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Chapter 1


This chapter focuses upon a modern battlefield against an enemy using Soviet style tactics and organizations. It discusses the modern battlefield, emphasizes threat operational concepts, particularly threat engineers and their capability to provide countermine and counterobstacle support to the offense, and covers the importance of friendly countermobility activities to deny the threat freedom of movement.






The most dangerous threat to United States' (US) national interests will most likely involve highly trained enemy forces using Soviet style tactics, organizations, and equipment. The actual battle will be intense, fast, and deadly. United States forces must therefore be prepared and trained to fight on a future battlefield where--

  • Highly mobile forces will use combat systems delivering firepower of unprecedented volume, speed, accuracy, range, and lethality.
  • Airspace will be crowded with aerial combat, surveillance, transport, reconnaissance, and target acquisition systems.
  • Communications systems will be the target of indirect fire and sophisticated electronic warfare operations, making command and control difficult to achieve and maintain.
  • Scatterable mine systems will severely affect ground mobility due to rapid and remote delivery means.
  • Employment of nuclear, biological, and chemical (NBC) weapons will create anew experience and add new dimensions to the environmental conditions.

Ultimate success on the battlefield will depend on mobility and countermobility efforts, not only near the forward line of own troops (FLOT), but also in rear areas. Successful commanders will need to concentrate forces at the decisive time and place, make maximum use of unit versatility, exercise movement and maneuver, impede the opposing force's movement and maneuver, and preclude enemy reinforcement of committed units and their resupply.


Engineers play a vital role in the success of threat army combined arms operations. In the threat view, the greater the increase in mobile warfare, the greater the need for passable terrain. Therefore, stated in simple terms, the mission of the threat combat engineers is to keep the offense moving. Threat engineers are organized, equipped, and trained to accomplish this mission under fire and in all environments including NBC.


All tank and motorized rifle units down through the regimental level have organic engineer elements. In combat, these elements form special engineer combat groups--either under control of parent command or attached to subordinate commands--to perform direct support missions. Engineer elements are also combined with other branch elements in operational groupings to perform specific tasks. At higher echelons (Front or Combined Arms Army), considerable engineer reserves are maintained either for concentrated use as needed, or for attachment to subordinate formations. This reserve allows rapid switching of engineer effort from one area to another, affording maximum tactical and operational flexibility. Furthermore, it is not unusual for the senior formation commander to strip a unit of its engineer element when that element is required for a concentrated effort elsewhere on the battlefield.

Doctrine emphasizes that commanders at all levels must strive for maximum flexibility in using engineer assets, inasmuch as engineer tasks are not isolated but are part of the overall tactical plan.

Combat engineer units at any level are of two general types: engineer special/technical units or general purpose engineer units.

Special/technical units perform the following tasks:

  • Engineer reconnaissance.
  • Road and route preparation.
  • Field fortification construction.
  • Bridge construction.
  • Camouflage.
  • Assault river crossing.
  • Obstacle construction and/or removal.
  • Minefield breaching and clearing.
  • Water supply.

General purpose engineers may perform any or several of the above tasks, but usually to a lesser degree than their special/technical counterparts. In either case, the threat envisions that most if not all of these tasks are conducted under fire or well in advance of main assault elements.

Technical repair of pipelines and topographic surveying are not the responsibility of threat engineer units. In addition, many simple and general engineer tasks are not carried out by engineer soldiers, but by soldiers of other combat arms. For example, all threat combat soldiers are expected to be proficient at mine clearance. The operation of tank-mounted mine plows and rollers is a responsibility of armored forces, although engineer advice is available in deciding whether to employ such devices.

The organization of threat engineer units is the result of careful study and is designed to accomplish specific objectives. These objectives are:

  • Conducting engineer tasks necessary to support the tactical employment of other combat arms, especially the movement of tank and motorized rifle elements.
  • Attaching additional engineer assets to subordinate elements and maintaining a significant engineer reserve.
  • Dovetailing and expanding engineer tasks in the offense by follow-on engineer elements of increased capabilities.
  • Providing cohesion to the defense and security in the offense by employing mines, obstacles, field fortifications, and antitank defenses.

