TACTICS

Tactics are the employment, ordered arrangement, and directed actions of forces in relation to each other. Leaders select tactics that accomplish their assigned mission. Successful tactics require generating and applying combat power. This publication introduces the basic concepts and control measures associated with the science of tactics and provides a common baseline for Soldiers and leaders to execute offensive, defensive, and enabling operations. Soldiers and leaders who know these basic tactics are better prepared to adapt them quickly based on the mission variables of mission, enemy, terrain and weather, troops and support available—time available, civil considerations, and informational considerations [METT-TC(I)]. Tactics require judgement in application. The tactics discussed in this publication focus on the Army’s strategic role of prevailing during large-scale combat operations. Their application must be tempered by the obligation to protect the civilian population. The ability to seize and secure terrain, with its population and productive capacity, distinguishes land forces conducting offensive, defensive, or enabling operations. FM 3-90 provides a common framework for leaders from squad through corps echelon to conduct tactical operations in which leaders seek to find the enemy, fix the enemy, finish the enemy, and follow-through to achieve their objectives. This manual is not prescriptive, but it is authoritative. FM 3-90 (Tactics) merges the 2013 versions of FM 3-90-1 (Offense and Defense Volume 1) and FM 3-90-2 (Reconnaissance, Security, and Tactical Enabling Tasks Volume 2) into a single comprehensive volume on offensive, defensive, and enabling operations. A highlight of changes includes:  Created and became the proponent for the "tactical framework" - which is find, fix, finish, and follow through. This framework is how all offensive and defensive operations are described.  Changed actions on contact from a 5-step process to a new 4-step process – “react”, “develop the situation”, “choose an action”, and “execute and report”.  Removed defeat as a tactical mission task.  Removed ambush as a tactical mission task, which was a mistake in the 2019 version of ADP 3-90.  Changed the form of maneuver of “frontal assault” back to “frontal attack.”  Added mobility, countermobility, link-up, and tactical deception as types of enabling operations.  Made feint and demonstration as variations of tactical deception, instead of variations of an attack.  Described what are forms of contact and added influence as a form of contact.  Removed forms of defense and made them variations of an area defense.  Changed the variations of troop movement from administrative movement, approach march, and tactical road march to tactical and nontactical movements.  Removed encirclement as an enabling operation. It is still a desired outcome, and there is special planning required to create, maintain, reduce, and when encircled, break out of an encirclement, so that information was moved to an appendix.  Removed the tactical mission tasks categories of "actions by friendly forces" and "effects on enemy forces."  Modified, removed, or added over 140 definitions to make it easier to read and understand.  Added graphics for all offensive and defensive operations.  Made numerous other changes to enhance readability and understanding. FM 3-90 is divided into four parts, consisting of twenty chapters and three appendices. Part One (chapters 1-2) focuses on the overall concept of tactics and maneuver. Part Two (chapters 3-7) focuses on offensive operations. Part Three (chapters 8-11) focuses on defensive operations. Part Four (chapters 12-20) focuses on enabling operations. Appendix A describes tactical control measures. Appendix B describes tactical mission tasks. Appendix C describes encirclements.

major update in this chapter is the expansion of the cordon and search section. Chapter 5 (Attack) introduces and describes general considerations, organization of forces, common control measures, and conduct of the four variations of an attack. The major update in this chapter is moving demonstration and feint from the variations of an attack to chapter 19 (Tactical Deception).

variations of a retrograde. The major update in this chapter is changing the retrograde tasks to variations of the retrograde. fundamentals, methods, and forms of reconnaissance. The major updates in this chapter are updating the commander’s reconnaissance guidance, tasks within the forms of reconnaissance, and reconnaissance fundamentals.

Chapter 17 (Countermobility) introduces and describes the general considerations for countermobility, terrain reinforcement, obstacle intent, obstacle employment principles, and obstacle emplacement. This is a new chapter and makes countermobility an enabling operation. Chapter 18 (Mobility) introduces and describes the general considerations of and the types of mobility tasks. This is a new chapter and makes mobility an enabling operation.

and demonstration from an offensive operation to a variation of tactical deception. Chapter 20 (Linkup) introduces and describes the general considerations and conduct of link up operations. This is a new chapter and makes linkup an enabling operation.

Part One introduces tactics and forms of maneuver. Chapter 1 describes the role of tactics, operational and mission variables, and the general considerations for tactics. Chapter 2 covers the movement formations, techniques, and the forms of maneuver.

Commanders use offensive operations to defeat and destroy enemy forces as well as to seize terrain, resources, and population centers. Part Two consists of five chapters that describe the fundamentals of the offense and the four types of offensive operations—movement to contact, attack, exploitation, and pursuit.

Commanders use defensive operations to destroy enemy forces; to retain terrain, resources, and population centers; and to regain the initiative. Part Three consists of four chapters that describe the fundamentals of the defense and the three types of defensive operations—area defense, mobile defense, and retrograde.

Enabling operations are operations that connect offensive, defensive, and stability operations together. On their own, they are not decisive, but they help set conditions for the execution of all operations. They are complex enough that they require a either a deliberate planning effort or a well developed and understood SOPSOPStandard Operating Procedures to execute. Part Four consists of nine chapters that describe reconnaissance, security operations, troop movement, relief in place, passage of lines, countermobility, mobility, tactical deception, and link-up operations.

This appendix expands the control measure discussion from Chapter 1 and explains maneuver control measures, fire support coordination measures, and airspace coordination measures common to offensive, defensive, and enabling operations. These control measures apply to both automated and hand drawn graphics or symbols, displays, and overlays. Most tactical control measures are used in both planning products and operation overlays. GENERAL CONSIDERATIONS FOR CONTROL MEASURES A-1. Units use control measures to assign responsibilities, coordinate the warfighting functions, control operations, and prevent fratricide. Well-conceived control measures facilitate current and future operations. Throughout an operation, commanders adjust control measures as necessary to maintain synchronization and ensure mission accomplishment. A-2. Control measures apply to all forces. Control measures are used throughout the operations process and are graphically depicted within digital systems and on analog map overlays. Commanders ensure that all higher echelon control measures are incorporated into their units’ orders and common operational picture. Subordinate units develop additional control measures to command and control their forces and ensure those control measures are shared with adjacent, higher, and subordinate units and staffs. They reference the control measures established by higher headquarters when making reports to that headquarters. A-3. Units generally establish and follow standard operating procedures for naming common control measures. During operations, units follow the timelines or procedures prescribed by their higher headquarters regarding control measure updates. For example, a division artillery headquarters will normally establish rhythmic times for subordinate units to provide updates to their current and planned fire support coordination measures. A-4. The sections below consist of common maneuver control measures, fire support coordination measures, airspace coordination measures, and obstacle control measures. These control measures are not a comprehensive listing of all possible control measures a unit may employ during operations. (See FM 1-02.2 for a listing of all control measures.) MOVEMENT AND MANEUVER CONTROL MEASURES A-5. Maneuver control measures are used by maneuver forces and headquarters at all echelons to control the movement and maneuver of forces. Paragraphs A-7 through A-41 list and describe control measures commonly used during offensive, defensive, and enabling operations. Paragraphs A-44 through A-61 list and describe control measures commonly used in offensive operations while paragraphs A-62 through A-79 include those control measures that are only applicable to defensive operations. Paragraphs A-80 through A-88 include direct fire control measures. C OMMON C ONTROL M EASURES A-6. Many graphical control measures are applicable to offensive, defensive, and enabling operations. The following are control measures discussed throughout FM 3-90. However, this list is not inclusive of all control measures. For a comprehensive listing of all approved control measures see FM 1-02.2. Area of Operations A-7. An area of operations is an operational area defined by a commander for land and maritime forces that should be large enough to accomplish their missions and protect their forces (JP 3-0). An area of operations (AO) is always completed enclosed by boundaries. An AO could consist of a singular boundary. An AO can also be enclosed with forward, rear, and lateral boundaries as shown in figure A-1. Figure A-2 depicts a division AO with subordinate BCTBCTBasic combat training assigned areas. See paragraph 1-56 for more information on an AO. Assembly Areas A-8. An assembly area is an area a unit occupies to prepare for an operation. Units of all types and echelons can be assigned assembly areas. In figure A-3 on page A-4, are examples of multiple units occupying one assembly area is a graphical shortcut taken when the map scale makes depiction of multiple assembly areas unreadable. In reality, the higher echelon commander would subdivide ASSEMBLY AREA THOMAS into two smaller assembly areas, one for each unit. A unit assembly area is normally within the assigned area of a higher headquarters and are typically noncontiguous. This means that a unit has the same responsibilities within its assigned assembly area as it has for any other assigned area. A-9. A tactical assembly area is an area that is generally out of the reach of light artillery and the location where units make final preparations (precombat checks and inspections) and rest, prior to moving to the line of departure (JP 3-35). Tactical assembly areas are where enemy contact is likely and the commitment of a unit into combat is possible or anticipated. Examples of tactical assembly areas include locations occupied by units designated as tactical reserves, by units after completing a rearward passage of lines, temporarily by units during tactical movement, and by units during reconstitution. Units in tactical assembly areas are typically preparing to move forward to execute a forward passage of lines followed by offensive operations or have been assigned a reserve mission by their higher commander. A-10. Planning for, occupying, and departing an assembly area is difficult and time consuming and requires careful consideration. Ideally, an assembly area provides—  Concealment from air and ground observation.  Adequate entrances, exits, and internal routes.  Space for dispersion  Enough distance from other areas and units to preclude mutual interference.  Cover from direct fire.  Good drainage and soil conditions that can sustain unit vehicles and individual Soldier movements.  Terrain masking of electromagnetic signatures.  Terrain allowing observation of ground and air avenues into the assembly area.  A location beyond enemy medium artillery range. A-11. The proper location and size of assembly areas contributes significantly to both security and flexibility. The location should facilitate future operations, so movement to subsequent positions can take place smoothly and quickly by concealed routes. An assembly area must be large enough to accommodate the type and size of the force occupying it. Generally, dismounted infantry assembly areas are smaller than those assigned to armored or Stryker units. Because of their smaller signature, infantry units can use assembly areas closer to enemy forces than armored and Stryker units without excessive risk of enemy detection. The tactical mobility of armored and Stryker units allows them to occupy assembly areas at a greater distance from the LD than infantry units. A-12. There are three methods to organize an assembly area: as a single area, as part of a large assembly area, or dispersed. The biggest difference between the three methods is the amount of security required since every assembly area inherently conducts a perimeter defense. See Figures A-4, A-5, and A-6 for examples of each method. A-13. The single area method configures a unit in a perimeter defense with maneuver units deployed along the entire perimeter. Command and control, sustainment, and any other supporting units are located within the interior of the assembly area. Figure A-4 is an example of a single area assembly area for a battalion task force. A-14. A unit can also occupy a portion of a larger assembly area. This typically occurs when a subordinate formation occupies a portion of their higher headquarters assembly area. With this method, a unit has boundaries with adjacent units and may only have a portion of their assembly area focused on a perimeter. See figure A-5 for an example of an armor battalion occupying a portion of a larger assembly area. A-15. A unit may also use a dispersed method to assign assembly areas. In this method subordinate units are assigned individual assembly areas. These subordinate units maintain their own 360-degree security. Similar to the single assembly area method, maneuver units occupy perimeter assembly areas with command and control, sustainment, and other units located within the interior. See figure A-6 on page A-6 for an example of the dispersed method by a division. Boundaries A-16. A boundary is a line that delineates surface areas for the purpose of facilitating coordination and deconfliction of operations between adjacent units, formations, or areas (JP 3-0). Boundaries are normally drawn along identifiable terrain features and are used to delineate responsibility between adjacent units and between higher and lower echelon headquarters. Boundaries should not split responsibilities for key or decisive terrain, roads, rivers, or railways. Within their assigned areas, units may maneuver within the overall plan without close coordination with neighboring units unless otherwise restricted. Direct fire may be placed across boundaries on clearly identified enemy targets without prior coordination, provided friendly forces are not endangered. Indirect fire also may be used after prior coordination with the adjacent unit. Commanders adjust boundaries as necessary in response to the evolving tactical situation. A-17. Boundaries by themselves or with other control can be used to define a unit’s assigned area: area of operations, zone, or sector. A forward boundary is a boundary that delineates the forward edge of a unit’s area of operation. A lateral boundary is a boundary defining the left or right limit of a unit’s assigned area. A rear boundary is a boundary that delineates the rearward limits of a unit’s assigned area. The forward boundary is the farthest limit in the direction of the enemy, of an organization’s responsibility. The rear boundary also defines the start of the next echelon’s rear area. Figure A-1 on page A-2 depicts an AO with forward, rear, and lateral boundaries. Checkpoint A-18. A checkpoint is a predetermined point on the ground used to control movement, tactical maneuver, and orientation. Checkpoints are used by all units in all types of operations. Units may use checkpoints to supplement or as substitutes for phase lines. Units can also use a checkpoint as a fire control measure in lieu of the preferred control measure, a TRP. Figure A-7 depicts CHECKPOINT 13. Contact Point A-19. In land warfare, a contact point is a point on the terrain, easily identifiable, where two or more units are required to make contact (JP 3-50). A commander establishes a contact point where a PL crosses a lateral boundary or another identifiable terrain feature as a technique to ensure coordination between two units. The