(c) A force may initially be assigned battle positions on the forward edge of the town to provide early warning of the enemy's advance. The force engages the enemy at long range and deceives the enemy as to the true location of the defense. This force should withdraw in time to avoid decisive engagement. If there is limited observation from the forward edge, a force should be positioned on more favorable terrain forward or to the flanks of the town to gain better observation and to engage the enemy at long range.
(d) To prevent airmobile or airborne landings within the city or town, the commander must emplace obstacles on probable LZs and DZs, to include parks, stadiums, and large rooftops and heliports. Direct and indirect fires should also cover these.
(4)
Large Built-Up Areas. In large built-up areas, tall buildings are normally close together. This may require a higher density of troops and smaller defensive sectors than in other urban terrain. The density of buildings, rubble, and street patterns may dictate the depth and frontage of the unit (Table 6-1).
UNIT FRONTAGES
DEPTHS
SBCT infantry battalion
4 to 8 blocks
3 to 6 blocks
SBCT infantry company
2 to 4 blocks
2 to 3 blocks
SBCT infantry platoon
1 to 2 blocks
1 block
NOTE:
An average city block has a frontage of about 175 meters. These
minimum figures apply in areas of dense block-type construction,
multistory buildings, and underground passages.
Table 6-1. Approximate frontages and depths in large built-up areas.
(a) In a large built-up area, an SBCT infantry company has a sector, battle position(s), or a strongpoint to defend. Although mutual support between positions should be maintained, built-up terrain often allows for infiltration routes that the enemy may use to pass between positions. Therefore, the defender must identify the following:
• Positions that enable him to place effective direct fires on the infiltrating enemy.
• Covered and concealed routes for friendly elements to move between positions (subways and sewers).
• Structures that dominate large areas.
• Areas where antiarmor weapons have effective fields of fire, such as parks, boulevards, rivers, highways, and railroads.
• Firing positions for mortars.
• Command and control locations that offer cover, concealment, and ease of communications.
• Protected storage areas for supplies.
(b) Leaders choose buildings that add most to the general plan of defense for occupation. Mutual support between these positions is vital to prevent the attacker from maneuvering and outflanking the defensive position, making it untenable. Buildings chosen for occupation as defensive positions should have the following characteristics:
• Good protection.
• Strong floors to keep the structure from collapsing under the weight of debris.
• Thick walls.
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• Constructed of nonflammable materials (avoid wood).
• Strategically located (corner buildings or prominent structures).
• Adjacent to streets, alleys, vacant lots, and park sites. (These buildings usually provide better fields of fire and are more easily tied in with other buildings.)
• Covered by friendly fire and offering good escape routes.
(5)
Obstacles. A built-up area is itself an obstacle since it canalizes and impedes an attack. Likely avenues of approach should be blocked by obstacles and covered by fire (Figure 6-14). Barriers and obstacles should be emplaced in three belts, consistent with the ROE.
Figure 6-14. Example of urban obstacles.
(6)
Avenues of Approach. The defender must consider not only the conventional avenues of approach into and out of the city, but also the avenues above and below ground level within built-up areas. The defender normally has the advantage. He knows the built-up area and can move rapidly from position to position through buildings and underground passages. Control of these above- and below-ground avenues of approach becomes more critical when the defense of key terrain must be oriented against terrorism and sabotage. All avenues of approach (three-dimensionally) must be denied. SBCT
infantry company commanders must not overlook the use of field-expedient obstacles, such as cars and light poles, or the emplacement of command detonated antipersonnel mines and antitank mines. Commanders must clearly understand the ROE and what they are permitted to emplace. When necessary, obstacles can be emplaced without mines and covered by fire within the parameters of the ROE.
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(7)
Key Terrain. Key terrain is any place where seizure, retention, or control affords a marked advantage to either combatant. Examples of key terrain during UO are bridges over canals or rivers, building complexes, public utilities or services, and parks. The population of a built-up area may also be considered key terrain. The identification of key terrain allows the defender to select his defensive positions and assists in determining the enemy's objectives.
