Infantry Drills

3-120: Tactical Obstacles

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3-120. The company commander assigns obstacle groups, and tells the platoon leaders and engineers what he wants to do to the enemy, and then he resources the groups accordingly. Obstacle intent includes these elements:

  • The target, which is the enemy force that the commander wants to affect with fires and tactical obstacles. The commander identifies the target’s size, type, echelon, avenues of approach, or any combination of these.
  • The obstacle effect describes how the commander wants to attack enemy maneuver with obstacles and fires. Tactical obstacles block, turn, fix, or disrupt. Obstacle effect integrates the obstacles with direct and indirect fires.
  • The relative location is where the commander wants the obstacle effect to occur against the targeted enemy force. The commander initiates the obstacle integration process after identifying where on the terrain the obstacle will most decisively affect the enemy.
  • For example, the company commander might say, “Deny the enemy access to our flank by turning the northern, mechanized Infantry battalion into our engagement area. Allow companies B and C to mass their fires to destroy the enemy.” Scatterable minefield systems and submunitions are the main means of constructing tactical obstacles. These systems, with their self- and command-destructcapabilities, are flexible, and they aid in rapid transitions between offensive and defensive tasks. They do this better than other constructed obstacles. The force constructs conventional minefields and obstacles only for a deliberate, long-term defense. In those cases, the company and platoons usually are augmented with assets from a divisional engineer battalion. Table 3-2 shows the symbols for each obstacle effect, and it describes the purpose and characteristics of each.
Table 3-2. Obstacle effects

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Go Back To: U.S. Army FM 3-21.8: The Infantry Rifle Platoon and Squad