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Procedures for A²C² are designed to specify airspace control responsibility, define the methods of accomplishing the airspace control function, ensure unity, and standardize the airspace control effort. To be effective, airspace control procedures must be sufficiently flexible and responsive to accommodate rapid changes to planned and ongoing operations.


Command and control (C²) synchronizes and coordinates combat power on the battlefield and provides the direction to fight. Command and control is defined in JCS Pub 1 as the exercise of authority and direction by a properly designated commander over assigned forces in the accomplishment of the mission. A command and control system is the means by which commanders employ forces. JCS Pub 1 defines it as a collection of facilities, equipment (to include automation), communications, procedures, and personnel essential to a commander for planning, directing, coordinating, and controlling forces and operations. Another dimension of the battlefield that the commander resources to support him in these efforts is the intelligence production process. The object of A²C² in the C² system is to support the planning process and, during the conduct of operations, link the coordination, integration, regulation, and identification tasks, present the information for decision, and timely distribute information and airspace utilization requirements to all forces.


A²C² planning is accomplished as part of the normal decision-making process. Staff functions and tasks in support of the planning process are discussed in Chapter 3 of this manual and in FM 101-5. The following points are reinforced: planning must take a forward-looking approach, the planning cycle is continuous, and the commander's intent must be understood.

The tenets of AirLand Battle dictate that staff planners follow certain considerations in developing A²C² plans. They include:

  • Limit A²C² plans and associated control measures employed to those necessary to ensure conformity with the tactical plan.

  • Make maximum use of procedural means of control. Command and control systems and voice communications provide the means to react to changes.

  • Ensure the scheme of maneuver and commander's intent determine and govern the design of the supporting plan.

  • Use airspace with maximum freedom consistent with the degree of risk that is acceptable to the commander.

  • Structure airspace control measures to facilitate recognition by either aircrews or ground-based weapons crews.

  • Where possible, ensure temporary airspace control measures (such as restricted operations zones (ROZs and HIDACZs) are encompassed by the boundaries of the level of command requesting the measure.

  • Use coordinating altitudes.

  • To enhance mission-oriented command and control for subordinate commanders, structure A²C² plans on the concept of management by exception.

  • Provide air traffic services according to the airspace control plan.

  • Devise and implement airspace control procedures for two distinct areas. These are the close and deep operations area (division rear boundary and forward to the FSCL), and the rear operations area (corps rear area and COMMZ).

The goal of A²C² planning is to identify the potential for conflicts among airspace users, and to establish the tactics, techniques, and procedures required to resolve or minimize the potential for these conflicts. These techniques and procedures are reflected in the A²C² plan. This plan may be an A²C² annex to an operation plan (OPLAN) or operation order (OPORD), or it may be an A²C² overlay with a fragmentary order (FRAGO).

Planning will be as detailed as necessary and as the situation and time allows. The urgency of the situation and the time available will dictate whether an A²C² annex is produced. In the development of an A²C² annex only that information required to clarify or amplify what is in the unit SOPs, or to specify the actions and procedures necessary to synchronize the effective use of airspace, is included. In many situations, the fast-paced and dynamic tempo of combat operations causes the A²C² staff to use an A²C² overlay and to issue verbal directives to subordinate forces.

The use of field SOPs, airspace control orders, and the airspace control plan standardizes procedures, reduces the amount of coordination, and provides implementing instructions. The need for an A²C² annex is thus minimized in many situations.


As battles are dynamic they will rarely proceed as foreseen. If the situation is altered, new decisions must be quickly formed, then coordinated and disseminated in order to synchronize subordinate and supporting actions. Once the battle is in progress the A²C² elements at the main and tactical CP continue to monitor the situations of subordinate and parent units and modify plans as required. Agility and initiative are promoted by effective coordination, rapid exchange of information, timely decision making, and rapid issue of orders.

A²C² actions required during the conduct of the battle are the same as those performed during the planning phase. The orientation during the conduct of the battle is reacting to changes in the tactical situation, anticipating future requirements based on the progress of the battle, and facilitating the ability of the commander to influence the battle by the allocation of air assets. This orientation translates into identifying potential airspace conflicts and taking immediate action to resolve the conflict. Conflict resolution is discussed in greater detail later in this chapter.

Organization of the A²C² system facilitates coordination and exchange of information and permits the A²C² elements at the tactical CP and main CP to respond to changing airspace requirements. Electronic means of communications are used in conjunction with the messenger system to disseminate information, airspace control orders, and requests for special restrictive measures. Voice, facsimile, and data systems are available to move information quickly between staff cells and command posts.