(8)
Observation and Fields of Fire. The defender must position weapons to obtain maximum effect and mutual supporting fire. This allows for long-range engagements out to the maximum effective ranges. Observers should be well above street level to adjust fires on the enemy at maximum range. Fires and FPFs should be preplanned and, if possible and ROE permitting, preregistered on the most likely approaches to allow for their rapid shifting to threatened areas.
(9) Cover and Concealment. The defender should prepare positions using the protective cover of walls, floors, and ceilings. Soldiers should always improve positions using materials on hand. When the defender must move, he can reduce his exposure by--
• Using prepared breaches through buildings.
• Moving through reconnoitered and marked subterranean systems.
• Using trenches.
• Using the concealment offered by smoke and darkness to cross open areas.
d.
Troops Available. Urban operations are manpower intensive.
(1)
Employment of Platoons and Organic Assets. Once the SBCT infantry commander has decided where to defend, he should select platoon battle positions or sectors that block or restrict the enemy's ability to maneuver and control key areas. The frontage for a platoon is about one to two city blocks long. Platoons can occupy about three small structures or a larger two- to three-story building (Figure 6-15). Along with his primary and alternate positions, the platoon leader normally selects one supplementary position to reorient his defense to meet enemy threats from another direction. Companies may be tasked to detach a platoon to act as the SBCT infantry battalion reserve.
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Figure 6-15. Platoon battle positions in a company sector.
(a)
Mortar Section. Mortars at the SBCT infantry company level are employed to maximize the effect of their high-angle fires. They should be used to engage--
• Enemy overwatch positions.
• Enemy infantry before they seize a foothold.
• Targets on rooftops.
• Enemy reinforcements within range.
(b)
Javelins. Based on the Javelin's capabilities and limitations, commanders give the platoons missions that can use antiarmor systems to support the defensive scheme of maneuver.
(2)
Employment of MGS Vehicles and ICVs. The SBCT infantry commander should employ MGS vehicles and ICVs to take advantage of their long-range fires, armored protection, and mobility. Some built-up areas may restrict the mobility of MGS vehicles and ICVs and make them vulnerable to enemy infantry antiarmor weapons.
(a) When MGSs and ICVs are employed in the defense of a built-up area, infantry should be positioned to provide security against close antiarmor fires and to detect targets for the armored vehicles. MGSs and ICVs should be assigned engagement areas in support of the defensive scheme of maneuver. ICVs and Javelins should supplement MGS fires. MGSs and ICVs may be--
• Positioned on the edge of the city in mutually supporting positions.
• Positioned on key terrain on the flanks of towns and villages.
• Used to cover barricades and obstacles by fire.
• Positioned as part of the reserve.
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(b) MGSs and ICVs are normally employed as a platoon. However, sections and individual vehicles may be employed with infantry platoons or squads. This provides MGSs and ICVs with the close security of the infantry. MGSs and ICVs provide the SBCT infantry company commander with a mobile force to respond quickly to enemy threats on different avenues of approach. They can also be effectively employed in counterattacks.
(3)
Employment of Fire Support. Fire planning must be comprehensive due to the proximity of buildings to targets, minimum range restrictions, repositioning requirements, and ROE. Mortar and artillery fires are planned on top of and immediately around defensive positions for close support.
(a)
Artillery. Artillery may be used as direct or indirect support. Artillery fire should be used--
• To suppress or obscure enemy overwatch elements.
• To disrupt or destroy an assault.
• To provide counterbattery fire.
• To support counterattacks.
• To provide direct fire when necessary.
(b)
Final Protective Fires. FPFs are planned to stop dismounted assaults in front of the defensive positions. Fires within the city are planned along likely routes of advance to destroy the enemy as he attempts to deepen a penetration.