The structure of engineer units is constant at the regimental and divisional levels, but not at higher levels of command. The engineer units assigned to a Front or Combined Arms Army will vary with the level of importance of the major command in the overall operational or strategic plan. Generally, a Front engineer reserve is likely to be twice as large as that of a Combined Arms Army.


Threat military principles are observed in order of precedence. To a certain extent, threat military principles appear as rephrasing of Western principles of war. However, applying these principles is peculiar to threat military theory, and threat units are configured and equipped to attain them. These eight military principles, in order of priority, are:

1 Mobility and high rates of combat operations.

2 Concentration of main efforts and creation of superiority in forces and means over the enemy at the decisive time and place.

3 Surprise and security.

4 Combat activeness (constant combat and pressure).

5 Preservation of the combat effectiveness of friendly forces.

6 Conformity to the goal.

7 Coordination.

8 Action upon the enemy to the entire depths of his employment and deep into his rear area.

These principles are basic to a threat officer's approach to any combat problem, and will have a profound effect on any decision made. For example, achievement of high speed in the execution of combat missions is the first principle, and will therefore take precedence over the need to avoid casualties and preserve the combat effectiveness of friendly troops. In other words, saving time is more important than saving lives, since fewer lives would be lost if the threat commander is allowed to exercise battlefield initiative and dictate the terms of combat. While adhering to these principles, the role of combat engineers is to assist other elements of combat arms to follow them more closely, thereby attaining greater combat effectiveness.

The threat has certain principles peculiar to combat engineers. These principles are binding upon the engineer commander and state that combat engineer operations must--

  • Correspond to the impending battle concept and support the commander's plan.
  • Be completed in time to allow the completion of tactical activities necessary in implementing the plan.
  • Be concealed to deprive the enemy of intelligence indicators.
  • Contribute directly to the effect of the main attack in the offense or the main sector in the defense.
  • Be capable of rapid maneuver to adapt to changing battlefield situations.
  • Deceive the enemy regarding the direction or location of the main effort.


In the offense, the chief function of engineers is to assist in maintaining high rates of movement, which is the premier tactical principle of threat military doctrine. Emphasis is placed on clearing and maintaining routes for the advance of combined arms units, to include breaching or removing mines and obstacles, crossing water obstacles, and assisting in flank protection or protection against counterattack. Engineer reconnaissance, independently or in collaboration with other reconnaissance means, plays a significant role in facilitating movement. Camouflage and protection during halts or temporary assumption of the defense are also basic engineer functions.

Secondary attention is given to supporting logistic operations in rear areas. The practical effect of these engineer requirements is to create certain key functions which must be satisfied by engineer troops. These functions include:

  • Engineer reconnaissance.
  • Movement support.
  • Mine and countermine warfare.
  • Wet and dry gap crossings.

Engineer reconnaissance

The goal of engineer reconnaissance is to provide a comprehensive report on the passability of march routes. Engineer reconnaissance is conducted by engineer elements attached to combined arms or reconnaissance units, or by engineer officers acting as part of the commander's reconnaissance party which checks the validity of plans made from intelligence without actual prior inspection of the terrain. Engineer elements performing this reconnaissance must determine--

  • The degree of passability of the entire route.
  • The location and nature of obstacles to be overcome and the engineer assets required to overcome them.
  • The condition of all crossing sites, wet or dry.
  • The location and quantity of material which can be used to improve the march route.
  • The nature of the terrain and location of areas with natural concealment.

In the conduct of engineer reconnaissance, the most commonly employed formation is the Soviet engineer reconnaissance patrol, Inzhenerny Razvedyvatel'ny Dozer (IRD). The IRD may vary in strength from a squad to a platoon. Commanded by an officer or senior noncommissioned officer (NCO), it is equipped with the necessary equipment for accomplishing its task. The IRD will almost always be vehicle-mounted, utilizing the reconnaissance version of the BRDM or BTR60. The commander is issued maps and aerial photographs of the march route and provided with the column composition indicating the number and types of vehicles the route must accommodate.

