The engineer estimate is an extension of the military decision-making process (see FMs 5-100, 5-71-3, 71-2, and 90-7). It is a logical thought process conducted by the engineer concurrently with the supported maneuver force's tactical planning process. The engineer-estimate process generates early integration of the engineer plan into the combined-arms planning process. It drives the coordination between the engineer, the supported commander, and other staff officers and the development of detailed engineer plans, orders, and annexes.
Each step of the engineer-estimate process corresponds to a step of the decision-making process. Like the decision-making process, the engineer estimate is continuously refined. Table A-1 shows the relationship between these two processes. A more detailed discussion of each step of the engineer-estimate process is found below.
Analyze the conclusions on the terrain's impact on accomplishing the
Consider the enemy's mission and doctrinal employment of engineers
Consider the friendly mission.
Estimate the engineer assets available based on task organization
Estimate the total engineer capability based on engineer planning factors.
To analyze the terrain and the enemy, the engineer commander uses the IPB and the EBA. The engineer XO uses the same process to assist in developing the TF's SITEMP and the engineer estimate. The IPB is a tool used to see the terrain and the enemy. The first two steps of the EBA do the same, but with an engineer focus. For example, the EBA will detail how the enemy engineers will modify terrain and develop EAs. This is critical information needed to complete the TF's SITEMP. However, the IPB process is used by the engineer to develop his "engineer-specific" IPB. The IPB is only two-thirds of the EBA process. The friendly engineer capability must be analyzed to complete the EBA. The TF engineer must use all assets and resources available-the TF S2, the brigade engineer, and the engineer battalion staff-during the IPB/EBA process.
The EBA is a continuous process that is continually refined as the situation becomes clearer. Each time new information is collected or the conditions change, the engineer must evaluate its impact on the mission and refine the facts and assumptions as necessary.
To do a proper EBA, the engineer company planner must understand the IPB process. The following paragraphs detail the IPB process and the engineer contribution to the completed product. For more information on the IPB, see FM 34-130.
Specifically, weather analysis determines the effect of the weather on the mission. Weather affects terrain, equipment, visibility, and soldiers. Snow, dust, humidity, and temperature extremes all have an impact on soldier efficiency and limit the potential of weapons and equipment. Poor visibility affects obstacle placement. Normally, inclement weather will favor an attacker but will degrade his mobility and C2. Defenders are less likely to be alert and weapons less effective. The attacker can close with the defender with greater ease in limited visibility conditions. Table A-3 summarizes the effects of weather.
Soldiers and equipment
Soldiers, trafficability, and equipment
Observation and obstacle placement
Observation and obstacle construction rate
Terrain analysis is a major component of the IPB. The objective of the terrain analysis is to determine the impact that the terrain (including weather) will have on mission accomplishment. The engineer supports the intelligence officer in this process. Using the OCOKA framework (see Table A-4), the engineer determines what advantages or disadvantages the terrain and anticipated weather offer to both enemy and friendly forces. This process has a direct impact on planning engineer operations. Table A-4 shows examples of how the components of OCOKA may impact engineer support.
Observation and Fields of Fire. Terrain and vegetation affect the friendly and enemy forces' capabilities to observe one another and engage each other with direct-fire weapons. Dead space is normally covered by indirect fire or sensors. Observation and fields of fire are used to identify potential EAs, defensible terrain, and specific system positions and to identify where maneuvering forces are most vulnerable to observation and fires.
In the defense, a potential mission for the engineer company is to improve fields of fire by cutting down trees, power lines, and vegetation. Intervisibility and unobstructed view from one point to another are other factors of observation and fields of fire. The analysis of both are critical to obstacle siting.
Cover and Concealment. Cover is protection from enemy fire. Concealment is protection from enemy observation. Both describe the viability of key terrain and the AA. Advances in technology, such as thermal sights, have affected the availability of concealment. The evaluation of concealment and cover aids in identifying defensible terrain, possible approach routes for breaching, assembly areas, and deployment and dispersal areas.
Obstacles. Obstacles are classified as both existing and reinforcing. Existing obstacles are further broken down into natural and cultural classes. Reinforcing obstacles include tactical and protective obstacles emplaced by soldiers to multiply combat power through terrain reinforcement.
The obstacles analyzed during the IPB/EBA process include both existing and reinforcing, but focus on existing obstacles. However, any reinforcing obstacles in the battlefield environment are included in the analysis. Obstacles define the AAs. They create cross compartments in the AA and can turn, fix, block, or disrupt maneuver. The following are examples of natural obstacles:
Unrestricted terrain is fairly open and presents no hinderance to ground movement. Nothing needs to be done to enhance the force's mobility. Unrestricted terrain is a function of the type of unit moving on the terrain. Table A-5 depicts the terrain that is considered to be unrestricted (favorable).