(c)
Priorities of Fire. The SBCT infantry company commander should establish priorities of fire based on enemy avenues of approach and enemy systems that present the greatest danger to the defense. For example, during the attacker's initial advance, tanks, BMPs, and overwatching elements are the greatest threat to the defense. Javelins should concentrate on destroying armored vehicles. In certain situations, enemy armored personnel carriers (APCs) may present a larger threat than enemy tanks in a built-up area; the APCs carry infantry, which can gain footholds in buildings. Mortar and artillery fires should suppress enemy ATGMs and overwatch positions or elements. If enemy formations secure a foothold, priority shifts to the destruction of enemy forces within the penetration.
(d)
Control of Supporting Fires. As the attack progresses in the city, enemy indirect fires increase to separate infantry from supporting MGSs and ICVs. During this phase, friendly artillery concentrates on counterfire missions and the destruction of reinforcements that are approaching the city. Mortars concentrate on infantry attacks.
(e)
Support of Counterattacks. When initiated, counterattacks are given priority of supporting fires. When artillery fires the missions mentioned above, it must remain mobile and be prepared to displace to preplanned positions to avoid enemy counterbattery fire.
(f)
Indirect Fire Planning. At company and platoon level, indirect fire plans include fires of organic, attached, and supporting weapons. The SBCT infantry company commander also plans his own mortar and artillery fires on and immediately around his battle positions for close support.
(g)
Air Defense Assets. Air defense assets available to the commander, such as Stinger and Avenger, are normally employed to ensure all-round air defense. These assets are normally controlled at SBCT battalion level, but they may be placed under the SBCT
infantry company commander’s control when METT-TC factors warrant that type of use.
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The lack of good firing positions for long-range air defense missile systems in the built-up area may limit the number of deployed weapons. In the defense, weapons systems may have to be winched or airlifted into positions. Rooftops and parking garages are good firing positions because they normally offer a better line of sight. Stingers and Avengers may be assigned to protect specific positions or function in general support of the battalion.
(4)
Employment of Engineers. Engineers are employed under SBCT battalion control or attached to SBCT infantry companies. SBCT infantry company commanders may receive an engineer squad to assist them in preparing the defense. Commanders must consider engineer tasks that enhance survivability, mobility, and countermobility. Tasks that engineers can accomplish in the defense of a built-up area include--
• Constructing obstacles and rubbling.
• Clearing fields of fire.
• Laying mines.
• Preparing mobility routes between positions.
• Preparing fighting positions.
(5) Employment of the Reserve. The commander's defensive plan must always consider the employment of a reserve. The reserve force should be prepared to counterattack to regain key positions, to block enemy penetrations, to protect the flanks, or to assist by fire in the disengagement and withdrawal of positions. For combat in a built-up area, a reserve force--
• Normally consists of infantry.
• Must be as mobile as possible.
• May be supported by an MGS.
e. Time Available. The commander must organize and establish priorities of work, depending upon the time available. Many tasks can be accomplished simultaneously, but priorities for preparation should be in accordance with the commander's order. A sample priority of work sequence follows:
(1)
Establish Security. The unit should quickly establish all-round security by placing forces on likely avenues of approaches. METT-TC factors determine the level of security (for example, 50 percent or 30 percent). The reconnaissance and counterreconnaissance plan should be emphasized.
(2)
Assign Areas of Responsibility. Boundaries define sectors of responsibility. They include areas where units may fire and maneuver without interference or coordination with other units. Responsibility for primary avenues of approach should never be split. In areas of semidetached construction, where observation and movement are less restricted, boundaries should be established along alleys or streets to include both sides of a street in a single sector. Where buildings present a solid front along streets, boundaries may have to extend to one side of the street. Battle positions should also be specifically assigned to platoons, as required by METT-TC. The SBCT infantry company commander should specify which building(s) comprise the platoon battle position or strongpoint. Positions should be clearly designated so that no doubt remains as to which platoon has responsibility for occupation or control.
