CHAPTER 6: OPFOR Defensive Operations

6-8 ENGINEER.

    a. Engineer support in the defense involves:

• Supporting the battle and transition to the offense

• Providing reconnaissance of the BLUFOR and terrain

• Repelling BLUFOR attacks in front of forward edge

• Repelling counterattacks or penetrations into defensive sector

• Supporting second-echelon counterattack

• Reinforcing lines taken in counterattack

    b. Engineer preparation. The OPFOR divides preparation of the defense into three stages. Obstacles, both natural and manmade, play an important role in the defense.

        (1) First Stage. Barbed wire and other obstacles are emplaced in front of the position and fields of view and fire are cleared. Pits or trenches are prepared at the primary position of each fighting vehicle, crew-served weapon, and individual infantryman. Command observation posts and medical posts are dug in. The OPFOR normally allows 5 to 6 hours for this work.

        (2) Second Stage. During the second stage of preparation of the position, fighting vehicles and weapons systems are provided with alternate fire positions. Trenches are linked until they run continuously across the battalion frontage. Communication trenches are prepared. The OPFOR allows an additional 5 to 6 hours for this phase.

        (3) Further Preparation. Further preparation of the position includes improvement of existing trenches and positions, laying further obstacles and preparation of firing lines and routes for antitank reserves and second echelons. Communication trenches may be improved for use as fighting trenches. Dummy positions are prepared in intervals between strongpoints.

    c. Minefields and obstacles. Defensive positions are supplemented with minefields and non-explosive obstacles such as antitank ditches and wire. Minefields are placed to channel BLUFOR armor into the kill zones, which can contain more mines, tank traps, and trenches. Obstacles are also placed to hold the BLUFOR in the fire sack. Ideally, these obstacles are placed at about 2/3 of the effective range of the systems that will be covering them. Minefield dimensions are typically configured 300 x 60 meters. Mine outlay can reach 1000 antitank or more per kilometer of frontage on major avenues of approach.

    Natural or manmade obstacles will be used to slow, canalize or disrupt the advancement of the BLUFOR. Excellent natural obstacles include lakes, rivers, marshes, ravines, densely forested areas and escarpments. The OPFOR may create additional manmade obstacles such as minefields, antitank ditches, wire entanglements and abatis to further hinder the attacking BLUFOR.

    The OPFOR will also use mines and obstacles to protect the flanks of its position. Typically, minefields and obstacles are covered with direct and indirect fires. The level of sophistication of the engineer preparation will depend on the time available and on the engineer resources of each OPFOR unit. Some examples of obstacle emplacement times are shown in Figure 6-9.

Figure 6-9. OPFOR Obstacle emplacement times.

    b. Engineer Reconnaissance. Engineer troops assist in reconnaissance and preparation of the defense by determining the protective and camouflage features of the terrain and aiding in selection of positions for command posts and strongpoints. Engineers determine road and bridge conditions in the defensive area, availability of local materials for construction of positions, and the status of the water supply. Engineer elements observe BLUFOR preparations for the attack and determine the character and extent of BLUFOR engineer activity. Emphasis is on observing BLUFOR engineer reconnaissance activity and obstacle-clearing elements, BLUFOR route preparation through or around obstacles, and the composition and character of BLUFOR engineer and maneuver elements in the forward areas.

    During actual defensive combat, engineer observation posts monitor BLUFOR engineer activity, evaluate zones of destruction, and report areas where the BLUFOR is breaching defensive obstacles. At least one of the posts provides detailed photography of the area of interest. The posts forward all information to the combined arms commander and the chief of engineer service. When the OPFOR forces are on the defensive, engineer reconnaissance elements continue to reconnoiter terrain and the BLUFOR situation to determine routes best suited for a return to offensive action.

    The reconnaissance patrol will not normally be given a mission to conduct defensive operations. On rare occasions where the reconnaissance patrol is involved in contact with a superior BLUFOR and cannot extract itself, it may have to take up a defensive position until assistance arrives or it can disengage itself. The reconnaissance patrol will move its vehicles into the best covered and concealed positions available, dismount the scouts, and defend itself against actual or possible BLUFOR, usually in a 360-degree defense.