commander provides a date-time group to indicate when to make that physical contact. Figure A-8 depicts CONTACT POINT 8. A-20. If both units are moving or are stationary, the mutual higher echelon commander normally designates the location of contact points and times of contact. When one unit is stationary, its commander normally designates the location of the contact point and the meeting time and transmits this information to the commander of the moving unit. Coordination Point A-21. A coordination point is a point that indicates a specific location for the coordination of tactical actions between adjacent units. It is used when a PL crosses a lateral boundary between two units or whenever a boundary crosses the forward edge of the battle area (FEBA). The difference between a contact point and a coordination point is that the establishing headquarters does not dictate the exact time when contact is required. Figure A-9 depicts a coordination point. Forward Line of Own Troops A-22. The forward line of own troops is a line that indicates the most forward positions of friendly forces in any kind of military operation at a specific time. The forward line of own troops (FLOT) normally identifies the forward location of security forces. In the defense, it may be beyond, at, or short of the FEBA. It does not include small, long-range reconnaissance assets and similar stay-behind forces. Friendly forces forward of the FLOT may have a restrictive fire coordination measure, such as a restrictive fire area (RFA), placed around them to preclude friendly fire incidents. An enemy FLOT indicates the forward most position of enemy forces. Figure A-10 depicts the symbol for the FLOT. Gap A-23. A gap is an area free of obstacles that enables forces to maneuver in a tactical formation. It is wide enough to allow a friendly force to pass through while dispersed in a tactical formation. The presence of gaps prevents inadvertent concentrations of Soldiers and equipment around the entry points of lanes. Figure A-11 depicts the graphic control measure for a gap. Infiltration Lane A-24. An infiltration lane is a control measure that coordinates forward and lateral movement of infiltrating units and fixes fire planning responsibilities. Commanders select infiltration lanes that avoid enemy forces, provide cover and concealment, and facilitate navigation. Each unit assigned an infiltration lane picks its own routes within the lane and switches routes as necessary. The left and right limits of the infiltration lane act as lateral boundaries for the unit conducting the infiltration. Staffs must coordinate with the infiltrating unit any attacks by rotary-or fixed-wing aircraft, indirect fires, or munitions effects that impact the lane. Units leaving their assigned lane run the risk of impact by friendly fires. Company-sized units normally have a single infiltration lane, although they can use more than one lane. Larger organizations are always assigned more than one infiltration lane. Figure A-12 depicts the graphic control measure for INFILTRATION LANE MICHAEL. lane MICHAEL Line of Contact A-25. The line of contact is a general trace delineating the location where friendly and enemy forces are engaged. Units develop their line of contact (LC) based on the maximum effective range of the direct fire weapons systems or the visual line of sight from known or templated enemy locations. The commander designates the enemy side of the LC by the abbreviation “ENY.” In the defense, a LC is often synonymous with the FLOT. In the offense, commanders may combine the LC with the LD. When combined with the LD, it is represented by a phase line with LD/LC written next to the name. Figure A-19 on page A-11 depicts PL JOHN being used as a LD/LC. A-26. For other forms of contact, a phase line can be designated as a probable line of contact. For example, based on IPB and information collection friendly forces can depict known or anticipated locations of enemy artillery assets and determine a probable line of contact for enemy indirect fires. Figure A-13 shows an example line of contact. Linkup Point A-27. A linkup point is a designated place where two forces are scheduled to meet. This easily identifiable point on the ground is where two forces meet or consolidate before proceeding on with their mission. Besides being easily identifiable, the linkup point must also be rather inconspicuous, or the enemy will be able to predict the location of the coordination and quickly target it. It should also be relatively isolated from direct fire and observation of possible enemy elements located on the surrounding terrain. Alternate linkup points must meet the same criteria and should be reconnoitered to the same degree as primary linkup points. Linkup points are normally positioned behind or along one flank of the enemy’s positions on defensible terrain and located away from normal enemy troop movement routes. The linkup point should be large enough for all infiltrating elements to assemble, and it should offer cover and concealment for these elements. Figure A-14 depicts LINKUP POINT 8. Named Area of Interest A-28. A named area of interest is the geospatial area or systems node or link against which information that will satisfy a specific information requirement can be collected, usually to capture indications of enemy and adversary courses of action (JP 2-0). In this latter case, the NAI may be a person, group, or portion of cyberspace. Staffs tailor the shape of their NAI symbols to the actual area they want observed rather than using a prescribed shape. It is possible to re-designate a NAI as a target area of interest (TAI) when Soldiers confirm enemy activity in the area and have assets that can target it. This allows commanders to mass the effects of combat power on that area. Figure A-15 depicts NAI AUGUSTA. Objective A-29. An objective is a location used to orient operations, phase operations, facilitate changes of direction, and provide for unity of effort (ADP 3-90). Objectives should be easily identifiable on the ground to facilitate their recognition. They normally assign subordinate commanders only their final objectives, but they can assign intermediate objectives as necessary. Figure A-19 on page A-11 depicts OBJECTIVE PAT. OBJECTIVE PAT is further divided into two subordinate objectives: OBJECTIVE KAI and OBJECTIVE ZEKE. Passage Lane A-30. A passage lane is a lane through an obstacle that provides safe passage for a passing force. It is a clear route through an obstacle. The lane may be cleared, including being reduced and proofed, as part of a breach operation, or it may be included as part of the design of a friendly obstacle. Passage lanes normally end where a route begins. That route should allow the passing unit to move rapidly through the stationary unit’s area. Figure A-16 depicts the graphic control measure for a passage lane. Passage of Lines A-31. A passage of lines occurs under two conditions. A forward passage of lines occurs when a unit passes through another unit’s positions while moving toward the enemy (ADP 3-90). A rearward passage of lines occurs when a unit passes through another unit’s positions while moving away from the enemy (ADP 3-90). Ideally, a passage of lines does not interfere with the conduct of the stationary unit’s operations. Figure A-17 shows the symbols for both a forward and a rearward passage of lines. The arrow goes in the direction the passing unit is moving. rearward passage of lines Passage Point A-32. A passage point is a designated place where the passing units pass through the stationary unit. The location of this point is where the commander wants subordinate units physically to execute a passage of lines. Figure A-18 depicts the graphic control measure for PASSAGE POINT 7. Phase Line A-33. A phase line is an easily identified feature in the operational area utilized for control and coordination of military operations (JP 3-09). A commander establishes PLs to control the maneuver of the units. PLs are not boundaries unless designated as such and do not establish any specific responsibilities between units, unless the operation order so specifies. When possible, commanders place them along easily recognizable terrain features—such as roads, railroad tracks, rivers, and ridgelines—to ensure easy identification. Units normally report crossing PLs, but do not halt unless specifically directed. Some PLs have additional designations for specific purposes, such as an LD or a PLD. Figure A-19 depicts five phase lines being used for an offensive operation. Position Area for Artillery A-34. A position area for artillery is an area assigned to an artillery unit to deliver surface to surface fires. A position area for artillery (PAA) is not an AO for the artillery unit occupying it. Commanders assign PAAs for terrain management and for locations where individual artillery systems can maneuver to increase their survivability. Establishing a PAA lets other subordinate units know they should avoid occupying that same terrain. While the exact size of a PAA depends on mission variables, a Paladin platoon normally requires a PAA encompassing over 4 square kilometers whereas a multiple launch rocket system (known as MLRS) platoon requires 9 square kilometers. Figure A-20 depicts a PAA. A-35. The maneuver echelon operations officer of the unit that owns the terrain establishes the PAA. The occupying artillery unit does not have the same authority and responsibilities toward the PAA that are associated with a unit assigned an assigned area. For example, other units can move through a PAA without clearing that movement with the artillery unit. However, to prevent fratricide or inadvertently concentrating forces units should make attempt to contact the artillery unit to determine if the PAA is occupied. Additionally, units moving through or occupying terrain within a PAA should be cognizant of the increased risk of receiving indirect fire from enemy artillery due to enemy counterbattery or preparatory fires. The artillery unit occupying a PAA establishes liaison with the unit that owns the assigned area where the PAA is located. The echelon fire support officer usually conducts this liaison in accordance with standard command and support relationships. A-36. The decision to establish a PAA affects airspace control for rotary-wing, fixed-wing, unmanned, and tilt-rotor aircraft integration. A PAA is a base upon which to establish future grid target lines for lateral deconfliction and areas for rotary-wing, fixed-wing, unmanned, and tilt-rotor aircraft to avoid, depending on high or low angle artillery fires. Rally Point A-37. A rally point is an easily identifiable point on the ground at which units can reassemble and reorganize if they become dispersed. Forces conducting a patrol or an infiltration commonly use this control measure. Figure A-21 depicts RALLY POINT 14. Release Point A-38. A release point is a designated place on a route where elements are released from centralized control. Once released from centralized control they are released back to the authority of their respective commanders. Each start point (SP) must have a corresponding release point (RP), which must also be easy to recognize on the ground. Marching units do not stop at the RP; instead, as they move through the RP and continue toward their own appropriate destination. Figure A-23 shows RP 3 on ROUTE IRON. Relief in Place A-39. A relief in place is an operation in which, by direction of higher authority, all or part of a unit is replaced in an area by the incoming unit and the responsibilities of the replaced elements for the mission and the assigned zone of operations are transferred to the incoming unit (JP 3-07.3). Figure A-22 depicts a relief in place. (See Chapter 15 for more information on relief in place.) Route A-40. A route is the prescribed course to be traveled from a point of origin to a destination. Routes can have different functions. Commanders can add those functions as adjectives to specify different types of routes. Examples of such routes include a passing route, main supply route, and alternate supply route. Commanders can further designate routes as open, supervised, dispatch, reserved, or prohibited. They can assign names, numbers, or alphanumeric designations to routes within their assigned areas. Figure A-23 depicts ROUTE IRON. Start Point A-41. The start point is a designated place on a route where elements fall under the control of a designated march commander. All routes have a designated SP and RP that are easily recognizable on the map and on the ground, such as a road junction. It is far enough from the assembly area to allow units to organize and move at the prescribed speed and interval when they reach the SP. Figure A-23 depicts SP 7 on ROUTE IRON. Target Area of Interest A-42. A target area of interest is the geographical area where high-value targets can be acquired and engaged by friendly forces (JP 2-0). Commanders use TAIs to apply a specific effect against a specific target with a defined outcome. The difference between a TAI and an NAI is that an NAI is established to obtain information and answer a specific information requirement whereas a TAI is established to create a pre-determined effect. The unit staff develops TAIs during the MDMP, based on the currently available products resulting from the IPB. These TAIs are further refined during course of action analysis and finally approved by the commander during course of action approval. The shape of a TAI reflects the target and effect intended for the TAI. Information collection assets normally cue their use. Commanders designate TAIs for any organic or supporting systems. TAIs differ from engagement areas. Engagement areas plan for the use of all available weapons, while TAIs might be engaged by a single weapon or system. Figure A-24 depicts TAI WHITETAIL. WHITETAIL O FFENSIVE O PERATIONS C ONTROL M EASURES A-43. This section defines in alphabetical order those common offensive control measures commanders use to synchronize the effects of combat power. The commander uses the minimum control measures required to successfully complete the mission while providing subordinates the flexibility needed to respond to changes in the situation. Figure A-25 depicts some of the common offensive control measures that will be further discussed throughout this section. Assault Position A-44. An assault position is a covered and concealed position short of the objective from which final preparations are made to assault the objective (ADP 3-90). Assault positions are typically only assigned to attacking maneuver formations. Units supporting and maneuvering with the maneuver force execute their final preparations in the same assault positions as the maneuver force. These final preparations can involve tactical considerations, such as a short halt to coordinate the final assault, reorganize to adjust to combat losses, or make necessary adjustments in the attacking force’s dispositions. These preparations can also involve technical activities, such as engineers conducting their final checks on obstacle clearing systems and the crews of plow and roller equipped tanks removing their locking pins. Commanders may locate their assault positions near either a final coordination line (FCL) or a probable line of deployment (PLD). Figure A-25 depicts ASSAULT POSITION PEGGY. (Paragraphs A-52 and A-57 define a FCL and PLD respectively.) Assault Time A-45. The assault time is the moment to attack the initial objectives throughout the geographical scope of the operation (ADP 3-90). Higher echelon headquarters impose this control measure to achieve simultaneous results from several different units. Using an assault time synchronizes the moment an enemy force feels the effects of friendly combat power. Assault times are similar to the time-on-target control method used by field artillery units when processing fire missions. A commander uses an assault time instead of a time of attack because of differences in distance, tactical mobility, and known obstacles among subordinate units. (See paragraph A-59 for more information on a time of attack). Attack by Fire Position A-46. An attack by fire position designates the general position from which a unit performs the tactical task of attack by fire (ADP 3-90). The purpose of these positions is to mass the effects of direct fire systems for one or multiple locations toward enemy forces. Attack by fire positions rarely apply to units larger than a company. An attack by fire position does not indicate the specific site. Figure A-26 depicts ATTACK BY FIRE POSITION BRANDON. (See paragraph B-3 for more information on the tactical mission task of attack by fire). Attack Position position JAMES A-47. The attack position is the last position an attacking force occupies or passes through before crossing the line of departure (ADP 3-90). An attack position facilitates an attacking force’s deployment and last-minute coordination before it crosses the LD. Located on the friendly side of the LD, an attack position offers cover and concealment for the attacking force. Commanders use it primarily at battalion level and below. Whenever possible, units move through the attack position without stopping. An attacking unit occupies an attack position for various reasons, including when the unit is waiting for specific results from preparation fires or when it is necessary to conduct additional coordination, such as a forward passage of lines. If the attacking unit occupies the attack position, it stays there for the shortest amount of time possible to avoid offering enemy forces a lucrative target. Figure A-25 on page A-14 depicts ATTACK POSITIONS BLUE and GOLD. Axis of Advance A-48. An axis of advance designates the general area through which the bulk of a unit’s combat power must move (ADP 3-90). A commander uses an axis of advance for three primary reasons:  To direct the bypass of locations that could delay the progress of the advancing force, such as known contaminated areas.  