(3)
Clear Fields of Fire. In built-up areas, commanders may need to rubble certain buildings and structures to provide greater protection and fields of fire to the defender. If the ceiling of a lower-story room can support the weight of the rubble, collapsing the top
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floor of a building before the battle starts may afford better protection against indirect fires. Rubbling an entire building can increase the fields of fire and create an obstacle to enemy movement. Defenders must be careful, however. Rubbling buildings too soon or rubbling too many may give away exact locations and destroy cover from direct fire.
Planning must be extensive so that rubbled buildings will not interfere with planned routes of withdrawal or counterattack. Vehicles may also have to be moved to clear fields of fire.
(4)
Select and Prepare Initial Fighting Positions. The SBCT infantry company commander should select positions in depth. The unit should prepare positions as soon as troops arrive and continue preparing as long as positions are occupied. Enemy infiltration or movement sometimes occurs between and behind friendly positions. Therefore, each position must be organized for all-round defense. The defender should also--
(a) Make minimum changes to the outside appearance of buildings where positions are located.
(b) Screen or block windows and other openings to keep the enemy from seeing in or tossing in hand grenades. Include all windows so that the enemy cannot tell which openings the defenders are behind.
(c) Remove combustible material to limit the danger of fire. Fires are dangerous to defenders and create smoke that could conceal attacking troops. For these reasons, defenders should remove all flammable materials and stockpile firefighting equipment (such as water and sand). The danger of fire also influences the type of ammunition used in the defense. Do not use tracers or incendiary rounds extensively if threat of fire exists.
(d) Turn off electricity and gas at the facility that serves the urban area. Both propane and natural gas are explosive. Natural gas is also poisonous, displaces oxygen, and is not filtered by a protective mask. Propane gas, although not poisonous, is heavier than air. If it leaks into an enclosed area, it displaces the oxygen and causes suffocation.
(e) Locate positions so as not to establish a pattern. The unit should avoid obvious firing locations like church steeples.
(f)
Camouflage
positions.
(g) Reinforce positions with all materials available, such as mattresses, furniture, and so forth. Use caution because mattresses and fabric furniture are flammable. Fill drawers and cabinets with earth or sand to provide cover. Consider placing vehicles, such as trucks or buses, over positions outside buildings. Drain flammable fluids from vehicles and remove other flammables such as seats. Fill gas tanks with water.
(h) Block stairwells and doorways with wire or other material to prevent enemy movement. Create holes between floors and rooms to allow covered and concealed movement within a building.
(i) Prepare range cards, fire plans, and sector sketches.
(j) Consider how to use basements. If grazing fire can be achieved from basement windows, emplace machine guns in basements. When not using basements, seal them to prevent enemy entry.
(k) Cache resupply of ammunition, water, and medical supplies.
(5)
Establish Communications. When allocating time to establish communications, commanders should consider the effects of built-up areas. Line-of-sight limitations affect both visual and radio/digital communications. Wire laid at street level is easily damaged by rubble and vehicle traffic. The noise of built-up area combat is much louder than in 6-38
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other areas, making sound signals difficult to hear. Therefore, the time needed to establish an effective communications system in urban terrain may be greater than in other terrain. SBCT infantry company commanders should consider the following techniques when planning for communications:
(a) Emplace line of sight radios and retransmission sites on the upper floors of buildings.
(b) Use existing telephone systems. However, telephones are not secure even though many telephone cables are underground.
(c) Use messengers at all levels since they are the most secure means of communications.
(d) If assets are available, lay wire through buildings for maximum protection.
(6)
Emplace Obstacles and Mines. To save time and resources in preparing the defense, commanders must emphasize using all available materials (to include automobiles, railcars, and rubble) to create obstacles. Civilian construction equipment and materials must be located and inventoried. This equipment can be used with engineer assets or in place of damaged equipment. Coordination must be made with proper civilian officials before use, which is normally a brigade or battalion staff responsibility.
Engineers can provide advice and resources as to the employment of obstacles and mines.
