From the Boresight Line

Engagements in Undulating Terrain

By 1SG Michael Stephens

January 1, 2025 | Armor, Winter 2025 Edition

Read Time: < 8 mins

“The primary mission of armor units is to close with and destroy the enemy. Tank units perform this mission by a penetration or envelopment of the enemy position, following the exploitation and pursuit of the defeated enemy forces. Even in a defensive situation, tanks are used offensively as the principal element of the counterattack force or mobile reserve. In either situation, the mission is accomplished by employing firepower and maneuver.”1

—Headquarters, Department of the Army, 1961

Currently, the U.S. Army focuses training for armor vehicle crews on operations in open terrain. However, given the diverse nature of potential battlefields, it is crucial to adapt these training and operational paradigms to address challenges posed by undulating terrain effectively. Crews must exercise adaptability, conduct terrain analysis, conduct training and preparation, and be experts when using their equipment and technology. Effective coordination among vehicle crews involves clear communication, understanding of roles and responsibilities, and constant vigilance. Each crew member should contribute to the collective understanding of the situation by monitoring their surroundings, communicating relevant information, and staying informed about the overall mission objectives and potential threats. The ability of maneuver platform crews to effectively operate and succeed in diverse types of terrain is paramount.

Dividing the battlefield into sectors or quadrants assists with quicker target detection and engagement, and undulating terrain often naturally lends itself to this approach. By dividing the battlefield into sectors or quadrants, crews can systematically scan each area for potential threats. This organized approach helps streamline the process of target detection, ensuring that the crew does not overlook any areas and that they can quickly identify enemy positions or movements within their assigned sector. Once a target is detected, crews can focus their attention and firepower on engaging threats within their designated sector. This allows for more efficient target engagement, as crews can prioritize and engage threats based on their proximity and level of threat. Undulating terrain often features natural landmarks or terrain features that naturally divide the battlefield into quadrants or sectors. Hills, ridgelines, valleys, and other prominent features can serve as boundaries between sectors, making it easier for crews to establish their sectors of responsibility and maintain awareness of their surroundings. By dividing the battlefield into sectors, crews operating in undulating terrain can enhance their ability to detect, engage, and neutralize threats effectively while maintaining situational awareness and control over their assigned area of operations. This organized approach maximizes the crew’s combat effectiveness and contributes to the mission’s success.

Armor vehicle platform crews must be adaptable to diverse types of terrain. Whether it is the open expanse of a desert or a rugged, undulating landscape, crews need to adjust their tactics, techniques, and procedures to navigate and engage effectively. Understanding the specific challenges and opportunities presented by different terrain is essential. In open terrain, like deserts, visibility may be high, but cover and concealment are limited. In undulating terrain, natural features may provide cover but restrict movement and line of sight. Crews must analyze the terrain to exploit its features while mitigating its challenges.

Crews must undergo rigorous training in various terrain to build proficiency. This includes understanding how different terrains affect vehicle mobility, line of sight, and firing positions. Training simulations and exercises in diverse environments help crews develop the skills needed to succeed in any scenario. The dynamics of warfare change significantly in restricted terrain, such as urban environments, dense forests, or undulating terrain. The crews’ maneuverability is limited, visibility is often obscured, and reaction times are compressed. Under such conditions, the traditional role of the tank commander expands to encompass more collaborative decision-making and delegation of tasks among the crew. Each crew member needs to be proficient in their primary role and understand the broader context of the platform’s capabilities and limitations. Communication within the crew becomes even more critical as they must coordinate actions swiftly and efficiently. Anticipation of enemy movements becomes paramount in such scenarios. The crew must constantly assess the environment, gather intelligence, and predict potential threats. Success in restricted terrain hinges on the cohesion and expertise of the entire tank crew, working together as a synchronized team to overcome the challenges posed by the environment and the enemy.2

Figure 1. U.S. Soldiers assigned to 3rd Battalion, 8th Cavalry Regiment, review boresight procedures for an M1A2 Abrams tank at Bemowo Piskie Training Area, Poland, Oct. 15, 2025. (U.S. Army National Guard photo by PFC Andre Gremillion Jr.)