Significance to Friendly Forces

The appearance of engineer reconnaissance elements serves as an important intelligence indicator of impending offensive action. In addition, since engineer reconnaissance is normally conducted one to one-and-a-half days in advance of the main force's movement, it provides highly valuable information regarding the timing of threat activity. Since threat offensive tactics are predicated upon high rates of movement and engineers are paramount in implementing this movement, friendly counterreconnaissance action directed against IRDs will deprive the threat commander of engineer intelligence vital to executing the tactical plan. Finally, the documents carried by the IRD commander provide portions of the threat commander's actual tactical plan.

When in close proximity to enemy forces occupying prepared defensive positions, threat engineer reconnaissance will be conducted in a different manner than when it supports an approach march. In such an instance, existing intelligence concerning roads, topography, defenses, and the like, will be initially supplemented by aerial photography and aerial visual reconnaissance. Engineers will be attached to many combined arms reconnaissance elements. The IRDs will be employed to penetrate defenses to reconnoiter either a specific avenue of approach or particular defensive fortifications and obstacles. Additionally, reconnaissance may be conducted by establishing covert engineer observation posts close to, or actually within, the defensive sector.

One engineer observation post (OP) is normally established per 2 kilometers of front in order to observe the entire enemy FLOT and ascertain the engineer action and equipment necessary to properly support the attack. As the attack progresses, these OPs continue to observe the effectiveness of the engineer assault and make recommendations concerning alteration of the operation plan or commitment of the engineer reserve. The purpose of engineer reconnaissance is to develop intelligence supporting the employment of first echelon assault elements. The value of denying engineer information through aggressive counterreconnaissance cannot be overemphasized. Since assault engineer tasks are a prerequisite to the execution of the threat commander's tactical plan, any friendly action which interferes with these tasks will concurrently degrade the execution of the plan.

Movement support

The threat army believes that, without adequate engineer preparation, the approach march is sometimes not possible at all. Therefore, the results of engineer reconnaissance serve two purposes:

1 Selecting column routes which require the least engineer preparation.

2 Planning the employment of engineer assets for any route clearing needed.

Principles of movement

Considering the results of engineer reconnaissance and the tactical requirements of the operation plan, the commander selects the unit's approach route. The Chief of Engineer Services then drafts the engineer plan for movement support. This plan is based upon two principles:

1 Engineer soldiers must be equitably dispersed throughout the march column to insure proper engineer support to the entire formation.

2 Engineer soldiers must work as far in advance as possible.

Threat doctrinal texts state that movement support elements should ideally operate one-half day in advance of the main force. The manual task of route preparation usually falls to a temporary organization called a movement support detachment, Otriad Obespecheniya Dvizheniya (OOD). Several OODs can be formed from the engineer battalion of the tank and motorized rifle division, while additional OOD assets exist in the engineer companies of the tank and motorized rifle regiments.

Responsibilities of the OODs

Specific responsibilities include the following:

  • Clearing and leveling areas of movement.
  • Building approaches and exits at streams, ravines, or other obstacles.
  • Constructing bypasses.
  • Breaching and clearing mines.
  • Marking routes.

The organization of the OOD may vary depending on the scale of work undertaken and the assets available. In general, the faster the desired rate of advance, the stronger the OOD. In most if not all cases, the OOD will be reinforced with tank and motorized rifle elements to assist engineers in those tasks conducted under fire. Typical variations in the structure of OODs are shown in the following illustration. The groups are organized having the following missions:

  • Reconnaissance and Barricade Destruction Group: Reconnoiters march route, clears obstructions, and selects column route.
  • Road and Bridge Group: Prepares route and provides crossings.
  • Route Marking Group: Marks route and provides security and traffic control

Moving into position directly behind the division's advanced guard, or sometime behind the advanced guard's point security patrol, the OOD normally moves about 1 to 2 hours in advance of the head of the march formation. A typical sequence of activities for an OOD would consist of:

