factors for work rates

Time Required to Construct
With D7F Dozer With ACE With SEE
Hull-defilade position 1 BTH 1.5 BTH NA
Turret-defilade position 2.5 BTH 3.5 BTH NA
HMMWV TOW position 1.5 BTH 2 BTH NA
Vehicle-protective position 0.75 BTH 1 BTH NA
Dismount-crew position NA NA 1 SEEH
Individual-fighting position NA NA 0.5 SEEH
With D7F Dozer With ACE In Man-Hours
Antitank ditch 1 BTH/70 m 1 BTH/50 m NA
Standardized disrupt minefield NA NA 1.5 PH
Standardized fix minefield NA NA 1.5 PH
Standardized turn minefield NA NA 3.5 PH
Standardized block minefield NA NA 5 PH
Triple-standard concertina NA NA 1 PH/300 m
Road crater NA NA 1.5 SH
Point minefield NA NA 1 SH
Concertina roadblock NA NA 1 SH
Bridge demolition (massive) NA NA 2 SH
Bridge demolition (steel) NA NA 1 SH
Mine preparation at the TF Class IV/V supply point NA NA 1 SH/100 mines

BTH (blade team hour). One blade team working for one hour. A blade team consists of two engineer blades (two dozers, two ACEs, or one ACE and one dozer). One vehicle digs (cutter) while the other spreads the spoil (striker). A dozer-ACE blade team uses the dozer BTH.

SEEH (SEE hour). One SEE working for one hour.

PH (platoon hour). One platoon (3 squads) working for one hour.

SH (squad hour). One squad working for one hour.

Table 2-4. Planning factors for standardized row minefields

AT Mines
AT Mines
Frag AP Mines
250 m
100 m
250 m
120 m
500 m
300 m
500 m
320 m
84 (Korea Only)

Table 2-5. Planning factors for scatterable minefields

Minefield Size
SD Time
Arming Time
ADAM 400 x 400 m
200 x 800 m
4 hr
48 hr
2 min 45 sec
RAAM 400 x 400 m
200 x 800 m
4 hr
48 hr
2 min 45 sec
Volcano (one load = 160
canisters or 960 mines
[800 AT and 160 AP])
Turn or block (1 per load):
  • Ground: 555 x 320 m
  • Air: 557 x 320 m

Fix or disrupt (4 per load):

  • Ground: 277 x 120 m
  • Air: 278 x 120 m
4 hr
5 days
15 days
2 min
MOPMS 70 x 35 m 4 hr* 2 min
Flipper Turn or block: 240 x 490 m
Disrupt or fix: 70 x 245 m
5 days
15 days
45 min
*Can be recycled 3 times for a total of 13 hr

Table 2-6. Ranges of common weapons

Effective Range
M16A2 580 m 400 m
M249 SAW 1,000 m 800 m
M60 1,100 m 1,100 m
M203 Area 350 m 350 m
Point 160 m 160 m
M2, .50 Cal Area 1,830 m 1,830 m
Point 1,200 m 1,200 m
MK19 Area 2,200 m 2,200 m
Point 1,600 m 1,600 m
AT4 300 m 300 m
M47 Dragon 1,000 m 800 m
Javelin 2,000 m 2,000 m
M1 Abrams tank 105 mm 2,500 m 2,000 m
120 mm 3,000 m 2,500 m
M2 Bradley ITV 25 mm (APDS) 3,000 m 1,700 m
25 mm (HEI-T) 3,000 m 1,700 m
TOW2 3,750 m 3,750 m
60-mm mortar HE 3,400 m 50 m (min)
WP 4,800 m 50 m (min)
ILLUM 931 m 50 m (min)
81-mm mortar HE 4,595 m 75 m (min)
WP 4,595 m 75 m (min)
ILLUM 3,150 m 75 m (min)
4.2-in mortar HE 6,840 m 770 m (min)
WP 5,650 m 920 m (min)
ILLUM 5,490 m 400 m (min)
BMP, 73 mm 800 m 800 m
AT3 missile 3,000 m 3,000 m
AT5 missile 4,000 m 4,000 m
BMP-2 2,000 m 2,000 m
BTR, 14.5 mm 2,000 m 1,000 m
T-72 tank, 125 mm 2,100 m 2,000 m
T-80 tank, 125 mm 2,400 m 2,000 m
T-80 AT8 4,000 m 4,000 m
*The planning range is based on ideal weather conditions during daylight.