To indicate that the force is not required to clear the entire assigned area as it advances. The force will be required to clear the axis based on specified bypass criteria.  To indicate to a unit involved in offensive encirclement, exploitation, or pursuit operations the need to move rapidly toward an objective. A-49. An axis of advance can be used by any maneuver echelon. Subordinate maneuver units can develop their own axis of advance within the confines of their higher headquarters axis of advance. For example, a battalion can establish multiple company level axis of advance as long as each company’s axis of advance remains within the bounds of the battalion’s axis of advance. The width of the axis varies based on factors such as terrain, size and type of friendly forces, and time. Generally, a wider axis of advance is used in unrestricted terrain. When using an axis of advance, the risk is that friendly forces do not detect enemy forces outside the axis and the enemy is inadvertently bypassed. Figure A-25 on page A-14 depicts AXIS OF ADVANCE JAN. When developing the axis of advance, commanders also establish bypass criteria (see paragraph 12-27 for bypass criteria). Battle Handover Line A-50. The battle handover line is a designated phase line where responsibility transitions from the stationary force to the moving force and vice versa (ADP 3-90). The common higher echelon commander of the two forces establishes the battle handover line (BHL) after consulting both commanders. The stationary commander determines the location of the line. The BHL is forward of the FEBA in the defense or the FLOT in the offense. Commanders draw it where the direct fires of forward combat elements of the stationary unit can effectively support the passing unit until completion of the passage of lines. The area between the BHL and the stationary force belongs to the stationary force commander. The stationary force commander may employ security forces, obstacles, and fires in the area. Figure A-27 depicts a BHL at PL DANIEL used in conjunction with other control measures during a forward passage of lines. Direction of Attack A-51. The direction of attack is a specific direction or assigned route a force uses and does not deviate from when attacking (ADP 3-90). It is a restrictive control measure that requires a subordinate unit to attack as indicated and is not normally allowed to bypass the enemy. It is normally used at battalion and lower levels. Direction of attack is a more restrictive control measure than axis of advance and units are not free to maneuver off the assigned route. Direction of attack is normally used in counterattacks or to ensure that supporting attacks make maximal contribution to the main attack. It is also used during night attacks, infiltrations, and when attacking through obscuration. When using a direction of attack, commanders designate a PD at the beginning. Figure A-25 on page A-14 depicts DIRECTION OF ATTACK JOAN. Final Coordination Line A-52. The final coordination line is a phase line close to the enemy position used to coordinate the lifting or shifting of supporting fires with the final deployment of maneuver elements (ADP 3-90). Brigade and below maneuver formations typically use an FCL. The FCL should be placed on easily recognizable terrain. Final adjustments to supporting fires necessary to reflect the actual versus the planned tactical situation take place before crossing the FCL. The FCL is not a FSCM. Figure A-25 on page A-14 depicts PL ROBERT as an FCL. Limit of Advance A-53. The limit of advance is a phase line used to control forward progress of the attack (ADP 3-90). A LOA is a restrictive control measure because the attacking unit does not advance any of its elements or assets beyond the LOA, but the attacking unit can push its security forces to that limit. Units can employ direct and indirect fires beyond the LOA. A LOA is typically established by a higher echelon headquarters. Commanders usually select linear terrain features, perpendicular to the direction of attack, on the far side of the objective as LOAs because such terrain features are easily identifiable. They employ LOAs to prevent overextending the attacking force and to reduce the possibility of fratricide and friendly fire incidents by fires supporting the attack. They position LOAs far enough beyond their objectives to allow their units to defend the objective. A LOA prevents units from exploiting success and launching a pursuit; therefore, commanders should only use LOAs if they do not want to perform an exploitation or pursuit. A forward boundary is always a LOA, but a LOA is not necessarily a forward boundary. In fact, a LOA and the unit’s forward boundary should rarely coincide because of the resulting limitations that a forward boundary places on supporting fires beyond the forward boundary. Figure A-25 on page A-14 shows PL BASIL used as a LOA. Line of Departure A-54. In land warfare, the line of departure is a line designated to coordinate the departure of attack elements (JP 3-31). The purpose of the LD is to coordinate the advance of the attacking force so that its elements strike the enemy in the order and at the time desired. The LD also marks where the unit often transitions from movement to maneuver. Commanders can also use it to facilitate the coordination of fires. Generally, it should be perpendicular to the direction the attacking force will take on its way to the objective. Friendly forces should control the LD. Commanders analyze the terrain before designating an LD. Different units have different movement rates on leaving their assembly areas based on their inherent mobility characteristics and the terrain traversed. Commanders consider these different characteristics when establishing an LD to prevent these differences from affecting the synchronization of the operation. When possible, commanders select the LD so that the terrain the attack unit traverses before crossing the LD provides sufficient cover for the attacking unit’s final deployment into a maneuver formation before crossing the LD. In many cases, the LD is also the LC because the unit in contact is conducting the attack from its current positions. Figure A-25 on page A-14 depicts PL JOHN as a combined LD and LC. Objective Rally Point A-55. The objective rally point is an easily identifiable point where all elements of the infiltrating unit assemble and prepare to attack the objective (ADP 3-90). It is typically near the infiltrating unit’s objective; however, there is no standard distance from the objective to the objective rally point. It should be far enough away from the objective so that the enemy will not detect the infiltrating unit’s attack preparations. Point of Departure A-56. The point of departure is the point where the unit crosses the line of departure and begins moving along a direction of attack (ADP 3-90). Units conducting reconnaissance and security patrols and other operations in a low-visibility environment commonly use a point of departure (PD) as a control measure. Like the LD, it marks the point where the unit transitions from movement to maneuver under conditions of limited visibility. Figure A-28 depicts PD 7. Probable Line of Deployment A-57. A probable line of deployment is a phase line that designates the location where the commander intends to deploy the unit into assault formation before beginning the assault (ADP 3-90). Commanders at battalion-sized and smaller units primarily employ PLDs when their units do not cross their LD in an assault formation. It is usually a linear terrain feature perpendicular to the direction of attack and recognizable under conditions of limited visibility. The PLD should be located outside the range where enemy forces can place the attacking force under effective direct fire. In figure A-25 on page A-14, PL ROBERT is designated as the PLD. Support by Fire Position A-58. A support by fire position designates the general position from which a unit performs the tactical mission task of support by fire (ADP 3-90). Paragraph B-58 defines the tactical mission task of support by fire. The purpose of these positions is to increase the supported force’s freedom of maneuver by placing direct fires on an objective that a friendly force is going to assault. Support by fire positions are located within the maximum friendly direct fire range of the enemy positions. Commanders select them so that a moving assault force does not mask its supporting fires. For this reason, support by fire positions are normally located on the flank of an assault force, elevated above the objective if possible. Support by fire positions are rarely applicable to units larger than company size. When used as a planning symbol, the support by fire position depicted in figure A-29 indicates the general location and direction from which the unit provides fires. When used as a control measure, the position of the symbol dictates the actual location of the position, and the arrows define the left and right limits of the unit’s sector of fire. position Time of Attack A-59. The time of attack is the moment the leading elements of the main body cross the line of departure, or in a limited-visibility attack, the point of departure (ADP 3-90). Commanders use it when conducting simultaneous operations where supporting efforts must accomplish their mission to create conditions for the success of the main effort. When determining a time of attack, they consider the time subordinates require to—  Conduct necessary reconnaissance, prepare plans, and issue orders.  Synchronize plans among all subordinate units.  Complete attack preparations, such as pre-combat inspections.  Move to the LD or PD. A-60. Orders normally designate the time of attack as H hour. This occurs when the main body crosses the LD. However, H-hour can also designate the time to implement a phase of an operation, such as an airborne or air assault phase. The headquarters planning the operation specifies the term’s exact meaning. This is usually a part of the unit’s standard operating procedures. Zone A-61. A zone is an operational area assigned to a unit in the offense that only has rear and lateral boundaries (FM 3-0). By not emplacing a boundary to a unit’s front it allows them to move quicker and synchronize fires better against the enemy they are facing. A zone is different from an area of operations in that instead of a forward boundary to restrict movement and fires a higher headquarters uses maneuver control measures and fire support coordination measures. Example control measures to use include things such as a limit of advance and a coordinated fire line. Zones are most appropriate for any unit likely to make direct fire contact with the enemy during high-tempo offensive operations or when there is a fluid FLOT. Units assigned a zone treat areas behind the FLOT as an AO. Zone can be further subdivided as needed into area of operations, zones, or sectors as appropriate. Any unit not expecting to be in direct fire contact with the enemy should use an area of operations or other means of terrain management. If a unit is attacking in a zone and culminates and transitions to a hasty defense, they will continue to use the zone because they eventually expect to go back on the offense and the defense is a temporary thing. Figure A-30 depicts a battalion zone for 1-66 Armor. D EFENSIVE O PERATIONS C ONTROL M EASURES A-62. The commander controls the defense by using control measures to provide the flexibility needed to respond to changes in the situation and allow the defending commander to rapidly concentrate combat power at the decisive point. Defensive control measures within a commander’s assigned area include designating the security area, BHL, MBA with its associated FEBA, and the echelon support area. The commander can use battle positions and additional direct fire control and FSCMs in addition to those control measures discussed earlier in appendix A to further synchronize the employment of combat power. The commander designates disengagement lines to trigger the displacement of subordinate forces. These common defensive control measures are discussed in alphabetical order in paragraphs A-63 through A-79. Battle Positions A-63. A battle position is a defensive location oriented on a likely enemy avenue of approach (ADP 3-90). A battle position is generally only used during defensive operations. The battle position (BP) is a symbol that depicts the location and general orientation of most of the defending forces. A commander’s use of a battle position does not direct the position of the subordinate’s entire force within its bounds since it is not an assigned area. There are five kinds of BPs—primary, alternate, supplementary, subsequent, and strong point. When assigning BPs, the higher echelon always designates the primary BP. The subordinate unit designates and prepares alternate, supplementary, and subsequent positions as time and other resources permit and if the terrain or situation requires them. Figure A-31 on page A-20 depicts the five kinds of BPs. A-64. The primary position is the position that covers the enemy’s most likely avenue of approach into the assigned area. It is the best position from which to accomplish the mission, such as cover an engagement area. A-65. An alternate position is a defensive position that the commander assigns to a unit or weapon system for occupation when the primary position becomes untenable or unsuitable for carrying out the assigned task. It covers the same area as the primary position. Commanders locate alternate positions so the occupants can continue to fulfill their original tasks, such as covering the same avenue of approach or engagement area as their primary positions. These positions increase the defenders’ survivability by allowing defenders to engage enemy forces from multiple positions. For example, a unit moves to its alternate positions when enemy forces bring suppressive fires on the primary position. A-66. A supplementary position is a defensive position located within a unit’s assigned area that provides the best sectors of fire and defensive terrain along an avenue of approach that is not the primary avenue where the enemy is expected to attack. For example, an avenue of approach into a unit’s assigned area from one of its flanks normally requires establishing supplementary positions to allow a unit or weapon system to engage enemy forces traveling along that avenue. A-67. A subsequent position is a position that a unit expects to move to during the course of battle. A planned and, to some extent, prepared location for a defense or delay that is behind the primary positions initially occupied for a defense. A defending unit may have a series of subsequent positions. Subsequent positions can be further organized into primary, alternate, and supplementary positions. A-68. A strong point is a heavily fortified battle position tied to a natural or reinforcing obstacle to create an anchor for the defense or to deny the enemy decisive or key terrain (ADP 3-90). Strong points require extensive engineer support to create obstacles and increase survivability efforts. This include providing all assets overhead protection, trenches, and other protective construction using both natural and man-made terrain. Commanders prepare a strong point for all around defense. Commanders also establish a strong point when anticipating that enemy actions will isolate a defending force retaining terrain critical to the defense. A-69. Before assigning a strong point mission, commanders ensure that the strong point force has sufficient time and resources to construct the position. A minimally effective strong point typically requires one day of effort from an engineer unit the same size as the unit defending the strong point. Normally, companies and battalions occupy strong points, although brigades may construct them. Units do not normally establish strong points for units smaller than company size. This is because a platoon or squad cannot secure a perimeter large enough to contain all required assets and supplies. A-70. Units as large as battalion task forces and as small as squads or sections use BPs. Commanders select positions based on terrain, enemy capabilities, and friendly capabilities. A commander can assign all or some subordinates’ BPs within their BP. Figure A-32 depicts a combined arms battalion BP. A-71. A commander may assign subordinates BPs in situations when there is a need to retain a greater degree of