  • The reconnaissance and barricade destruction group reconnoiters enemy minefield and obstacles protecting a river crossing. Obstacles are cleared by engineers using explosives, while plow and roller-equipped tanks clear lanes. through the minefield. Using information previously obtained by an IRD, additional reconnaissance of the river banks is conducted to determine the exact extent of preparation necessary for bridging. Enemy troops in the area are engaged by tank and motorized rifle elements.
  • Road and bridge groups improve initial lanes through minefield, prepare banks for bridging equipment, and emplace bridges.
  • As preceding groups continue movement, the route marking group emplaces required route and bridge markers, establishes traffic control points, and regulates traffic flow until relieved by military police traffic units.
  • The threat uses smoke and supporting indirect fire as necessary to assist the OOD in accomplishing required tasks.

Threat doctrine for route preparation stipulates that, as an average, a divisional engineer battalion should be able to prepare up to 100 kilometers of route per day in open country where roads or tracks have not been subjected to specific enemy action to block or destroy them. If the route has been specifically interdicted by the enemy, then only 20 to 40 kilometers per day can be achieved, less if the engineer tasks must be conducted under fire, In such cases, it is common for threat engineers to construct a rough track parallel to the planned route, if possible, in order to maintain the tempo of the advance.

Significance to Friendly Forces

Threat offensive operations are predicated upon high speed execution and the sequenced arrival and departure of combined arms teams at specific locations at designated times. Thus, dependent upon an exceptionally high degree of coordination, the threat commander relies to a critical extent upon the movement support activities of his engineer troops. Action which denies the accomplishment of engineer route preparation activities may create a potentially disastrous situation for the threat commander. The delay of an advancing column by an unexpected obstacle not only disrupts coordination and slows the tempo of battle, but also causes succeeding units to combine with those in front, creating a highly rewarding target for friendly fires.

Mine and countermine warfare

In the threat view, the most important features of mines are speed and ease of emplacement on the battlefield. Emplacing a mine belt is considered much more effective and efficient against infantry and tanks than trenches, wire, or other fortifications. Mines are a much quicker means of erecting a defense. Consequently, they are widely used even in offensive operations. In supporting the offense, engineers employ extensive minefield in several situations such as--

  • When temporarily assuming the defense.
  • When protecting against counterattack.
  • When providing flank protection.

In any future war, the threat believes there will be no distinct front line nor a clearly defined forward edge of the battle area (FEBA) or FLOT. Rather, there will be a series of offensive and counteroffensive axes in the form of spurs and salients. Given the fluidity of combat under such conditions, a mine obstacle offers far greater flexibility in employment than antitank ditches, tetrahedrons, and other such relatively static obstacles. Minefield will be the most common means of protecting vulnerable aspects of offensive deployment, and mined areas may be expected to be far greater than those encountered in World War II. Although all threat troops are trained in the fundamentals of mine warfare, combat engineers are specially trained to perform this function. The primary combat engineer element performing mine warfare support for the offense is a temporary organization called a mobile obstacle detachment, Podvizhnoy Otriad Zagrazhdeniya (POZ), which is formed from elements of regimental and divisional combat engineers.

In the offense, POZs are positioned on the flanks of the march column, and usually are closely associated with the antitank reserve. Each POZ will be equipped with up to three PMR-3/60 minelaying trailers with towed mine-carrying vehicles, or the newer GMZ tracked armored mine-laying vehicle which is rapidly replacing the older PMR-3/60. In certain instances, the Mi-8/HIP helicopter with removable mine racks and chute dispensers may be used to emplace mines from an altitude of about 5 meters. A divisional POZ equipped with the GMZ tractor is capable of emplacing a 1,000-meter minefield containing 750 to 1,000 mines at 4-or 5.5-meter intervals within 30 minutes on suitable ground.

Temporary assumption of the defensive

If the attack fails, engineers must be prepared to conduct rapid fortification and obstacle activity in support of the hasty defense. In this role, POZs will perform as they do in offensive combat and emplace mines in accordance with the overall defensive plan.

Protection against counterattack

In planning the offensive employment of the command, the threat commander constantly evaluates the battlefield for suitable enemy counterattack areas. Areas identified as favorable are usually those which would detract from the maneuver of the combined arms teams, and be considered vital for mine employment in order to deny the enemy commander tactical initiative.