(a) The principles for employing mines and obstacles do not change in the defense of a built-up area, but techniques do change. For example, concrete and asphalt make burying and concealing mines in streets difficult. Consider placing mines in sandbags so they are not visible and using fake mines placed in sandbags in order to deceive the enemy. Mines and obstacles must be emplaced consistent with the ROE. Any antipersonnel mines must be command detonated.
(b) Obstacles must be tied to buildings and rubbled areas to increase effectiveness and to canalize the enemy. Family of scatterable mines (FASCAM) may be effective on the outskirts of an urban area or in parks, but in a city core, areas may be too restrictive.
(c) Riot control agents may be employed to control noncombatant access into defensive areas.
(7)
Improve Fighting Positions. When time permits, all positions, to include supplementary and alternate positions, should be reinforced with sandbags and provided overhead cover. Attached engineers can help in this effort by providing advice and assisting with construction.
(8)
Establish and Mark Routes between Positions. Reconnaissance by all defending elements assists in route selection for use by defenders moving between positions.
Movement is crucial in fighting in built-up areas. Early selection and marking of routes adds to the defender's advantages.
f. Civilian Considerations. International law and moral imperatives require the SBCT infantry company commander to consider the effects of operations on the civilian population. The company commander must also consider cultural, economical, and political boundaries as they may have a direct impact on the range of tactical options available to him.
(1) Commanders may be precluded from countermobility operations directed at economically important roads, railways, and bridges. They must consider civilian movement when emplacing minefields. Commanders implement restrictive fire control measures consistent with ROE.
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(2) Units with large civilian populations in their AO often must conduct support operations while preparing a defense. When Army forces must damage areas that are important to civilians, they ensure that civilian leaders and populations understand why these actions are necessary.
g. Fire Hazards. The defender's detailed knowledge of the terrain permits him to avoid areas that are likely to be fire hazards. All urban areas are vulnerable to fire, especially those with many wooden buildings. The defender can deliberately set fires--
• To disrupt and disorganize the attackers.
• To canalize the attackers into more favorable engagement areas.
• To obscure the attacker's observation.
Likewise, the enemy may cause fires to confuse, disrupt, or constrain friendly forces and efforts. Company commanders should anticipate this possibility and ensure that firefighting equipment is on hand when conducting this type of operations.
6-14. COMMAND AND CONTROL
In all defensive situations, the SBCT infantry company commander should position himself well forward so that he can control the action. Regardless of the utility of FBCB2, the leader must see and feel the battlefield. In urban terrain, this is even more critical due to obstacles, poor visibility, difficulty in communication, and intense fighting.
a.
Graphic Control Measures. The use of graphic control measures and understanding of the commander’s intent two levels up by all leaders become even more important to mission accomplishment in an urban environment. Phase lines can be used to report the enemy’s location or to control the advance of counterattacking units.
Principal streets, rivers, and railroad lines are suitable phase lines. They should be clearly and uniformly marked on the near or far side of the street or open area. Checkpoints aid units in reporting locations and controlling movement. Contact points designate specific points where units make physical contact. Target reference points can facilitate fire control. These and other control measures ensure coordination throughout the chain of command.
b.
Command Posts. Command posts should be located underground, if possible.
Their vulnerability requires all-round security. Since each CP may have to secure itself, it should be near the reserve unit for added security. When collocated with another unit, however, CPs may not need to provide their own security. A simplified organization for command posts is required for ease of movement. Since rubble often hinders movement of tracked and wheeled vehicles, the company CP must be prepared to backpack communications and other needed equipment for operations. Alternate CP locations and routes to them must also be identified.
c.
Actions on Contact. When enemy forces enter and maneuver to seize initial objectives, the defender should employ all available fires to destroy and suppress the direct fire weapons that support the ground attack. Tanks and enemy APCs should be engaged as soon as they come within the effective range of antiarmor weapons. As the enemy attack develops, the actions of small-unit leaders assume increased importance.
Squad and platoon leaders are often responsible for fighting independent battles. Thus, it is important