With the maneuver control system (MCS), the A²C² system has the capability, via the workstation assigned to the G3/S3 Air, to conduct the battle more effectively and timely. MCS assists the A²C² element by linking all maneuver element CPs and by integrating the AD, intelligence and EW, fire support, and CSS functional areas. MCS decision graphics provide operational data to include selected airspace control measures. Potential for growth within MCS, and fielding of automated systems for each battlefield functional area, greatly enhance near real-time airspace coordination and integration.

Airspace utilization and information displays maintained by the A²C² element within the CP include an airspace utilization and situation map and status boards and charts. Information displayed is keyed to the commander's critical information requirements.


At corps and echelons above corps (EAC), matters pertaining to the use of airspace, or the requirements of forces to use airspace, must receive prompt attention by the A²C² elements and the current operations cell. At these echelons, particularly the corps, the ability of the commander to influence the conduct of the battle is largely accomplished by the use of air assets. Because air assets can be employed in a relatively short lead time, requirements to coordinate and integrate their airspace requirements with the ongoing ground battle require immediate attention. Current operations actions at the corps (and EAC) are also required when--

  • Conflicts that require resolution develop in the corps rear area and COMMZ.

  • Corps is directing a specific operation, such as a deep operation.

  • Changes to the corps OPORD affecting the use of, or users of, the airspace are directed in response to the tactical situation.

  • Conflicts cannot be resolved at a lower echelon.

The discussion of the division A²C² element which follows is also suitable to most functions of the corps A²C² element. The division A²C² element, located at the tactical and main command post, is responsible for the A²C² function within the division's assigned area of operations. Like the corps A²C² element, it operates under the staff supervision of the G3 and conducts both future planning and current execution.

By coordinating with other staff cells within the main CP, the division A²C² element determines which combat, combat support, and CSS activities, requirements, and missions impact on effective A²C². The division A²C² element conducts planning activities and develops the appropriate plans.

The division A²C² element maintains data on ATS facilities, current and planned restrictive measures, and special joint use requirements. Conflicts that cannot be resolved per command guidance, orders, and SOP are sent to the G3 for resolution. The division A²C² element also maintains data on the AD situation, including ADA coverage for use by other tactical operations center (TOC) elements. Hostile air activity data obtained through the G2 and AD channels are provided to the division A²C² element and other elements of the division main CP. When specific details are required, information is requested from the appropriate ADA unit headquarters. The division A²C² element assists the division commander by making recommendations concerning the impact that the ADA weapons control status will have on air operations.

With the supporting ATS unit, the division A²C² element develops plans to provide ATS assistance to aircraft operating within the division area of operations and to those units conducting tactical operations. ATS units supporting the division operate under the operational control of the G3 and may be attached to the aviation brigade for logistical support.

The ATS unit supporting the division is linked with the A²C² system, the host nation ATS, and the TACS. The ATS system supports Army aircraft and aircraft of other component forces operating in the division area of operations, and divisional aviation brigade units conducting tactical operations. It also is the interface between aircraft in flight and the A²C² element at the command post. ATS support includes a broad scope of services such as navigational assistance, flight following assistance, air threat warnings, weather information, notice to airmen, artillery advisories, airfield and landing site terminal control, and other assistance as required to ensure near realtime coordination and integration of air traffic.

The division A²C² element obtains nuclear, biological, and chemical (NBC); field artillery; weather; air threat; and other air operations information that affects the control of airspace. It disseminates this information directly to the appropriate airspace users and ATS facilities.

Aircrews monitor ATS frequencies and may request flight assistance, including flight following and current information on weather, NBC, airspace restrictions, and air operations. When necessary, the division commander may direct mandatory flight following for all aircraft flights in the division rear. Flight following may be accomplished with a unit's flight operations section or with an ATS facility. Each division A²C² element maintains coordination with adjacent division A²C² elements.

Brigades and battalions focus primarily on the execution of the plan or operation. The maneuver brigade commander manages the airspace over his area of responsibility through his staff and through liaison officers (LOs) from the Air Force, Army ADA, and Army aviation. The brigade commander can form a brigade A²C² element from the ADA LO and the Army aviation LO, the brigade fire support officer (FSO), the air liaison officer (ALO), and the brigade S3 Air.

The LOs function as the brigade special staff officers for their specific functional area. They advise the brigade commander and staff on their areas and on related A²C² matters. The LOs receive information from their parent battalion TOC or from the LO at the division A²C² element.

The brigade may retain responsibility for control of battalion airspace. If not, this responsibility is assumed by the battalion staff. The maneuver battalion commander is responsible for control of airspace in the battalion area and coordinates with airspace users directly supporting battalion operations. At battalion, no special staff element is dedicated to A²C². The commander routinely coordinates with the staff, primarily the S3, who is assisted by the S3 Air, the ALO, the fire support coordinator (FSCOORD), the subordinate unit commanders, and the representatives from any supporting units (for example, an ADA platoon placed in support of the battalion). To assign responsibility, the S3 Air is designated as the principal staff executor for battalion A²C² matters.