Flank protection

Engaging in a battle of dispersion and maneuver necessarily creates extensive exposed flanks. In threat theory, preventing enemy exploitation of such a condition relies, on two actions: rapid execution of combat tasks before the enemy can react, and protection of flanks by extensive minefield. During the march to contact and during the engagement itself, POZs actively emplace mines on the flanks of maneuvering units to preclude being attacked by mobile forces of the enemy.

In the late 1960s and early 1970s, the tendency for a POZ to create an obstacle by alternating minefield with other antitank obstacles along a 6- to 7-kilometer front is now considered ineffective, as is the practice of laying long strip minefield without covering them by antitank fire. Current threat teaching stresses the need for anititank guns to engage tanks as soon as they encounter the minefield. Thus, a short, deep mine and gun obstacle belt is preferred to a long, thin one, making choice of position critical.

Because of the possible need to recover minefield as the advance progresses, antipersonnel mines are rarely included in an antitank minefield laid in support of offensive operations. Minefields left behind are clearly marked and recorded, and their locations are reported to the Chief of Engineer Services.

Significance to Friendly Forces

In the offense, the commander employs mines in areas evaluated as offering the enemy a significant advantage to interfere with the tactical plan. Thus, the detection of minelaying activity offers the friendly force an indication of the manner in which the threat command will be employed, and highlights those areas deemed critical to success.

The threat, in planning for the widespread employment of mines, fully expects any enemy to engage in extensive mine warfare. Consequently, countermine warfare is an extremely important task entrusted to combat engineers. Breaching lanes through enemy minefield is critical to the goal of keeping the attack moving. Equally important is the desirability of conducting mine breaching operations covertly, whenever possible, to preserve surprise. When attacking from the march, the location of enemy minefield is the responsibility of engineer reconnaissance patrols (IRDs). The IRD is equipped with several types of mine detectors, the most common being the DIM metallic mine detector mounted on the UAZ 69, 1/4-ton, 4 x 4 Light Utility Vehicle. The DIM is synchronized with the vehicle's ignition system and, upon detecting a metallic mine, cuts out the electrical system and kills the engine. The IRD reconnoiters the limits of the minefield and marks it for the following movement support detachment (OOD).

In breaching the required number of lanes through the minefield, the OOD will employ several types of mine breaching equipment. The normal threat method of breaching minefield during an assault or rapid advance is to employ mine plows fitted to the lead tanks. Although engineers will reconnoiter the minefield, the initial breaching is not primarily an engineer task. The KMT-4 and KMT-6 plows are normally employed on the scale of one per platoon of three to four tanks. Engineers assist in fitting these and plow-roller combinations (KMT-5s) commonly used for minefield reconnaissance. The threat estimates clearing speeds of about 6 kilometers per hour (kph) for plow-fitted tanks, and about 10 kph for roller-fitted tanks. Combat vehicles follow these plow-equipped tanks in the breaching of a minefield. The threat employs a mine-clearing device mounted on the BTR-50 PK Armored Personnel Carrier (APC) (two to each divisional engineer battalion). This device fires and then detonates an explosive hose (line charge) across the minefield. It clears a lane about 180 meters long by 6 to 8 meters wide. This equipment is particularly useful during an assault river crossing when there are minefield on the far bank and amphibious vehicles may have to initially operate in the bridgehead without tank support.

Another mine-clearing device is the explosive line charge. It consists of three separate linear charges, a nose section, and a detonator box. Each linear charge may be assembled to any desired length by connecting 2-meter sections together with threaded collars. The light, sheet metal, 5-centimeter-diameter, tubular sections are filled with cast trinitrotoluene (TNT) explosive at 9 kilograms per linear meter. This device is versatile in that it may be used as a single, double, or triple charge. The forward end section is fitted with a roller to facilitate insertion of the charge into a minefield. The device is assembled in a rear area, towed by tank to the minefield's edge, pushed into the minefield, and fired. The triple line charge will clear a 6-meter-wide path along the entire length of the charge. A squad can assemble a 500-meter-long triple charge in 1 to 1.5 hours.