Knowing the limitations of the platform’s fire control system and compensating for them is crucial for vehicle commanders. When engaging targets above or below the vehicle’s plane, the angle of sight changes, affecting the ballistic solution calculated by the fire control system. Since the system may not adjust for these angles, vehicle commanders must rely on standard sight adjustments to ensure accurate firing, especially when in a defensive posture. However, operators must ensure that the inputs are as correct as possible to maximize the effectiveness of the ballistic solution. By making simple manual adjustments, commanders can increase the likelihood of hitting the target with subsequent rounds.

Platform capabilities and limitations also significantly affect a crew’s ability to fight and win in undulating terrain. Understanding gun/sight offsets is crucial for the successful engagement of targets when the target is located above or below the firing platform’s position. By properly adjusting the gun or sight angle, crews can compensate for factors such as target distance, elevation changes, and ballistic characteristics of the projectile, increasing the likelihood of hitting the target. The crew’s ability to apply correct standard sight adjustments, adjusting one half or one target form above the target depending on elevation difference, will ensure the highest probability of first-round hit when engaging a target above or below their firing position. These adjustments allow the crew to adapt to dynamic and complex combat situations and engage targets accurately across different ranges and terrains.

Engagements in restricted terrain such as urban environments or dense forests often occur at closer ranges compared to open terrain battles. Because such environments limit visibility and maneuverability, crews are required to engage targets at shorter distances. The restricted space and limited fields of fire make it difficult to engage targets at long ranges. Instead, combatants may face adversaries at ranges well below what might be considered normal battle sight ranges. In these situations, tactics and weapon employment must adapt accordingly. Short-range engagement techniques and rapid target acquisition become essential. Furthermore, situational awareness and understanding of the terrain become necessary for survival. Crews must anticipate potential ambush points, chokepoints, and avenues of approach, adjusting their movements and positioning to maximize cover and minimize exposure. Training in realistic and simulated environments can help prepare soldiers for engagements in restricted terrain, ensuring they are proficient in the unique challenges presented by such environments and capable of effectively engaging targets at close ranges while maintaining control and situational awareness.

Target scanning and acquisition techniques must be adapted and refined when operating in undulating terrain compared to open terrain. The gunner must be able to engage targets in three power using the day sight or thermal imaging system (TIS) channels.3 The day sight, equipped with a gunner’s primary sight (GPS), provides the gunner with clear visibility and target identification capabilities in daylight conditions. It offers high-resolution imagery and facilitates precise aiming and engagement of targets, particularly in well-lit environments. The thermal channel, integrated into the sight system, enables the gunner to detect and engage targets based on their heat signatures. Thermal imaging can penetrate darkness, some smoke, and camouflage. This capability is valuable in low-light conditions, at night, or in environments with limited visibility.

Operating in three power, the gunner possesses a versatile magnification level that facilitates effective target identification and engagement, particularly for troop targets, while maintaining situational awareness of surrounding areas. This enhances overall situational awareness and allows for rapid response to emerging threats or changes in the battlefield environment. The three-power magnification level strikes a balance between magnification and field of view, providing the gunner with a wide enough view to maintain awareness of the broader battlefield while still enabling precise target engagement. This flexibility allows for quick transitions between engaging troop targets and addressing other threats as needed. After a gunner has acquired a threat signature in the wide field of view, three power, they will switch to a narrow field of view, 10x or greater magnification, to conduct a detailed search of that area. Once the target has been located, the gunner can engage and destroy the threat in either field of view. After the engagement has been completed, the gunner will revert to a wide field of view to continue scanning for additional threats on the battlefield.

Through rigorous training focused on fighting in undulating terrain against an enemy seeking to exploit the terrain advantages, armor vehicle crews will become well-versed in the platforms’ capabilities and limitations and become experts in terrain and situational analysis. Each crew member will become proficient in providing information and communication on the battlefield pertinent to the crew’s survival. In restricted terrain, the mobility and firepower provided by armored platforms can still be crucial. While the maneuverability of armored forces might be limited compared to more open terrain, their protection and firepower capabilities often outweigh these limitations with a well-trained crew.

Notes