Restricted terrain hinders ground movement. Little effort is needed to enhance mobility. Restricted terrain is also a function of the type of unit traversing the terrain. Table A-6, depicts terrain that is considered to be restricted and Table A-7 depicts terrain that is considered to be severely restricted (unfavorable).
Key Terrain. Key terrain is any locality or area that affords a marked advantage to whichever combatant seizes, retains, or controls it. It is not necessarily the highest hill in the area. It could be a piece of high ground where a force can overlook low ground, a major road junction, or even a river or stream crossing site. Key terrain can be controlled by fire, obstacles, or the relative positioning of friendly forces. It is often selected for battle positions or objectives. Some examples of key terrain are-
Mobility corridors are areas within AAs that permit movement and maneuver. These are mostly open areas with good routes for rapid movement and mutual support. When existing or tactical obstacles cross an AA, they form lines of resistance called cross compartments. Table A-8 depicts the frontages that determine the size of the unit that can deploy along each mobility corridor.
Engineer threat evaluation should provide the TF S2 with the number of obstacles that the enemy can build (by type), the amount of fortification he is capable of, and how many breaches the enemy can complete given his equipment and doctrine. The engineer must ensure that these analyses are incorporated into the TF's SITEMP.
Threat analysis and integration are also major components of the IPB. Enemy mission and engineer capability are subcomponents of the threat-analysis and -integration process. The engineer supports the intelligence officer during the threat evaluation by focusing on the enemy's mission as it relates to enemy engineer capability. When executing this component of the EBA, the engineer must first understand the enemy's anticipated mission (attack or defend) and consider how enemy engineers will be doctrinally employed. He then develops an estimate of the enemy engineer capabilities. To do this, he uses the S2's order of battle and knowledge of enemy engineer organizations and other assets (such as combat vehicle self-entrenching capabilities) that may impact engineer operations. The engineer must also consider confirmed intelligence pertaining to recent enemy engineer activities.
The engineer then uses the S2's SITEMP and the enemy-capability estimate to plot the enemy's engineer effort and its location. Coordinating with the S2, the engineer recommends PIR and the engineer force necessary to augment the reconnaissance effort. Enemy engineer activities must be organic to the total combined-arms R&S plan. Table A-2 contains a quick summary on enemy mission and engineer-capability analysis.
In the defense, the engineer plots the-
The third component of the EBA estimates the friendly engineer capability and its impact on mission accomplishment. To perform this function, the engineer uses the information he developed in the first step of the engineer estimate (receive the mission).
Knowing the type of operation, the engineer quickly prioritizes the development of capability estimates. He considers engineer forces task-organized to his supported unit as well as the assets that other members of the combined-arms team have (such as mine plows) to determine the assets that are available. Assets under the control of the higher engineer headquarters and adjacent engineer units should be noted for future reference in the event a lack of assets is identified during SOEO development.
Having determined the assets available and having already estimated and refined the time available with the S3, the engineer uses standard planning factors or known unit work rates to determine the total engineer capability. For example, in the offense, the engineer would focus first on the amount of breaching equipment (AVLBs, MICLICs, ACEs, engineer platoons, and CEVs) available and translate that into breaching lanes. In the defense, the engineer would determine the number of minefields, hull- or turret- defilade positions, and tank ditches that he could construct with available resources. He uses the results of his capability estimates during the SOEO development. Table A-2 contains an outline of this analysis.
The engineer combines his analyses of the terrain, enemy capability, and friendly capability to form facts and assumptions about the following:
The availability of key breaching equipment such as the ACE, the CEV, the AVLB, and the M1A1 plows and rollers, are tracked to keep the TF commander apprised of the breaching capability available. During the war-gaming phase of the tactical decision-making process, the engineer normally recommends the placement of TF breaching assets as well as the breaching technique based on the terrain and enemy obstacle threat. He also determines the number of lanes the TF potentially can make. Table A-9 shows the TF's breaching capability.
Likewise, the engineers provide the TF commander with details of the friendly capability to build fortifications and obstacles. Generally, this is done by meters of minefield or the number of obstacles and the number of fighting positions potentially available. These estimates are functions of time, equipment, troops, soil conditions, the unit training level and materials available. Table A-10 shows the engineer company's capabilities to create obstacles as well as planning factors for obstacle construction. Table A-11 shows the planning factors for fortification (for comparison, all equipment is available). This table uses the following planning factors:
Identify engineer missions and allocate forces/assets.
Develop an SOEO.
Balance assets available with support requirements.
Integrate into the maneuver COA.