Issue the Commander's Guidance

The commander should be as specific as possible with his initial obstacle guidance. If the commander narrows the COA focus, he should also provide obstacle guidance. His guidance is a key factor to an early start and must be solicited if not offered.

Course-of-Action Development

Detailed planning begins following the COA development (Figure 2-12). The engineer focuses on four specifics of obstacle planning in the scheme of engineer operations (SOEO) for the defensive plan:

  • Direct-/indirect-fire analysis.
  • Obstacle-intent integration.
  • Obstacle priority.
  • Mobility requirements.

Figure 2-12. TF defense COA

Direct-/Indirect-Fire Analysis

The direct-/indirect-fire analysis examines how engineers can best use obstacles (within the commander's intent) to enhance the direct-/indirect-fire plan. Figure 2-13 shows a sample direct-fire analysis. This analysis can be used to formulate obstacle locations with the direct-fire plan. The engineer must have a fundamental understanding of the direct-/indirect-fire and maneuver plans and the TF's organization of the EA to effectively integrate obstacles with the direct-/indirect-fire plan.

Figure 2-13. TF direct-fire analysis

Synchronization of direct and indirect fires with obstacles multiplies the relative effect on the enemy. An obstacle is an excellent location for preplanned artillery and mortar fires. These fires can eliminate dismounted breaching efforts. Indirect fires contribute to the threat's ability to breach, making the obstacle more effective and providing direct-fire systems a higher probability to kill.

Obstacle-Intent Integration

The engineer determines locations for the directed obstacle groups. Groups are placed on the COA overlay to support the maneuver plan. This location is for planning only and will normally be adjusted after the ground reconnaissance.

Obstacle groups target specific enemy elements based on the SITEMP. The engineer generally allocates an obstacle group against a battalion-size AA. This approach mirrors the staff's placement of a company/team against the same enemy force. The company's/team's fire responsibility drives the placement of the obstacle groups. The engineer advises the commander on which specific effect each directed obstacle group must achieve. He plans obstacle groups to--

  • Disrupt the enemy.
  • Turn the enemy into an area where friendly units can mass fires.
  • Fix the enemy in the EA and enhance his direct-fire destruction.
  • Block the enemy from using an AA.

The engineer integrates directed obstacle groups with the COA. The obstacle effects are shown on the COA overlay using obstacle-effect graphics (Figure 2-14). The engineer draws the obstacle-group graphic to reflect the location, the target, and the specific intent of the group as accurately as possible. The engineer should visualize how the terrain naturally effects maneuver. Terrain visualization is vital to proper obstacle-group design.

Figure 2-14. TF obstacle-intent integration and priorities

Note the placement and the effect of obstacle groups in Figure 2-14. First, the engineer must manipulate the MRB into the EA. The turn groups (2 and 5), combined with a heavy volume of AT fires from a company team at the turning point, achieves this. In the EA, particularly where the TF fires are massed, a fix group (3) slows the enemy and increases the effects of the fires. A block group (1) in the south, along with direct fires from a company team, will stop the advance of any element along the southern AA. A disrupt group (4), with indirect fires, will break up the C 2 and the tempo of the attacking force. Protective obstacles in front of all team positions protect the teams from the enemy's final assault.

Obstacle Priority

The staff determines the priority of each group depicted on the overlay. Priority is established by the commander's intent and the most likely enemy COA. The obstacle priority should reflect the TF's greatest obstacle requirement. The primary obstacle effort can be with an economy of force where the commander needs more obstacles to overcome a shortage of direct-fire systems. The TF engineer should be cognizant of flank protection, weapon types and ranges, and the overall commander's intent for the entire force before placing obstacle priority on the main EA. Priorities assist the engineer in allocating resources and ensuring that the most critical obstacle groups are emplaced first.

In Figure 2-14, the first priority is to turn the enemy where the fires are massed. The second priority is to deny the enemy access (block effect) to the southern AA. The fix effect is the third priority because it enhances the TF fires in the EA but only slows the enemy). The block effect is a higher priority than the fix effect because it stops the enemy from flanking the TF. The disrupt effect is the last priority.