Bangalore torpedoes are also used. Sections, 2 meters in length, carrying 6 kilograms of explosive, are connected by collars. The clearance depth of a path 1 to 2 meters wide is limited only by the manageable weight that can be manually pushed into the minefield.

The number of lanes to be cleared depends on the terrain and the number of columns in the assault echelon. For a leading battalion in the assault on a main axis, six to eight lanes may be required, one for each assaulting platoon. In secondary sectors, as few as two lanes may be sufficient. However, an average of four to six lanes can be expected with at least two developed into permanent lanes, 6 to 8 meters wide, for passage of artillery and logistic vehicles. Engineers mark minefield lanes and provide traffic control through the minefield. The routes leading from a start line to each lane are marked with red triangular metal flags and black-and-white tapes. Illuminating markers may be used at night. Routes through friendly minefield are marked by signs of various shapes placed not less than 20 meters apart on both sides of the route. If possible, they are positioned so as not to be visible from enemy positions.

In attacking from line of march, manual mine breaching is carried out only under certain conditions:

  • As nuisance minefield along or on routes, especially around craters and demolitions, to allow the route clearing unit to work freely.
  • On approaches to water obstacles and water mines.
  • To maintain surprise, especially at night or when the threat wishes to make a gap in their own minefields.
  • When other mine breaching equipment is committed.

When conducting assault breaching operations against a defended enemy minefield, the usual practice is to attack with combined arms teams led by combat engineers and supported by artillery and tactical aviation. Such a formation is necessary if the combat engineers are not to suffer crippling losses to defensive fires. Artillery, in particular, plays a major role in suppressing defensive fires and allowing the execution of engineer tasks. If artillery support is not available or is too short in duration, the first wave of the attack is led by plow-and roller-equipped tanks, while combat engineers closely follow to widen lanes. Here again, the use of plow-and roller-equipped tanks is not an engineer responsibility, but an engineer function carried out by tank soldiers. Another means of lane improvement entails mine clearing tanks dragging a variable length of explosive line charge. The charge is detonated to clear mines not uncovered by the plow or roller. Our minefield should be deep enough to preclude the threat from breaching the entire depth with one line charge. The threat breaching capability with one line charge is curently in the 50-meter range. A threat squad can assemble a 500-meter-long triple charge in 1 to 1.5 hours by coupling the 50-meter sections together. Planners should check the current threat capability for breaching before determining what size minefield is most effective.

As with much of threat engineer activity, threat mine and countermine operations provide both intelligence and tactical values to friendly forces. Minefield breaching activity is indicative of impending threat offensive action, and the identification of such activity will greatly assist in determining times and locations of attack. However, it must be kept in mind that threat doctrine calls for the conduct of bogus mine clearing activity as part of cover and deception plans. Tactically, the denial of threat countermine actions serves to deprive the threat commander of the tactical initiative which his entire operation plan is based.

River crossings

Threat military doctrine dictates that, whenever possible, water obstacles along a broad front are crossed at multiple points without pause in the march or the advance. This tactic is designed to rapidly overwhelm enemy defenses and maintain the tempo of the attack. In the threat view, a delay at a major water obstacle can jeopardize the success of an entire offensive operation in conventional combat, and is certain to destroy large forces massed for the crossing during a nuclear war. Consequently, the threat recognizes two distinct forms of river crossing, hasty and deliberate.

Hasty crossing

The hasty crossing incorporates the features of rapid movement previously mentioned. The attacking force crosses the water obstacle in stride, does not stop to consolidate bridgeheads, and continues the advance without pausing. This is the preferred form of river crossing.

Deliberate crossing

The deliberate crossing is conducted when an attempted hasty crossing has failed, or when hostilities are being initiated against a well-prepared enemy occupying a river line defense. It is characterized by more detailed planning, extensive buildup and preparation, and a greater degree of centralization than the hasty crossing.