The purpose of airspace control is to maximize the effectiveness of combat operations. Airspace control systems are established to allow all joint force members use of the airspace in order to apply timely efficient, and mutually supporting combat power. The ACA and joint force integrated airspace control system require the means to provide air traffic control services, identification, and coordination of airspace use. Accordingly such means may be in the form of positive control, procedural control, or a combination of positive and procedural control.

Positive control is a method of airspace control that uses electronic means. It relies on positive identification, tracking, and direction of aircraft within an airspace. Positive control is provided by--

  • Radar control, the continuous control of aircraft using radar and identification friend or foe (IFF)/selective identification feature (SIF) authentication procedure returns.

  • Monitoring service, the general surveillance of known air traffic movements by reference to radar scope presentations or other means.

Procedural control is a method of airspace control that relies on a combination of previously agreed on and promulgated orders and procedures. It is not accomplished by electronic means.

The precise definitions of the methods of airspace control are meaningful only when taken in the context that airspace control in the combat zone varies between the two extremes of positive and procedural. The two methods of control are fully compatible. Their relative significance at any time depends on the airspace control facilities available and the degree of threat interference. The tactical situation demands a mixture of the two methods. The Army's primary methodology is for the use of procedural control with positive control employed in those situations where such control is required and possible.

For Army purposes, positive control of assigned forces and airspace users depends on the command and control system. In airspace control, for a commander to exercise positive control, two conditions must exist:

  • Means must exist to identify and locate airspace users, and

  • Continuous communications must be maintained with airspace users.

A Guardrail mission flown by the AEB, for example, normally operates in a positive control environment. The control and reporting center, or a subordinate radar facility, provides a monitoring service to the aircraft and passes advisory information, resolves air traffic conflict, or provides navigation assistance. Two A-10 aircraft flying a CAS mission, operating within a battalion area of operation and in direct contact with the forward air controller, are integrated into the airspace through the battalion commander's A²C² cell. They are under the positive control of the air-ground operations team. Aircraft operating from an airfield in the corps area are under positive control of the ATS unit providing terminal control services at the airfield.

If positive control cannot be used, or is inappropriate to the situation, then procedural airspace control must be employed. Means of procedural control available to the A²C² element include ACOs, special instructions in the air tasking order (ATO), and ACA techniques, procedures, and rules promulgated by the airspace control plans. Airspace control annexes to OPLANS (OPORDS) and field SOPs provide additional techniques and procedures by which procedural control can be employed and executed for various situations.

Operations such as fire support, air defense artillery, tactical air, attack helicopter, and air assault have standardized operational tactics, techniques, and procedures. They provide the command and control system and the A²C² system a full scope of procedural control methods to facilitate airspace control for assigned Army forces. FM 101-5-1 provides standardized graphics used to represent the intent of the commander and to procedurally control forces.

In the example of two attack helicopter battalions conducting a deliberate attack of an armored column within a brigade's sector of operations, the commander uses standardized operational control measures. Such measures include designation of assembly areas, FARPS, axes or routes of attack phase lines, boundaries, attack positions, and engagement areas. These standardized operational measures procedurally control attack helicopters in the brigade's airspace. When the command and control system for these forces is added, commanders (through direct voice communications with all elements) are using a mix of positive and procedural measures to control airspace users.

Consider the example of a BAI force package, transiting from operating bases in the COMMZ through the corps and division areas, crossing the FLOT, en route to a target area. An interconnecting series of air routes, transit corridors, low-level transit routes, and altitude and airspeed restrictions procedurally accommodate the airspace requirements of this force. Synchronized with this BAI mission, ADA units operating within the area may have their operations largely controlled by rules and procedures established by the AADC. These procedural control measures, known as rules of engagement, when used in conjunction with weapons control status and weapons engagement zones, are also available to procedurally control airspace.


Tactical operations require the commander to employ a combination of positive and procedural methods of control. The C² system, A²C² system, and Air Force TACS provide the necessary organization and facilities to exercise positive control. Joint, Army-specific, and theater-specific airspace control measures, plus standard Army operational procedures, afford the necessary methods for the procedural control of airspace. The Army's airspace control methodology emphasizes the procedural control of airspace, particularly in the main battle area (division rear boundary and forward).


This subparagraph implements NATO STANAG 3805 (Edition Two)
and ASCC AIR STD 45/6

Airspace control measures (means) afford the commander a variety of procedural methods of controlling airspace users and airspace. Airspace control measures are the rules and mechanisms promulgated by joint and allied doctrine, and defined by the theater airspace control plan. They are defined in general terms according to the normal usage associated with the control measure. The precise dimension of various control measures (for example, low-level transit routes), and those techniques used in their arrangement and application, are specified and defined by the theater airspace control plan and ACA directives.