Mobility Requirements

The engineer identifies the TF's mobility requirements. Obstacle groups should not be arrayed along potential counterattack routes or where there is a potential to hamper unit repositioning. Mobility assets should be used to counter potential enemy situational obstacles and friendly obstacles that might hinder friendly maneuver. The TF engineer must consider the commander's mobility requirements and plan for mobility assets so he can be ready when and where he is needed.

Course-of-Action Analysis

The staff war-games the COAs to determine their viability and recommends the best COA to the commander. The engineer refines the SOEO during this process as well. Obstacles should be considered within the context of the maneuver COA (Figure 2-15).

Figure 2-15. Obstacle-plan refinement

The engineer staff officer should consider the following:

  • Enemy reactions at the obstacle groups (breaching or bypassing capability) versus the desired obstacle effect.
  • Enemy breaching capabilities that make one obstacle type preferable to another (such as an AT ditch versus a minefield).
  • Obstacle locations that hinder friendly maneuver.
  • The compatibility of obstacle effects and weapon-system capabilities.
  • Adequate direct-/indirect-fire control measures and targeting that support the obstacle effect. The effects of artillery and obstacles must be synchronized to gain the desired effect on the enemy's maneuver.
  • Locations and types of enemy situational obstacles that make one type of breaching asset preferable to another.

After war gaming, the staff adjusts the COA (including the obstacle plan) by--

  • Changing the location of obstacle groups.
  • Changing the obstacle effects.
  • Adding more situational obstacles.
  • Adding more reserve obstacles.
  • Identifying other mobility requirements.
  • Refining artillery targets based on obstacle-group changes.

Mobility Requirements

The staff determines which obstacles require lanes and determines the closure criteria for the lanes. It also determines obstacle-restricted areas that support the TF's maneuver. Lanes and bypasses are determined using tactical repositioning requirements developed during the COA analysis. Requirements for rehearsal movement, placement of the target reference point (TRP), and logistical support of forward TF elements are also considered in lane development. Mobility requirements identified during COA development are synchronized and refined during COA analysis. Additional mobility requirements identified during war gaming are resourced and planned. (Lane marking is discussed later in this chapter.)

Obstacle Design/Resourcing

After the COA analysis, the engineer conducts a detailed study of the obstacle plan to determine resource requirements. Groups are resourced using the methods previously discussed. The TF engineer resources the obstacle groups based on their assigned priorities. Once the engineer has developed the resource requirements for the obstacle groups, he plans the individual obstacles within the group.

If time permits, a detailed ground reconnaissance of the obstacle-group location can be conducted. This will allow a more detailed analysis of the obstacle requirement for that AA, and then the engineer can plan individual obstacles. The TF engineer usually designates the intent to guide the companies/teams; the company/team commanders and their supporting engineers complete the actual design of the obstacle groups.

Decision and Execution

The engineer makes adjustments to the SOEO based on the COA that the commander approves. The engineer then provides oral, written, and/or graphical orders with sufficient detail to allow the subordinate units to conduct the operation. The engineer provides critical information using the scheme-of-obstacle overlay and the obstacle-execution matrix.

Scheme-of-Obstacle Overlay

The scheme-of-obstacle overlay (Figure 2-16) depicts the location of the TF's obstacle groups, brigade-directed obstacle groups (if any), and obstacle belts within the TF's sector. The overlay also includes any obstacle restrictions dictated from a higher headquarters. The overlay depicts the obstacle groups using the standardized obstacle-effect symbols. The overlay does not generally show individual obstacles unless the engineer has had sufficient time to conduct a thorough ground reconnaissance where exact obstacle locations have been identified. The engineer must exercise extreme caution if he uses individual obstacles on the overlay. He must ensure that inexperienced leaders do not attempt to emplace obstacles exactly as shown on the overlay, but instead, properly site the obstacle with the company/team commander. The scheme-of-obstacle overlay graphically depicts how the commander seeks to influence enemy maneuver through obstacles.

Figure 2-16. Scheme-of-obstacle overlay

Obstacle-Execution Matrix

The obstacle-execution matrix includes specific instructions and detailed information concerning the obstacle groups shown on the scheme-of-obstacle overlay. Develop an obstacle-execution matrix for all situational, reserve, and direct obstacles within the TF area. As a minimum, the matrix should include the information shown in Figure 2-17.

Figure 2-17. Sample obstacle-execution matrix

Continue Chapter 2

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