control over the maneuver of subordinate units than that provided through only using an assigned area, as the higher unit controls maneuver outside the general location of the BP. A commander can assign multiple BPs to a single unit, which allows that unit to maneuver between BPs. The commander specifies mission and engagement criteria to the unit assigned to a BP. Security, functional and multifunctional support, and sustainment forces typically operate outside a unit’s BP. Figure A-33 on page A-22 depicts a brigade assigned area with battalion BPs. A-72. Units occupy or depart BPs as part of the overall plan. The commander assigning a unit to a BP should specify when and under what conditions the unit can displace from the position, since a BP is not normally held at all costs. If a higher echelon commander orders a unit to defend a BP, its commander has the option of moving off the BP. If a higher echelon commander directs a unit to retain a BP, the subordinate commander needs to know the specific conditions that need to exist before the unit can displace. Disengagement Line A-73. A disengagement line is a phase line located on identifiable terrain that, when crossed by the enemy, signals to defending elements that it is time to displace to their next position (ADP 3-90). Commanders use these lines in the delay and the defense when they want their defending units to avoid becoming decisively engaged. They establish criteria, either time or condition based, for disengagement, such as number of enemy vehicles by type, friendly losses, or enemy movement to flanking locations. They may designate multiple disengagement lines, one for each system in the defense, or if they want the unit to conduct multiple displacements. Figure A-34 depicts PL JOAN as a disengagement line. Engagement Area A-74. An engagement area is an area where the commander masses effects to contain and destroy an enemy force. This includes organic direct fire systems and supporting systems, such as close air support. The size and shape of the engagement area is determined by the relatively unobstructed intervisibility from the weapon systems in their firing positions and the maximum effective range of those system. Commanders designate EAs to cover each enemy avenue of approach into unit positions. The commander routinely subdivides their EA into smaller EAs for subordinates using one or more target reference points or by prominent terrain features. While subordinates are assigned sectors of fire, responsibility for an avenue of approach or key terrain is never split. Commanders at battalion and below typically use this control measure. The seven steps of engagement area development are: identify all likely enemy avenues of approach, determine likely enemy schemes of maneuver, determine where to kill the enemy force, plan and integrate obstacles, emplace weapon systems, plan and integrate indirect fires, and rehearse. Figure A-34 depicts a sketch of several engagement areas used within the context of a reinforced battalion task force defense. Final Protective Fire A-75. Final protective fire is an immediately available, prearranged barrier of fire designed to impede enemy movement across defensive lines or areas (JP 3-09.3). Both direct and indirect fire weapons can provide final protective fires (FPFs). A commander can only assign each firing battery or platoon a single FPF. Firing units should lay on their FPFs (or other assigned priority targets) but do not “engage” or fire them unless directed. A FPF is a priority target for an element or system, and those fire units engage that target when they are not engaged in other fire missions. When an enemy force initiates its final assault into a defensive position, the defending unit initiates its FPFs to engage enemy infantry soldiers and armored vehicles. Figure A-35 depicts an FPF to be fired by A/1-16 Field Artillery. Final Protective Line A-76. A final protective line is a selected line of fire where an enemy assault is to be checked by interlocking fire from all available weapons and obstacles. Whenever possible, units reinforce the final protective line (FPL) with protective obstacles. All company and below echelons identify their final protective lines as part of their defensive preparations. Typically, initiation of FPFs is the signal for all elements to shift fires to their assigned portion of the final protective line and spare no ammunition in repelling the enemy assault. Figure A-36 depicts a FPL. Forward Edge of the Battle Area A-77. Forward edge of the battle area is the foremost limits of a series of areas in which ground combat units are deployed to coordinate fire support, the positioning of forces, or the maneuver of units, excluding areas in which covering or screening forces are operating (JP 3-09.3). A FEBA is not a boundary, but a phase line designating the forward most point of the MBA and helps convey the commander’s intent. It marks the foremost limits of the areas in which most ground combat units deploy, excluding the areas in which security forces are operating. MBA forces can temporarily move forward of the FEBA to expedite the retrograde operations of security forces. A commander designates a FEBA to coordinate fire support and to help maneuver subordinate forces. The FEBA shows the senior commander’s planned limit for the effects of direct fires. Defending units must address this area in their scheme of maneuver and exchange information regarding tactical plans at contact points. The Army only uses a FEBA during defensive operations. Figure A-37 depicts the current FEBA and a proposed FEBA. Main Battle Area A-78. The main battle area is the area where the commander intends to deploy the bulk of their unit to defeat an attacking enemy. The bulk of a unit’s combat power is deployed in MBA. The MBA extends from the FEBA to the unit’s rear boundary. Security forces are located outside of the MBA. Sector A-79. A sector is an operational area assigned to a unit in the defense that has rear and lateral boundaries with interlocking fires (FM 3-0). By not emplacing a boundary to a unit’s front it allows them to synchronize fires better against the enemy they are facing. A sector is different from an area of operations in that instead of a forward boundary to restrict movement and fires a higher headquarters uses maneuver control measures and fire support coordination measures. Example control measures to use include things such as a battle position and a coordinated fire line. Sectors are most appropriate for any unit likely to make direct fire contact with the enemy during high-tempo defensive operations or when there is a fluid FLOT. Units assigned a sector treat areas behind the FLOT as an AO. Sectors can be further subdivided as needed into area of operations, sectors, or zones as appropriate. Any unit not expecting to be in direct fire contact with the enemy should use an area of operations or other means of terrain management. If a unit is defending in a sector and transitions to a hasty attack to exploit the enemy, they will continue to use the sector until an order can be issued that will better control the attack, which will then change it to either a zone or area of operations. Figure A-38 depicts a battalion sector for 1-66 Armor. D IRECT F IRE C ONTROL M EASURES A-80. Commanders communicate to subordinates the manner, method, and time to initiate, shift, and mass direct fires by using direct fire control measures. The commander controls unit fires to direct the engagement of enemy systems and gain the greatest effect. The commander uses IPB products and reconnaissance to determine the most advantageous way to use direct fire control measures to mass the effects on the enemy and reduce friendly fire incidents from direct fire systems. The commander must understand the characteristics of weapon systems and available munitions (such as the danger to unprotected Soldiers when tanks fire discarding sabot ammunition over their heads or near them). Direct fire control measures defined in this publication include engagement criteria, engagement priorities, sectors of fire, TRPs, and trigger line. Maneuver platoon and company publications address and go into further detail on other direct fire control measures, such as frontal, cross, or depth fire patterns and simultaneous, alternating, or observed techniques of fire. Figure A-39 on page A-26 depicts common graphical direct fire control measures. Engagement Criteria A-81. Engagement criteria are protocols that specify those circumstances for initiating engagement with an enemy force. They may be restrictive or permissive. Commanders establish engagement criteria during direct fire planning. Commanders and leaders of small tactical units use engagement criteria in conjunction with engagement priorities and other direct fire control measures to mass fires and control fire distribution. Engagement Priority A-82. Engagement priority identifies the order in which the unit engages enemy systems or functions. Commanders assign engagement priorities based on the type or level of threat at different ranges to match organic weapon systems capabilities against enemy vulnerabilities. Engagement priorities depend on situations. Commanders use engagement priorities to distribute fires rapidly and effectively. Subordinate elements can have different engagement priorities. Normally, units engage the most dangerous targets first, followed by targets in depth or specialized systems, such as engineer vehicles. Sector of Fire A-83. A sector of fire is the area assigned to a unit or weapon system in which it will engage the enemy in accordance with established engagement priorities. Battalions and smaller echelons primarily use this direct fire control measure. Each sector of fire can extend from a firing position to the maximum engagement range of the weapon, or it can be an enclosed area at a distance from the firing position. Commanders assign each subordinate unit or available weapon system a primary sector of fire and a secondary sector of fire to increase the capability of concentrating fire in certain areas. The primary sector of fire is that area in which the assigned unit, individual, or crew-served weapon is initially responsible for engaging and destroying enemy targets located in that sector based on established priorities for engagement. Fire shifts to the secondary sector on order when there are no targets in the primary sector or when the movement of another friendly element needs covering. This secondary sector of fire should correspond to another element’s primary sector of fire to obtain mutual support. Subordinate commanders may impose additional fire control measures as required. Figure A-40 depicts primary, secondary, and enclosed sectors of fire. Target Reference Point A-84. A target reference point is a predetermined point of reference, normally a permanent structure or terrain feature that can be used when describing a target location (JP 3-09.3). A target reference point (TRP) is an easily recognizable point on the ground, either natural or manmade used to initiate, distribute, and control fires. Maneuver leaders at battalion and lower echelons designate TRPs to define unit or individual sectors of fire and observation, usually within an engagement area. A TRP can also designate the center of an area where a commander plans to rapidly distribute or converge fires. Leaders designate TRPs using the standard target symbol and numbers. Once approved by the echelon fire support officer, TRPs can be designated as indirect fire targets by using the standard target symbol and target numbering identification (using two letters and four numbers). If a TRP is not also used as an indirect fire target, it is designated using numeric marking only. Figure A-41 depicts the symbol for TRP 032, a direct fire only TRP. The rest of the TRPs in the figures in this publication are both direct and indirect fire targets and are thus designated using indirect fire procedures. point 032 Trigger Line A-85. A trigger line is a phase line used to initiate and mass fires into an engagement area or an objective at a predetermined range for all or like weapon systems. Event or time-oriented criteria are used to initiate planned actions directed toward achieving surprise and inflicting maximum destruction on the enemy. Commanders can designate one trigger line for all weapon systems or separate trigger lines for each weapon or type of weapon system. Commanders specify the engagement criteria for this situation. The criteria may be either time or event driven, such as when a certain number or certain types of vehicles cross the trigger line before initiating engagement. Commanders can use a time-based fires delivery method or a geography-based fires delivery. Commanders may reserve the authority to initiate engagement by firing the commander’s own individual weapon or giving the command to fire. A-86. Commanders designate a PL as the trigger line for available supporting fire support systems. They base the location of the trigger line on the mission variables, including such variables as the time of flight for artillery shells, positioning of the guns, and the existence of quick-fire links. The trigger line’s location varies from situation to situation. Its position reflects the distance an enemy force is likely to traverse in the time it takes from when fires are requested to when artillery rounds impact at a given enemy’s movement speed. This gives time for supporting fire support systems to respond to the initial call for fire. For example, in a desert environment an enemy force is expected to travel two kilometers in three minutes. The battalion creates an indirect fire trigger line that is approximately two kilometers beyond the point where the commander wants to engage enemy forces with indirect fires since it takes three minutes to process a call for fire and for rounds to impact. Figure A-42 depicts both direct fire and fire support trigger lines based on enemy movement. A-87. Commanders can establish another trigger line for the unit’s most accurate long-range weapon system in the vicinity of the area where the fire support impacts to capitalize on the asymmetric attack. However, dust and debris resulting from the artillery fire may prevent direct fire systems from engaging enemy forces. Commanders establish other trigger lines and TRPs for shorter-range systems. Commanders may give guidance to extremely proficient crews to engage enemy forces at longer than normal ranges or give them different engagement priorities than the rest of the force, such as giving priority to engaging air defense or engineer breaching systems. A-88. As enemy forces advance, commanders establish a decision point to help force a determination on whether to continue to fire in depth or to concentrate unit fires on a single point. Many factors impact this decision, most of which concern enemy forces regarding their methods of maneuver and the effects of the defending force’s fires. COMMON FIRE SUPPORT COORDINATION MEASURES A-89. Commanders employ FSCMs to facilitate rapid target engagement and simultaneously provide safeguards for friendly forces. The fire support coordinator recommends FSCMs to the commander based on the commander’s guidance, location of friendly forces, scheme of maneuver, and anticipated enemy actions. Locations and implementing instructions for FSCMs are disseminated electronically and via overlays through command and fire support channels to higher, lower, and adjacent units. Once established, FSCMs are entered into or posted on all the command’s displays and databases. Below are some of the most commonly used FSCMs. FSCMs are either permissive or restrictive. (See ADP 3-19 and FM 3-09 for a detailed explanation on the use of all FSCMs.) P ERMISSIVE F IRE S UPPORT C OORDINATION M EASURES A-90. Permissive FSCMs facilitate the attack of surface targets. Permissive FSCMs do not include the clearance of airspace and all fires require terrain and airspace clearance prior to engagement. FSCMs will change frequently during operations and the commander adjusts FSCMs as required to keep pace with operations Common permissive FSCMs include a coordinated fire line (CFL), a fire support coordination line (FSCL), kill box, and a free-fire area (FFA). Coordinated Fire Line A-91. A coordinated fire line is a line beyond which conventional surface-to-surface direct fire and indirect fire support means may fire at any time within the boundaries of the establishing headquarters without additional coordination but does not eliminate the responsibility to coordinate the airspace required to conduct the mission (JP 3-09). The purpose of the CFL is to expedite the surface-to-surface attack of targets beyond the CFL without coordination with the ground commander in whose area the targets are located. Such fires still comply with rules of engagement and law of war targeting constraints; designation of a CFL is not authorization to fire indiscriminately into the area. Brigade combat teams or divisions usually establish a CFL although a maneuver battalion may establish one, particularly during amphibious operations. It is possible for each echelon to establish a CFL so a unit would need to be aware of the several constraints. A