The role of combat engineers in both types of crossing is critical. While all arms are fully trained in their individual roles in river crossing operations, engineer functions provide the margin of success. It is not the purpose of this section to examine river crossing operations in their entirety, but to define the role of engineers within the overall effort. For a complete account of the conduct of river crossing operations by all arms, see Defense Intelligence Agency (DIA) Publication DDI-1150-13-77.

Engineer support to assault river crossings by threat forces occurs in the following areas:

  • Engineer reconnaissance of water crossings.
  • Route and site preparation.
  • Crossing preparation and execution.
  • Site protection.
  • Support to units within the bridgehead.

Engineer reconnaissance of water crossings

In the threat view, the key to a successful river crossing is thorough reconnaissance to determine both the tactical situation and the technical characteristics of the river and its banks. As a general principle, reconnaissance will be carried out across a wide front to avoid focusing enemy attention on one area. Additionally, this activity identifies the numerous crossing sites needed to support the crossing of widely dispersed units. Engineer reconnaissance personnel will attempt to ascertain the following information at each site:

  • River width, depth, and current.
  • Entry and exit gradients.
  • River bottom composition.
  • Bank composition and height.
  • Approach and exit routes.
  • Critical terrain features dominating both banks.
  • Possible fording, ferrying, bridging, and snorkeling sites.
  • Information on enemy defenses.

In obtaining this information, engineers may, as in other offensive operations, accompany combined arms reconnaissance teams; or, engineer patrols (IRDs) may operate independently. An IRD will usually operate from the BRDM engineer reconnaissance vehicle and will be equipped with a variety of reconnaissance equipment. In some instances, engineers are clandestinely dropped by parachute directly on the water obstacle.

A typical reconnaissance mission for a squad-size IRD might require the reconnaissance of two sites in a 500- to 600-meter sector, a task usually accomplished in 4 hours. Scuba-equipped engineers check for water mines and test riverbed conditions. Other members of the IRD select and mark concealed approach routes; obtain hydrographic data by using depth finders and water current meters; determine river bank conditions and the presence of existing or military obstacles; identify enemy defenses and conduct bogus reconnaissance activity in other areas to avoid disclosing the main crossing sector.

Significance to Friendly Forces

Engineer reconnaissance performed in support of water crossings has both intelligence and tactical value to the friendly force. Conducting engineer reconnaissance will assist in identifying planned crossing sites for combined arms teams and the times of attack. Such information is of extreme importance in planning the friendly tactical response. Counterreconnaissance, which prevents the accomplishment of engineer reconnaissance missions, deprives the threat commander of information vital to the successful execution of attack.

Route and site preparation

Route preparation of approaches to crossing points will follow the same procedures as in the approach march. Movement support detachments (OODs) will accompany the vanguard elements of advance forces to provide trafficable conditions for the types and numbers of vehicles in the column. A division will usually cross a river on a wide front at a minimum of four points (sometimes up to eight) simultaneously, seeking to find suitable areas for each type of crossing means. This requires the engineer staff to carefully plan and allocate engineer assets.

The preparation of proper entry and exit bank gradients is crucial and depends upon the results of the reconnaissance effort. Earthmoving equipment and explosives are used in preparing bridge approaches and entry and exit points at ford, ferry, and swim sites. Rapid execution of these tasks is essential, since the actual crossing units follow closely behind and depend on suitably prepared crossing points before commencing operations.

Significance to Friendly Forces

Site preparation is a critical phase of a threat river crossing operation. Interference with site preparation activity translates directly to interference with the sequence and timing of the engineer effort, which the entire crossing is dependent upon. If the site preparation effort can be denied, the following crossing units will either be unable to perform their function or forced to halt. The tempo of the attack will be disrupted, and the consequent bunching of units will create lucrative targets. For these reasons, site preparation represents the most vulnerable aspect of a threat river crossing.

Crossing preparation and execution

Following the initial site preparation, and immediately prior to actual crossing, final preparatory activities are executed. Previously located water mines are destroyed by scuba-equipped engineers using explosives. Where necessary, metal matting is emplaced at soft bottom fords. Engineers in amphibious APCs accompany initial assault waves and assist in reducing defenses on the far bank.