CFL should be placed on identifiable terrain, however, additional considerations include the limits of ground observation, the location of the initial objectives in the offense, and the requirement for maximum flexibility in both maneuver and the delivery of supporting fires. Subordinate CFLs may be consolidated by higher headquarters. Figure A-43 depicts a CFL. Fire Support Coordination Line A-92. The fire support coordination line is a fire support coordination measure established by the land or amphibious force commander to support common objectives within an area of operations, beyond which all fires must be coordinated with affected commanders prior to engagement and, short of the line, all fires must be coordinated with the establishing commander prior to engagement (JP 3-09). FSCLs facilitate the expeditious attack of surface targets of opportunity beyond the coordinating measure. The FSCL is not a boundary, the synchronization of operations on either side of the FSCL is the responsibility of the establishing commander, out to the limits of the land or amphibious force boundary. FSCLs apply to all fires of air-, land-, and sea-based weapon systems using any type of ammunition. If possible, the FSCL should follow well-defined terrain features to assist identification from the air. The joint force land component commander (JFLCC) and joint force maritime component commander (JFMCC) cannot employ fires long of the FSCL without coordination with affected commanders, and the joint force air component commander (JFACC) cannot employ fires short of the FSCL without coordination with the JFLCC or JFMCC. Supporting elements attacking targets beyond the FSCL must ensure that an attack will not produce adverse effects on, or to the rear of, the line. Short of a FSCL, all air-to-ground and surface-to-surface attack operations are controlled by the appropriate land or amphibious force commander. Coordination of attacks beyond the FSCL is especially critical to commanders of air, land, and special operations forces. Figure A-44 depicts an example FSCL. coordination line A-93. The decision on where to place or even whether to use a FSCL requires careful consideration. If used, its location is based on estimates of the situation and concept of operations. The establishment of a FSCL does not create a free-fire area (FFA) beyond the FSCL. Engagements beyond the FSCL must be consistent with the establishing commander's priorities, timing, and desired effects. Location of enemy forces, anticipated rates of movement, concept and tempo of the operation, organic weapon capabilities such as wide-area munitions, or those with delayed effects, and other factors are all considered by the commander. The establishing commander adjusts the location of the FSCL as required to keep pace with operations. A series of disseminated "on-order" FSCLs will help accelerate the coordination required. The establishing commander quickly transmits the change to higher, lower, adjacent, and supporting headquarters to ensure that appropriate controlling agencies coordinate engagement operations. Changes to the FSCL require notification of all affected forces within the AO and must allow sufficient time for these forces and/or components to incorporate the FSCL change. Current technology and collaboration tools between the elements of the joint force determine the times required for changing the FSCL. The FSCL is normally positioned closer to the forward line of own troops in the defense than in the offense; however, the exact positioning depends on the situation. Placing the FSCL at greater depths will typically require support from higher headquarters and other supporting commanders. Also, when the FSCL is positioned at greater depth, there is greater requirement for detailed coordination with the establishing commander and can slow the expeditious clearance of fires short of the FSCL. By establishing a FSCL close in, yet at sufficient depth so as to not limit high tempo maneuver, land and amphibious force commanders ease the coordination requirements for engaging targets within their assigned areas by forces not under their control, such as naval surface fire support or air interdiction. Note. During large-scale combat operations, it is likely that divisions and corps are operating as a tactical headquarters and will only provide input on proposed FSCL locations to the land component commander. Free-Fire Area A-94. A free-fire area is a specific region into which any weapon system may fire without additional coordination with the establishing headquarters (JP 3-09). Where indirect fires and aircraft share a FFA, units should establish an airspace coordination area to assist in deconflicting operations. Normally, division or higher echelon headquarters establish a FFA on identifiable terrain. Figure A-45 depicts a FFA. Kill Box A-95. A kill box is a three-dimensional permissive fire support coordination measure with an associated airspace coordinating measure used to facilitate the integration of fires (JP 3-09). It is used to facilitate integrating joint fires and coordinating associated airspace. The two types of kill boxes are blue kill box and purple kill box. A blue kill box facilitates the attack of surface targets with air-to-surface munitions without coordination with the AO commander’s headquarters. Within its boundaries a blue kill box extends from the surface to a ceiling altitude agreed upon by the requesting unit, AO commander, and airspace control authority. A purple kill box facilitates the attack of surface targets with subsurface-to-surface, surface-to-surface, and air-to-surface munitions without coordination with the AO commander’s headquarters. Within its boundaries a purple kill box extends from the surface, through an airspace coordinating measure floor to a ceiling altitude agreed upon by the requesting unit, AO commander, and airspace control authority. Figure A-46 depicts a blue kill box. Figure A-47 depicts a purple kill box. (See ATPATPArmy Techniques Publications 3-09.34/MCRP 3-31.4/NTTP 3-09.2.1/AFTTP 3-2.59 for more information on kill box planning and employment.) R ESTRICTIVE F IRE S UPPORT C OORDINATION M EASURES A-96. Restrictive fire support coordination measures prevent fires into or beyond the control measure without detailed coordination. Their primary purpose is to provide safeguards for friendly forces, noncombatants, facilities, or terrain. Restrictive FSCMs include a no-fire area (NFA), a restrictive fire area (RFA), and a restrictive fire line (RFL). Establishing a restrictive measure imposes certain requirements for specific coordination before the engagement of those targets affected by the measure. No-Fire Area A-97. A no-fire area is an area designated by the appropriate commander into which fires or their effects are prohibited (JP 3-09.3). Any echelon commander uses a no-fire area to protect independently operating elements, such as forward observers and special operations forces. A commander can also use it to protect friendly forces in the echelon support area and for humanitarian reasons, such as preventing the inadvertent engagement of dislocated civilian concentrations, or to protect sensitive areas, such as cultural monuments. Figure A-48 depicts a no-fire area. This rule has two exceptions:  The establishing headquarters may approve fires within a no-fire area on a case-by-case mission basis.  When an enemy force within a no-fire area engages a friendly force, the friendly force may engage a positively identified enemy force to defend itself. Restrictive Fire Area A-98. A restrictive fire area is a location in which specific restrictions are imposed and into which fires that exceed those restrictions will not be delivered without coordination with the establishing headquarters (JP 3-09). The purpose of the RFA is to regulate fires into an area according to the stated restrictions, such as no unguided conventional or dud-producing munitions. Maneuver battalion or larger ground forces normally establish RFAs. On occasion, a company operating independently may establish an RFA. Usually, it is located on identifiable terrain by grid or by a radius (in meters) from a center point. Commanders may depict RFA restrictions on a map or overlay, or they can reference an operation order that contains the restrictions. Figure A-49 depicts a restricted fire area. Restrictive Fire Line A-99. A restrictive fire line is a specific boundary established between converging, friendly surface forces that prohibits fires or their effects from crossing (JP 3-09). Both or only one of those converging forces may be moving. Fires and their effects can cross a RFL when the event has been coordinated with the affected force. The purpose of the line is to prevent interference between converging friendly forces, such as what occurs during a linkup operation. The next higher common commander of the converging forces establishes the RFL. Located on identifiable terrain, it is usually located closer to the stationary force—if there is one—than to the moving force. Alternatively, a commander can use an RFL to protect sensitive areas, such as cultural monuments. Figure A-50 depicts a restricted fire line. F IRE S UPPORT T ARGETS A-100. A target is an entity or object that performs a function for the threat considered for possible engagement or other action (JP 3-60). There are control measures for point targets, circular targets, rectangular targets, and linear targets. Commanders designate fire support targets using a two-letter and four-digit code established in field artillery doctrine. A-101. Commanders may choose to attack two or more targets simultaneously or sequentially. A group of targets consists of simultaneously engaging two or more targets. Commanders graphically show a group of targets by circling the targets and identifying the group with a group designator. This group designator consists of the two letters assigned to the block of target numbers assigned to a unit with a number inserted between the two letters. A series of targets consists of engaging two or more targets sequentially. A series can include individual targets or combinations of individual and group targets. Commanders show a series of targets as individual targets or groups of targets within a prescribed area. Commanders assign each series a code name or nickname. The designation of a series or group of targets does not preclude the attack of individual targets within the series or group. It also does not preclude the attack of one or more groups of targets within the series. Figure A-51 depicts the different fire support targets. COMMON AIRSPACE COORDINATING MEASURES A-102. Airspace coordinating measures are measures employed to facilitate the efficient use of airspace to accomplish missions and simultaneously provide safeguards for friendly forces (JP 3-52). Airspace coordinating measures (ACMs) are employed to facilitate the efficient use of airspace to accomplish missions and simultaneously provide safeguards for friendly forces. ACMs provide the three-dimensional description of the airspace, associated restrictions, requests for access and other applicable coordination procedures. The details of each ACM are provided in the airspace control order. Airspace elements establish ACMs to accomplish one or more functions:  Establish reserved airspace for specific airspace users.  Restrict the actions of some airspace users.  Create airspace in which units can use weapons with minimal risk of friendly fire incidents. (Friendly fire incidents include death by fratricide, injury, and property damage.)  Control actions of specific airspace users.  Require airspace users to accomplish specific actions. A-103. Paragraphs A-104 through A-112 discuss some of the common airspace coordinating measures. (See JP 3-52 for a complete listing of ACMs and their uses see.) A IR C ORRIDORS A-104. An air corridor is a restricted air route of travel specified for use by friendly aircraft established for the purpose of preventing friendly aircraft from being fired upon by friendly forces (JP 3-52). It is used to route Army aviation elements between areas such as holding areas and forward arming and refueling points. An air corridor’s altitude will not exceed the coordinating altitude prescribed in the airspace control order. There are seven specific uses of air corridors. Two examples of these uses are the minimum risk route and standard use army aircraft flight route. Minimum Risk Route A-105. A minimum risk route is a temporary air corridor of defined dimensions recommended for use by aircraft that presents the minimum known hazards to low-flying aircraft transiting the combat zone (JP 3-52). These routes are recommended by the ground commander and are used primarily for cross FLOT operations. They are established based on known threats and friendly unit locations. Aircraft executing close air support missions do not usually use these routes in the vicinity of the target area. Standard Use Army Aircraft Flight Route A-106. A standard use Army aircraft flight route is a route established below the coordination level to facilitate the movement of Army aircraft (JP 3-52). It is generally used by Army aircraft for administrative and logistic purposes. If a coordination level has been established the using authority can implement it as long as it remains below the coordination level. If no coordination level has been established the airspace control authority establishes it upon the ground commander’s request. C OORDINATING A LTITUDE A-107. A coordinating altitude is an airspace coordinating measure that uses altitude to separate users and as the transition between different airspace control elements (JP 3-52). The establishment of a coordinating altitude allows the airspace control authority to assign a volume of airspace to another airspace control organization. Army forces must be aware that any airspace user that transits or fires through an established coordinating altitude must coordinate with the appropriate airspace control agency. For example, all artillery fires that exceed the coordinating altitude must be coordinated and approved prior to execution. The coordinating altitude is normally expressed in feet above mean sea level. A-108. The joint force airspace control authority establishes the coordinating altitude, typically after consultation with the other Service components. The airspace control authority publishes the coordinating altitude as part of the airspace control order. Army forces can request adjustments to the coordinating altitude based on mission requirements for approval by the airspace control authority. Typically, the only echelon that does this is a division if has a joint air-ground integration center. Figure A-52 depicts a coordinating altitude of 13,000 feet mean sea level. coordination level C OORDINATION L EVEL A-109. A coordination level is an airspace coordinating measure below which fixed-wing aircraft by normally will not fly (JP 3-52). The coordination level and coordinating altitude are not synonymous terms. The key distinction being that a coordination level is used to separate fixed-and rotary-wing aircraft while a coordinating altitude is used to separate different airspace control elements. Additionally, a coordination level can be established with or without a coordinating altitude. Army forces recommend a coordination level, or any adjustments to an existing coordination level to the airspace control authority for approval. BCTs and above can initiate a request for a coordination level within their air defense airspace management/brigade aviation element cell or joint air-ground integration center. A coordination level is established by the airspace control authority and is reflected in the airspace control order. The coordination level is normally expressed in feet above ground level. Figure A-52 depicts a coordination level. R ESTRICTED O PERATIONS Z ONE A-110. A restricted operations zone is airspace reserved for specific activities in which the operations of one or more airspace users is restricted (JP 3-52). A restricted operations zone (ROZ) ACM has fourteen specific uses. Example uses include close air support and unmanned aircraft. Close Air Support ROZ A-111. A close air support ROZ is airspace designated for holding orbits and is used by rotary-and fixed-wing aircraft in proximity to friendly forces. This ROZ is used in support of air assets performing close air support missions in support of ground maneuver forces. When determining the appropriate ROZ size units need to consider the type of aircraft providing support and altitude limits This ROZ is requested by the applicable ground maneuver force and is established by the airspace control authority. Unmanned Aircraft ROZ A-112. An unmanned aircraft ROZ is airspace of defined dimensions created specifically for UAS operations. Generally, this airspace defines where UAS operations are conducted, and does not include en route airspace. This ROZ is only for use with UAS. Requesting units should request sufficient airspace to facilitate the requirements unique to the UAS platform such as turn radius requirements. This ROZ is requested by the applicable ground maneuver for and is established by the airspace control authority.

The tactical mission tasks in this appendix describe the results or effects commanders want to achieve—the what of a mission statement. These tasks have specific military definitions. TASKS FOR TACTICAL MISSIONS B-1. Tactical mission tasks are the “what” of a mission statement. Most of these actions and effects have associated military symbols. Staffs use them in course of action development and sketches as part of the military decision-making process. Some are also graphic control measures or obstacle effects and are used as such. See table B-1 for a list of all tactical mission tasks.

Encirclements are an outcome that can result from offensive operations to isolate and destroy enemy forces or result from a friendly force being isolated by enemy forces. This appendix provides an overview of encirclement operations and consists of the organization of forces for an encirclement, control measures, and planning and execution of encirclement operations. It also includes what to do if a unit is encircled and how to break out from an encirclement. ENCIRCLEMENT OVERVIEW C-1. Encirclement is where one force loses its freedom of maneuver because an opposing force is able to isolate it by controlling all ground lines of communications and reinforcement. A unit can conduct offensive encirclement operations designed to isolate an enemy force or they could become encircled resulting from the unit's isolation by the actions of an enemy force. Encirclements occur because combat operations involving modernized forces are likely to be chaotic, intense, and highly destructive, extending across large areas containing relatively few units as each side maneuvers against the other to obtain positional advantage. C-2. Typically, encirclements result from penetrations and envelopments, or are extensions of exploitation and pursuit operations that bypass large enemy forces in order to maintain momentum. As such, they are not a separate form of maneuver but an extension of an ongoing operation. They may be planned sequels or result from exploiting an unforeseen opportunity. They usually result from the linkup of two encircling arms conducting a double envelopment. However, they can occur in situations where an attacking unit uses a major obstacle, such as a shoreline, as a second encircling force. Although a commander may designate terrain objectives in an encirclement, isolating and destroying or defeating enemy forces are the focus. Ideally, an encirclement results in the surrender of the encircled force. This minimizes friendly force losses and resource expenditures. A key consideration prior to executing an encirclement is understanding that the encircling force is fixed and therefore unavailable for other operations until the enemy force being encircled is reduced. O RGANIZATION OF F ORCES FOR AN E NCIRCLEMENT C-3. An encirclement operation usually has at least two phases—the actual encirclement and actions taken against the isolated enemy forces. Commanders consider adjusting subordinate units’ task organizations between phases to maximize unit effectiveness in each phase. The first phase is the actual encirclement that results in the enemy force’s isolation. The organization of forces for an encirclement is similar to that of a movement to contact or an envelopment. The unit executing an encirclement organizes encircling forces into a direct pressure force and one or more encircling arms. Armored, mechanized, and motorized infantry, air assault, and airborne units are especially well suited for use as an encircling force since they have the tactical mobility to reach positions that cut enemy ground lines of communication. Bypassed and non-encircled enemy forces on the flanks and rear of advancing friendly forces require all around security. C-4. A commander should direct the encirclement effort. However, there must also be unity of command for each encircling arm. The encircling force headquarters may name one of its subordinate units as the headquarters for an encircling arm. Alternatively, that force’s headquarters may create a temporary command post from organic assets, such as its tactical command post, to control one or more arms of the encirclement. If that encircling arm has subordinate inner and outer arms, each of them also requires separate subordinate commanders. The missions and spatial orientation between the inner and outer encircling arms are sufficiently different; therefore, one force cannot act in both directions at once. Figure C-1 on page C-2 depicts an encirclement. C-5. The encirclement unit organizes only an encircling arm if there is no possibility of the encircled forces receiving relief from enemy forces outside the encirclement. If there is danger of an enemy relief force reaching the encircled enemy force, the unit organizes both an inner and outer encircling arms. The commander assigns the outer encircling arm a security mission, an offensive mission to drive away any enemy relief force, or a defensive mission to prevent the enemy relief force from making contact with the encircled enemy force. Once the encirclement is complete, these inner or outer encircling arms form a perimeter. C-6. The second phase of an encirclement operation involves actions taken against an isolated enemy force. The commander’s decision to fix, contain, or destroy isolated enemy forces affects the task organization of subordinate units, as do enemy attempts to break out from the encirclement or linkup with the encircled force. All these possible outcomes require resources in terms of units and supplies, but some require more resources than others do. If the unit’s mission is to contain or fix an isolated enemy force, the unit organizes subordinate forces for defensive action and arranges them around the enemy force’s perimeter. If the unit’s mission is to reduce or destroy that same enemy force, that unit organizes subordinate forces for offensive action. A higher echelon commander often assigns either mission to the commander of a follow and support force. C-7. Regardless of whether a commander decides to fix, contain, or destroy enemy forces, the unit conducts reconnaissance to maintain contact and monitor enemy force actions in response to the encirclement. This allows the unit to respond effectively to any enemy movement. The most effective reconnaissance combines ground, aerial, and surveillance systems to provide constant coverage and multiple assessments of enemy activities throughout the encircled area. E NCIRCLEMENT C ONTROL M EASURES C-8. As shown in figure C-2, control measures for an encirclement are similar to those of other offensive operations, especially an envelopment, but with a few additional considerations. If the encirclement unit uses both an inner and an outer encircling arm, the unit must establish a boundary between them. The unit places the boundary so that each element has enough space to accomplish their mission. The inner force requires enough space to fight a defensive battle to prevent the encircled force from breaking out. The outer force requires adequate terrain and depth in its assigned area to defeat any attempt to relieve the encircled force. C-9. The commander who controls both converging forces establishes a RFL between them. The unit may also establish a free-fire area, which encloses the area occupied by a bypassed or encircled enemy forces. The unit may also establish contact points. P LANNING AN E NCIRCLEMENT C-10. Encirclement operations may require allocating large forces and significant resources. They take a great deal of time and usually slow an advance. The encircling force maintains contact with an encircled enemy force, the following general planning considerations apply. Units—  Determine the best available assets that gain and maintain contact with enemy forces.  Keep encircled enemy forces isolated and incapable of receiving intelligence, logistics, and fire support from enemy formations outside of the encirclement.  Use reconnaissance and surveillance assets so that they know the capabilities of the encircled force and, as much as possible, its commander’s intentions.  Retain freedom of maneuver.  Control fires and fields of fire to avoid fratricide. C-11. Units apply the general planning considerations for the offense or the defense depending on the overall mission. Units plan to rotate the forces involved in reducing the encircled pocket to maintain constant pressure on the enemy. C-12. Every encircled enemy unit reacts differently. Initially, some become demoralized and cannot offer any serious resistance. Additional methods for psychologically affecting enemy personnel and reducing their mental and physical capabilities is by disrupting their sleep and rest patterns. However, if left undisturbed, most enemy units recover and attempt to break out and regain contact with their main force or attack the flank and rear of advancing friendly units. The encircling force must plan for the enemy force’s most probable reactions. C-13. If the enemy force is not reduced, and it can be resupplied or has access to considerable supply stocks, then it continues to be a serious threat to encirclement units in future operations. The encircling force must be approximately equal in size to this type of encircled force to fix or contain it. This situation occurred when German forces occupied various fortified French ports after Allied armies liberated the rest of France in 1944. Each encircled German division took approximately one Allied division to maintain its isolation. Conversely, an enemy force isolated without adequate supplies either surrenders or faces containment by considerably smaller forces. This situation occurred in Egypt during the 1973 Arab-Israeli War when an Israeli division isolated the Egyptian 3rd Army. E XECUTING AN E NCIRCLEMENT C-14. When feasible, encircling forces advance parallel to the enemy’s direction of movement. They attempt to reach key passes, bridges, and other critical points before the main enemy force reaches them. When the encircling force cannot outdistance the enemy force, it engages the enemy force’s flanks to force the enemy to fight under the most unfavorable conditions possible, ultimately in two or more directions simultaneously. Engineer units rapidly breach obstacles in the path of the encircling force. Friendly forces emplace obstacle complexes, supported by fires, to block probable avenues of escape, as they counter attempted enemy breakouts from encirclement. Units may use air assault and airborne forces to seize key passes or other critical terrain objectives to cut enemy LOCs. The encircling force completes the encirclement when it cuts all enemy ground LOCs. This generally occurs when the two arms of a double envelopment complete their linkup. C-15. Intervals in an attacking force can also occur during combat operations as the result of different rates of advance by movement formations that face different levels of enemy resistance and different terrain. An encircled enemy force attempts to discover intervals and take advantage of them as it tries to escape or breakout of the encirclement. Once the enveloping force completes the linkup that creates the encirclement, it must close these intervals as quickly as possible to prevent enemy forces from exploiting them. C-16. An enemy force may attempt to cut off an encircling force and extend its flank beyond the area of the friendly attack. If the enveloping unit attempts to outflank such a hostile extension, it may lead to the overextension of the enveloping force or to a dangerous separation of the enveloping force from support. It is usually better to take advantage of the enemy force’s extension and subsequent weakness by penetrating the thinly held front of an enemy force rather than risk the overextension of the enveloping force in an effort to outflank the enemy force’s positions completely. Alternatively, in response to the unfolding encirclement an enemy force may attempt a frontal, spoiling attack. In this case, the friendly force in contact defends itself or engages in a delaying operation, while the enveloping force continues the envelopment or moves directly toward the enemy force in a counterattack. C-17. Commanders of highly mobile forces forming the inner encircling arm may choose not to establish a continuous series of positions around an encircled enemy force. They may order subordinate forces to occupy only key terrain from which they can strike at encircled enemy forces to prevent them from concentrating forces and to isolate them further. Units who adopt this technique need to be able to detect enemy attempts to breakout and concentrate sufficient combat power against these attempts to thwart their efforts to isolate encircled enemy forces. Units of the outer encircling arms prevent additional enemy forces from reinforcing the isolated enemy force or interfering with the activities of the inner encircling arm. C-18. Once units decide to destroy encircled enemy forces, they reduce those enemy forces as rapidly as possible to free resources for use elsewhere. The reduction of an encircled enemy force continues without interruption, using the maximum concentration of forces and fires, until the encircled enemy force’s complete destruction or surrender. Units may destroy encircled enemy forces by fires or by maneuver. Reduction by Fires C-19. Reducing an encircled enemy force by fires alone is the least preferred method to destroy an enemy force. This method implies that the encircling friendly forces commander will use fire support as the primary or sole means of reducing the encircled enemy force. It includes the use of artillery, mortars, direct fires, fixed-and rotary-wing aviation (including armed UAS), and cyber and electromagnetic warfare capabilities. C-20. This method has advantages and disadvantages. An advantage is that it generally reduces the number of casualties suffered by the encircling force. Disadvantages of this method include an extensive amount of attack/delivery systems, ammunition, and time to reduce the encircled force. Additionally, fires alone might not be sufficient to force the surrender of the encircled enemy force. In most cases, reducing an encircled enemy force requires using fires and movement. Reduction by Maneuver C-21. Reduction by maneuver uses a combination of fire and ground maneuver forces to attack and destroy an encircled enemy force. In many cases the constraints of time, munitions, and availability of sufficient fires assets will lead a commander to use the reduction by fires and movement method. The four techniques for reducing an encircled enemy are squeeze, hammer and anvil, wedge, and escape route. Squeeze Technique C-22. The squeeze technique uses simultaneous, coordinated attacks on enemy forces from various directions. Following the initial encirclement, the capture or destruction of an enemy force is methodical and thorough. Units use fire and movement together in a controlled contraction of the encirclement. As an enemy’s perimeter contracts, commanders remove units from the inner perimeter and add them to the reserve depending on the terrain and other mission variables. This technique is effective against battalion-size or smaller groups of encircled enemy forces. Figure C-3 depicts the squeeze technique. C-23. The squeeze technique promotes an enemy force’s confusion and rapid dispersion of combat power and prevents an enemy commander from using the enemy’s reserves in a decisive