During the actual crossing, the ferry operation and bridge emplacement are solely engineer functions. Additionally, engineers are responsible for traffic control and direction at all crossing sites. In the latter role, engineers insure that the crossing is conducted at a high rate of speed, a requirement considered to be extremely important. Threat doctrine establishes the desired crossing time for the division combat elements as 3 hours during daylight and 6 to 8 hours at night.

Significance to Friendly Forces

The primary role of engineers during this phase is providing the physical means by which the bulk of the division crosses. This phase of engineer operations also marks the arrival of major combined arms teams, and is usually supported by artillery fires. In most cases, it will be conducted under the protection of the air defense umbrella.

Site protection

Commencing with initial site preparation and continuing through the conduct of the crossing, engineer elements are responsible for protecting the site, equipment, and combined arms teams from floating mines and enemy raids. Scuba divers and power boats will constantly patrol both upstream and downstream approaches to the crossing site, and outposts will be established along likely land approaches.

Significance to Friendly Forces

When planning raids against threat gap-crossing sites, the presence and locations of these security forces already established by prior reconnaissance should be considered.

Support to units within the bridgehead

As the threat force establishes itself on the opposite bank, elements of the engineer reserve accompany combined arms teams in performing engineer tasks necessary to keep the advance moving. In this role, engineers function in the same manner as when supporting the attack from the line of march or when in contact with the enemy. The crossing site will gradually become the responsibility of lines of communication troops, and the combat engineers will rejoin the division and be prepared to support the next crossing operation.

Significance to Friendly Forces

As with other threat engineer activity, the shift of engineer emphasis accompanies a shift in tactical emphasis. Friendly action which destroys or damages bridging and ferrying equipment during this phase will reduce the threat ability to conduct subsequent river crossings until equipment is replaced.


In order for the threat to attain its primary military principle, Mobility and High Rates of Combat Operations, it is imperative that they preserve their ability to move and maneuver on the battlefield. Threat forces are designed, organized, trained, and equipped to accomplish this principle above all others.

Friendly US countermobility tasks must therefore be designed and executed to slow the movement rate specified by the threat. The use of countermobility by friendly forces must be integrated into the concept of operations not only to impede threat mobility, but to increase the kill probability of friendly firepower. Obstacles must be sited to reinforce the terrain and maximize the effective firepower from friendly battle positions.

Countermobility operations will be used along the FLOT as well as deep into the threat rear area. The use of scatterable minefield gives friendly forces a capability to deny threat mobility anywhere on the battlefield. The use of scatterable minefield should be carefully planned and executed so that friendly mobility during future operations is not impeded.

Countermobility execution is primarily the responsibility of combat engineers. The engineer and the tactical commander must decide early in the planning process how to best position obstacles to increase the effectiveness of friendly fire and maneuver. Tactical commanders must establish countermobility priorities early in the planning process. Early planning will enable maximum effort to be devoted to those countermobility tasks deemed most critical.

Countermobility activities are essential in order to defeat the first principle of the threat army; that is, delay, channel, or stop the offensive movement. An analysis of recent wars shows that effective and well-planned integration of countermobility activities and firepower can enable an outnumbered force to win.


In supporting offensive operations, the role of threat combat engineers is to keep the offense moving. The extreme importance of this effort to the overall conduct of the offense cannot be overemphasized. As has been noted, threat offensive combat is predicated upon mobility, high rates of advance, surprise, and secrecy, and the close coordination of all arms. While first appearing to be highly fluid in nature, close inspection reveals threat style offensives to be predicated upon the carefully synchronized and sequenced interplay of rapidly moving units.

The mission of engineers is to create conditions of movement which will allow this noticeably complicated activity to occur unhindered, and enable the threat commander to enjoy total tactical initiative while denying it to the enemy.

Combat engineers are thus one of the key elements of the offense. Any friendly activity which prevents combat engineers from accomplishing their mission will seriously interfere with the actions of combined arms teams and create exploitable tactical situations for the friendly commander.

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One Billion Americans: The Case for Thinking Bigger - by Matthew Yglesias