manner. The friendly unit shapes the operation by initially concentrating on destroying enemy command nodes, air defense systems, artillery systems, and sustainment capabilities. These sustainment capabilities include any drop zones, landing zones, or airstrips available to the enemy forces that would allow them to receive support from outside the encirclement. Hammer and Anvil Technique C-24. The hammer and anvil technique employs a stationary blocking force as an anvil on one or more sides of the inner perimeter, while other elements of the encircling force use offensive action as a hammer to force the encircled enemy force against the blocking force. Either the anvil or the hammer can destroy the enemy force. Usually the hammer, as the attacking element, accomplishes this task. This technique is most effective when the blocking force is located on or to the rear of a natural terrain obstacle. On favorable terrain, units can use an airborne or air assault force as the anvil or blocking element. Figure C-4 depicts the hammer technique. Wedge Technique C-25. The wedge technique uses a unit to divide enemy forces in the pocket while the rest of the encircling force remains in place. This technique allows units to concentrate against a small portion of the encircled enemy force. However, the encircling force maintains pressure on other encircled enemy forces to prevent them from reinforcing or supporting the threatened area. The unit dividing the pocket conducts sudden and swift attacks immediately after the end of supporting preparation fires. Figure C-5 depicts the wedge technique. Escape Route Technique C-26. The escape route technique involves leaving one or more gaps in the inner encircling arm to entice enemy forces to attempt a breakout. Once an enemy force starts moving and is no longer sheltered in defensive positions, that moving enemy force is more vulnerable to acquisition, attack, and destruction. A unit using this technique should integrate military information support operations with constant offensive action to demoralize the escaping enemy force. C-27. The negative aspect of these techniques is that they require considerable forces and supplies, which are not always available. Therefore, at times the encircling force has to limit itself to less decisive measures. These include temporarily containing or fixing bypassed enemy forces until resources become available to enable the encircling force to destroy the enemy force. Continued isolation of the encircled force can only be guaranteed when the enemy force cannot strengthen its forces by inserting additional units and supplies by air. Even total, long-term isolation does not necessarily lead to decisive defeat of an encircled enemy. It is a temporary measure designed to provide additional time to the attacking force. DEFENDING ENCIRCLED C-28. Encirclement of a friendly force is likely to occur during highly mobile and fluid operations or when operating in restrictive terrain. Unit offensive actions may result in encirclement. Likewise, encirclements may occur when units employ detachments left in contact. Units anticipate becoming encircled when assigned stay-behind missions or when occupying either a strong point or a combat outpost. Units make appropriate preparations in these situations. C-29. If a unit finds itself encircled, they immediately form a perimeter defense which can evolve into defending an encirclement. If this happens, distinct tactics exist for the encircled force. An encircled force has the following options: continue to defend encircled, conduct a breakout, exfiltrate toward other friendly forces, or attack deeper into enemy-controlled territory. Once encircled, the unit’s form of maneuver depends on the senior commander’s intent and mission variables, including the—  Availability of defensible terrain.  Relative combat power of friendly and enemy forces.  Sustainment status of the encircled force and its ability to be resupplied, including the ability to treat and evacuate wounded Soldiers.  Morale and fighting capacity of the Soldiers. C-30. The senior commander in an encirclement assumes command over all encircled forces and takes immediate action to protect them. In the confusion leading to an encirclement, it may be difficult to determine what units are encircled, let alone identify the senior commander. However, the senior commander is identified within the encirclement as quickly as possible. That senior commander needs to decide quickly what assets should stay within the potential encircled pocket and what assets should leave. The senior commander immediately informs their higher echelon headquarters of the situation. Simultaneously, the senior commander directs the performance of the following tasks:  Establish security.  Re-establish a chain of command.  Establish a reserve.  Establish security elements as far forward as possible to provide early warning.  Reorganize and centralize control of all artillery.  Maintain morale.  Centralize the control of all supplies. C-31. The senior commander positions security elements as far forward as possible to reestablish contact with enemy forces and provide early warning. Vigorous patrolling begins immediately. Each unit clears its position to ensure that there are no enemy forces within the perimeter. Units use technical assets and electromagnetic warfare systems to augment local security and locate areas along the perimeter where enemy forces are deploying additional forces. C-32. The senior commander re-establishes unity of command. The senior commander reorganizes any fragmented units and places Soldiers separated from their parent units under the control of other units. The senior commander establishes a clear chain of command throughout the entire encircled force, adjusts support relationships with the encirclement, and re-establishes communications with units outside the encircled force. O RGANIZATION OF F ORCES FOR AN E NCIRCLED D EFENDER C-33. With the establishment of a perimeter defense, the commander learns about the specific capabilities and limitations of the different friendly units isolated in the encirclement. The commander uses this information to design a defense to maximize the capabilities of available forces. Forward units establish mutually supporting positions around the perimeter and in depth along principal avenues of approach. Units occupy the best available defensible terrain. It may be necessary to attack to seize key or decisive terrain to incorporate that terrain into the perimeter defense. Once a unit is given an assigned area, preparations are the same as in the defense. Figure C-6 illustrates an encircled division’s perimeter defense. Encircled units make their defensive positions as strong as possible, given time and resource constraints. The unit anticipates that enemy forces will attempt to split the defenses of the encircled force and defeat it in detail. C-34. The encircled force commander establishes a reserve that is mobile enough to react quickly to events anywhere along the perimeter. Therefore, given the availability of sufficient fuel, the unit constitutes a reserve using some of any available armored, mechanized, and Stryker units. The unit centrally positions this mobile reserve to take advantage of interior lines, which exist if the encircled force commander can maneuver the reserve or reinforce threatened positions on the perimeter faster than an enemy force can shift location or reinforce. A unit can achieve interior lines through a central position (with operations diverging from a central point) from superior lateral LOCs or greater tactical mobility. If only dismounted infantry forces are available, the unit establishes small local reserves to react to potential threats. The unit organizes a mobile anti-armor element from the best available anti-armor systems. If possible, subordinate echelons also retain reserves. C-35. While defending encircled, a unit may use the reserve to limit penetrations along the perimeter. The reserve may conduct spoiling attacks or counterattacks. The commander initiates a counterattack at the decisive moment and location as the enemy force attempts to penetrate friendly defensive positions. BREAK OUT FROM AN ENCIRCLEMENT C-36. A breakout is an operation conducted by an encircled force to regain freedom of movement or contact with friendly units (ADP 3-90). It differs from other attacks only in that a simultaneous defense in other areas of the perimeter must be maintained. A breakout is both an offensive and a defensive operation. An encircled force normally attempts to conduct breakouts when one of the following four conditions exist:  The commander directs the breakout or the breakout falls within the intent of a higher echelon commander.  The encircled force lacks sufficient relative combat power to defend itself against enemy forces attempting to reduce the encirclement.  The encircled force lacks adequate terrain available to conduct its defense.  The encircled force cannot sustain itself long enough for relief by forces from outside the encircled pocket. O RGANIZATION OF F ORCES FOR A B REAKOUT C-37. Encircled units conducting a breakout attack typically task-organize to perform rupture, follow and assume, main body, and rear guard missions. The senior commander within an encirclement organizes a reserve and a separate deception force if sufficient forces exist. Previous combat may have attired the combat power of encircled units. The commander prioritizes which ones to resource if sufficient combat power does not exist to resource each of the forces. See the applicable organization depicted in figure C-7. C-38. Normally, the commander’s first priority is to resource the force with the rupture mission. The commander typically assigns multiple missions to subordinate forces because there are typically not enough forces in the encirclement to have separate forces for each required mission. For example, the follow and assume force could receive a be-prepared mission to help extract the rear guard, a mission generally given to the reserve. Forces located outside the encirclement assist the breakout by conducting shaping operations. Above all, the encircled force maintains the momentum of the breakout attack; otherwise, it is more vulnerable to destruction than it was before the breakout attempt. C-39. The encircled force reorganizes to conduct the breakout based on available resources. Without resupply, armored, mechanized, and motorized infantry units may not be able to move all their vehicles during the breakout attack. Priority of support may be limited to the rupture force and the rear guard, with the remaining force keeping only sufficient transportation assets to move the wounded and critical assets and supplies. The breakout plan outlines the commander’s destruction criteria for equipment or supplies left behind. The unit destroys all vehicles, critical munitions, supplies, and equipment (except medical supplies) it cannot move. C-40. An encircled force attacks using the rupture force to penetrate the enemy defensive positions in at least one location. The unit produces overwhelming combat power at each breakout point. The unit assigns the rupture force, which varies in size from one-third to two-thirds of the total encircled force, the mission to penetrate the enemy force’s encircling position, widen the gap, and hold the shoulders of the gap until all other encircled forces can move through. The rupture force must have sufficient strength to penetrate the enemy force’s position. This force must use surprise, mobility, and firepower to achieve a favorable combat power ratio over the enemy force at the point of attack. C-41. Initially, the rupture force is the main effort. The attack occurs where the unit anticipates a successful rupture of the enemy force’s inner ring, which facilitates subsequent operations by enabling the unit to attack enemy units from their flanks and rear. The rupture force unit probably has additional attached assets, such as additional maneuver forces and engineers. The unit should integrate these assets to achieve the rupture. C-42. The follow and assume force follows the rupture attack and is committed to maintain the momentum of the attack and seize objectives past the rupture. After the rupture force seizes a gap in the enemy encirclement, the follow and assume force normally main effort until completing linkup operations with another friendly force. When a unit receives a follow and assume mission in a breakout, its commander must coordinate closely with the rupture force commander regarding the location of the gap, the enemy situation at the rupture point, and the enemy situation, if known, along the direction of attack past the rupture point. The commander does not assign this force supporting shaping tasks, such as clear routes and fix bypassed enemy forces, if those tasks dissipate its available combat power. If executing these support tasks is vital to the success of the breakout and resources permit, then the unit designates a separate follow and support force to perform these tasks. C-43. The main body consists of the main command post, the bulk of encircled sustainment assets, the unit’s casualties, and some functional and multifunctional support assets. It contains combat forces not required for other missions and has sufficient combat power to protect itself. The overall commander places one subordinate commander in charge of the various elements of the main body to ensure orderly movement. Typically, the main body establishes a flank security force that deploys once the main body passes through the point of penetration and performs a flank screen or guard mission for the main body. C-44. The rear guard consists of Soldiers and equipment left on the perimeter to provide protection for the rupture attack and any supporting efforts, such as deception forces. Forces left in contact must conduct a vigorous delaying operation on the perimeter so that the enemy force cannot isolate any portion of the rear guard. Under a single commander, the rear guard protects the main body from attack while it moves from the area. In addition to providing security, the rear guard deceives the enemy forces about the intentions of the encircled force, simulating its activities until the main body clears the gap. C-45. A reserve primarily aims to retain flexibility through offensive action. The unit makes every attempt to keep a small portion of the encircled force uncommitted for employment at the decisive moment to ensure the breakout’s success. The unit may be unable to establish a separate reserve force because of the need to resource either the rupture force, the follow and assume force, or the rear guard. In this event, the unit assigns and prioritizes various be-prepared missions to the follow and assume force. C-46. A successful diversion is important to the success of any breakout operation. If the diversion fails to deceive the enemy commander regarding the intentions of the encircled force, the enemy commander could direct the enemy’s full combat power at the rupture point. On the other hand, the deception force may rupture the enemy’s lines. If a rupture occurs, the diversion force commander follows the intent of the commander of the encircled force. The encircled force commander may choose to exploit the success of forces conducting a diversion, or the commander may have to disengage them for use elsewhere in the breakout attempt. C ONTROL M EASURES FOR A B REAKOUT C-47. At a minimum, units use boundaries, a LD or line of contact, a time of the attack, phase lines, an axis of advance or direction of attack, objectives, and a limit of advance to control and synchronize breakouts. Units only impose those control measures necessary to synchronize operations. P LANNING A B REAKOUT C-48. The encircled commander initiates a breakout attack as quickly as possible after encirclement by enemy forces. At this time, enemy forces are normally also somewhat disorganized, and they may not respond in a coordinated manner. Commanders should initiate a breakout attack even though detailed combat information about the enemy force’s dispositions is probably not available. The enemy force probably has not yet brought in sufficient combat power to encircle the friendly force in strength, and weak points probably exist in the enemy force’s perimeter. C-49. Early in an encirclement, there are gaps between or weaknesses in the enemy’s encircling forces. The friendly unit uses available reconnaissance and surveillance assets, including available joint systems, to provide information that increases the accuracy of the unit’s situational understanding and determines enemy weak points. The unit’s plans for the breakout attack capitalize on those identified weak points. Although the resulting attack may be along a less direct route or over less favorable terrain, it is the best COA because it avoids enemy strength and increases the chance for surprise. C-50. An encircled force may be operating under adverse conditions and may not have its normal information collection capabilities. This forces the encircled unit to conduct aggressive reconnaissance to collect information on enemy forces. The encircled unit also obtains information from joint assets, stay-behind units, and special operations forces in the area. If the enemy force is in close contact, the encircled unit may need to conduct a reconnaissance in force to ascertain enemy strengths. In any case, the unit quickly selects a COA and develops a plan accordingly. C-51. A supporting effort, such as a deception, assists a breakout by diverting enemy attention and resources away from the rupture effort. The force conducting a supporting effort may be located either inside or outside the encirclement area. The enemy force must regard the efforts of this force as credible and a threat to the continuity of the enemy force’s maneuver plan. The encircled commander directs the friendly force’s deception efforts to a point where the enemy force might expect a breakout or relief effort. The deception force is as mobile as available vehicles, fuel stocks, and trafficability allow, so it can reposition to take part in the breakout or maneuver elsewhere to support the breakout. Mobile, self-propelled weapons systems suit the needs of forces conducting supporting efforts. Additionally, the probability of a successful breakout increases measurably if another friendly force attacks toward the encircled force as it attempts to breakout. C-52. The encircled unit conducts tactical deception along with cyberspace electromagnetic activities tasks to assist the breakout attempt. Cyberspace electromagnetic activities is the process of planning, integrating, and synchronizing cyberspace operations and electromagnetic warfare operations in support of unified land operations (ADP 3-0). Tactical deception operations mislead enemy forces about the intentions of the encircled force, especially the location of the breakout attempt. For example, unmanned aircraft can concentrate their activities in an area away from where the rupture effort occurs to deceive enemy forces as to the exact location of the rupture. If it is not possible to breakout immediately, the encircled unit attempts to deceive enemy forces regarding the time and place of the breakout by concealing friendly breakout preparations and changing positions. The encircled unit can also make it appear that the encircled force will make a resolute stand and await relief. C-53. Units can use dummy radio traffic for the enemy to monitor or landlines that the enemy might be able tap to convey false information. The breakout should not be along the obvious route toward friendly lines, unless there is no other alternative. In this respect, breakout preparations mirror the preparations for any other offensive operation. As in other offensive actions, secrecy, tactical deception, and surprise allow for success. The other planning considerations for the breakout are the same as for any other attack. E XECUTING A B REAKOUT C-54. The unit exploits darkness and limited visibility during a breakout if friendly encircled forces have superior night vision capabilities. Concealment provided by darkness, fog, smoke, or severe weather conditions favor breakout by mitigating the effectiveness of the encircling enemy weapon systems or night vision devices/optics. The enemy has difficulty following the movements of the breakout force during conditions of limited visibility. However, if the encircled force waits for darkness or limited visibility, the encircling enemy may have time to consolidate containment positions. If friendly forces have air superiority, they may initiate a daylight breakout attack to exploit close air support capabilities. C-55. The encircled force takes all possible precautions to deceive the enemy force about the location of the main effort. The rupture force minimizes occupation of attack positions before starting the breakout. An encircled unit may require one or more supporting effort to assist the rupture force in penetrating enemy positions and expanding the shoulders of the rupture. The encircled unit may use feints and demonstrations to deceive enemy forces concerning the location and time of the main effort. However, deception attacks need not always occur first. C-56. The encircled commander organizes and controls the rupture force in the same manner as during an attack or movement to contact. Figure C-8 illustrates an example organization of forces for a breakout by an encircled division. The rupture force generates overwhelming combat power at the point of penetration and rapidly overwhelms enemy positions and expands the penetration. Encircled units unable to generate sufficient combat power for both the rupture force and the perimeter defense can thin their defensive perimeter in certain areas by using a detachment left in contact in conjunction with a withdrawal before executing the attack. They may also shorten the perimeter’s length, which reduces the size of the area occupied by the encircled force. C-57. The rupture force applies the breaching fundamentals of suppress, obscure, secure, reduce, and assault to ensure its success at the point of penetration. These fundamentals always apply, but their application varies based on the prevailing mission variables. C-58. The encircled commander orders the rupture force to hold the shoulders of the penetration while the follow and assume force moves forward, if enemy forces at the penetration point have roughly the same combat power as the rupture force. As depicted in figure C-9 on page C-14, the actions of the follow and assume force then become the main effort. The encircled commander may have the rupture force continue its attack if enemy forces are not strong. If there are no identified enemy forces beyond the penetration, the rupture force may transition to a movement to contact. After the encircled friendly force breaks out, it moves toward other friendly forces and links up with them. C-59. Initially, the follow and assume force passes through the gap created by the rupture force. This force continues to move rapidly from the encircled area toward its final objective. If the follow and assume force becomes the encircled unit’s main effort, it cannot allow itself to become bogged down. Preparation fires by artillery, Army aviation, close air support, and air interdiction help the follow and assume force in maintaining momentum out of the encircled area. C-60. Once the breakout attack starts, the rear guard and any deception forces disengage or delay toward the area of the rupture. Perimeter forces integrate smoothly into the rear of the breakout column. Once the breakout succeeds, the commander shifts priority of fires as required by the mission variables. C-61. As other encircled units support or move through the area of penetration, the rear-guard commander must deploy forces over an extended area. The rear guard requires flexibility and mobility. The rear guard maintains the perimeter against enemy pressure. If the enemy force succeeds in destroying or encircling the original rear guard in the breakout process, then the unit must reconstitute a new rear guard. C-62. The main body follows the follow and assume force. It moves rapidly on multiple routes in an approach march immediately behind the follow and assume force, protected on its flanks by security elements. It should contain sufficient combat power to protect itself and reinforce the flank or rear security forces if they come under attack. C-63. Normally, the rear guard initially conducts a withdrawal to break contact with the enemy forces around the perimeter. It contracts the perimeter as it delays behind the main body. If enemy forces closely pursue the breakout force, the efforts of the rear guard may become the main effort for the encircled force. The unit should position the reserve where it can also support the rear guard. C-64. Initially, the priority for fire support is with the rupture force. Those fires focus on suppressing and obscuring the point of penetration. Fire support assets move as part of the main body and rear guard so security forces have adequate fire support. Target identification difficulties resulting from proximity and intermixing of forces, as well as the rapidly changing ground situation during the execution of a breakout, make close air support difficult. C-65. Engineers with the rupture force focus on mobility operations. Engineers with the follow and assume force or the reserve improve routes as necessary. Engineers supporting flank security elements focus on conducting countermobility operations. The rear guard must also have enough engineer support to conduct countermobility operations. C-66. The senior commander prioritizes supporting AMD assets to protect the rupture force, the rear guard, and the main body. This support may come from outside the encircled perimeter. The rear guard is second in priority of protection to help prevent enemy forces targeting the main body from overrunning it. C-67. Commanders can relieve sustainment shortfalls by using aerial resupply, ordering external forces to establish support areas, and using captured supplies. All units and vehicles carry the maximum supplies possible, with emphasis on carrying petroleum, oils, and lubricants and ammunition. The encircled force only takes vehicles it can support. It may be possible for the higher echelon headquarters of the encircled force to establish an intermediate staging base as the breakout attack moves toward a linkup with other friendly forces. C ONSIDERATIONS FOR AN E NCIRCLED D EFENDER C-68. When defending an encircled area, units consider employing aviation, fires, engineer, and sustainment assets. Divisions and corps may consider relocating aviation systems from any attached combat aviation brigades to locations that are not in danger of encirclement. Aviation assets can rapidly bring additional firepower to bear on an encircling enemy force or rapidly move reaction forces to threatened locations along a defensive perimeter. Generally, aviation assets fly out of an encirclement when it becomes small enough to allow the enemy force’s artillery to range throughout the area. C-69. The commander centrally controls fire support systems, such as artillery, to provide support at numerous points along the perimeter and mass fires. The commander designates the senior field artillery staff officer, such as the chief of fires or brigade fire support officer, to control fire support. At the BCTBCTBasic combat training level, the field artillery battalion commander also advises the commander. At lower echelons, commanders may co-locate mortars from various units under centralized control, especially if there are insufficient artillery assets. C-70. Generally, engineers concentrate first on countermobility, then survivability, and then mobility. Defensive protective positions include, but are not limited to, command posts, signal nodes (and other facilities for the command and control warfighting function), critical equipment (to include sensors), supply and ammunition storage/holding areas, and other items that are likely to be targeted by enemy action. Dispersal is difficult in a perimeter type defense; therefore, the next best alternative is position hardening by constructing field fortifications. C-71. Encircled units closely monitor their sustainment assets and supply stocks, especially if they cannot be resupplied for an extended period. Leader’s conserve and centrally control available resources. A commander may force units on the perimeter to cease all vehicle movement to allocate remaining fuel assets to the reserve. The senior commander within an encirclement retains essential sustainment capabilities to sustain the defense under the control of a senior sustainment operator or commander. When possible, that commander positions these units and their assets beyond the reach of potential penetrations in protected and concealed locations. The senior commander may incorporate other sustainment units into defensive positions in depth or around key facilities. A commander may choose to augment maneuver units with non-maneuver Soldiers, although this action may affect the non-maneuver (sustainment) capabilities of the encircled force. C-72. Casualty evacuation and mortuary affairs pose challenges for an encircled force. The unit evacuates wounded from the encirclement whenever possible for humanitarian reasons. This also reduces the burden of providing long-term medical care to wounded Soldiers. C-73. Soldiers have an inherent fear of encirclement by enemy forces. Unchecked, this fear can lead to a degradation in morale and discipline. When encircled, Soldiers under the firm control of their leaders can withstand the mental strain. Discipline can disintegrate rapidly in an encirclement. Officers and noncommissioned officers must uphold the highest standards of discipline. Their personal conduct sets the example. Encircled Soldiers need to see their senior commander and other leaders frequently. Leaders at all levels need to display a calm and confident manner. Soldiers in an encirclement must not regard their situation as desperate or hopeless. Commanders and leaders at all levels maintain the confidence of Soldiers by resolute action and a positive attitude. They must keep their Soldiers informed to suppress rumors and counter enemy propaganda. This page intentionally left blank.

The glossary lists acronyms and terms with Army, multi-Service, or joint definitions, and other selected terms. Where Army and joint definitions are different, (Army) follows the term. Terms for which FM 3-90 is the proponent publication (the authority) are marked with an asterisk (*). The proponent publication for other terms is listed in parentheses after the definition.

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