Airspace control measures (means) available to provide procedural control for airspace users include the following:

  • Corridors and routes:
      Air route
      Low-level transit route (LLTR)
      Minimum risk rout IMRR)
      Standard use Army aviation flight route (SAAFR)
      Special corridor
      Transit corridor
  • Zones
      Base defense zone (BDZ)
      High-density airspace control zone (HIDACZ)
      Restricted operations zone (ROZ)
      Weapons free zone (WFZ)
  • Flight levels:
      Coordinating altitude (level)
      Traverse level
  • Other airspace subdivisions or control measures:
      Airspace coordination area
      Amphibious objective area
      Terminal control area (zone)
      Weapons engagement zone
      Control point
      Time slot





Airspace control measures established by the airspace control plan may be preplanned to support various OPLANS of the joint and combined force. For example, preplanned corridors, high-density airspace control zones, base defense zones, way-points, and other control points are established to support operational requirements and anticipated changes to the tactical situation. They are assigned code names or numbers keyed to key terrain features or named areas of interest. These preplanned control measures, available on call, allow rapid adjustments to changes in the tactical situation.

When established, airspace control measures accomplish one or more of the following functions:

  • Reserve airspace for specific airspace users.

  • Restrict actions of airspace users.

  • Control actions of specific airspace

  • Require airspace users to accomplish specific actions.

Establishing airspace control measures requires the approval of the ACA. Commanders inform the ACA of their requirements for temporary airspace control measures through the appropriate airspace control system. The use of airspace request formats facilitates and standardizes the process of requesting the establishment of airspace control measures. Airspace request formats include a statement of requirements to include the location, lateral and vertical limits of the affected airspace, and time period during which the airspace restrictions apply. Appropriate remarks may be included to amplify or clarify unique operational requirements or conditions governing the use of the requested airspace. The airspace control plan describes specific procedures for requesting and activating special use airspace. The Army forwards requests through the operational chain as depicted at Figure 2-1.

The A²C² element at each command echelon reviews requests to ensure that information is complete and requested control measure(s) support the commander's concept of operations. It also determines if the activated measure will impact on other airspace users in the area of operations.

The A²C² section within the TACC's airspace control center coordinates all Army requirements for airspace control measures with the appropriate staff elements. Army liaison officers from each corps at the TACC are sources of additional information related to the corps' concept of operations. If needed, they can clarify or negotiate adjustments to requirements for airspace control measures in the corps area. Once the airspace control measure is approved by the ACA, it will be activated at the requested effective time.

Approved airspace control measures are disseminated to all appropriate elements of the joint force in accord with procedures identified in the airspace control plan. Methods for disseminating airspace control measures and other airspace control operational directives and information are discussed in Appendix B. These methods include:

  • JINTACCS, US, and NATO message formats.

  • Airspace tasking order (Section I, SPINS).

  • Airspace control order.

  • Airspace control annex, with overlay, to an operations plan or order.

Nine commonly used airspace control measures are utilized by members of the combined arms team and services. These airspace control measures and the techniques governing their use are discussed in the following paragraphs.

High-Density Airspace Control Zone. A HIDACZ (see Figure 2-2) is a defined area of airspace that is requested by the maneuver force commander, normally division and above. A HIDACZ reserves airspace and controls which airspace users have access to the zone. The HIDACZ allows the commander to restrict a volume of airspace from users not involved with his operations. The specific authority he is allowed to exercise within the HIDACZ depends on the maneuver commander's request, the situation, and the theater. By establishing the HIDACZ, the commander forces other airspace users to operate elsewhere or under the conditions and restrictions requested by the maneuver commander and imposed by the ACA. Other operations, specifically those involved in deep operations, could be adversely affected by the establishment of a HIDACZ.

The commander requests the establishment of a HIDACZ using the process previously outlined. The airspace control boundaries of the HIDACZ must fall within the area of operations (sector or zone) of a brigade, division, or covering force to allow effective command and control of operational forces. Additionally, HIDACZ airspace control boundaries, where possible, are defined in relation to appropriate geographical features to assist aviation crews and ground elements in locating and identifying HIDACZ boundaries. Combat operations during periods of limited visibility (smoke, darkness) or during poor weather may require that HIDACZ boundaries be defined in relationship to navigational aids if terrain features prove unsatisfactory.

Aircraft operations within an activated HIDACZ are governed by the procedures established by the ACA and by the operation order, operation graphics, and control measures of the appropriate commander controlling the HIDACZ. The activation of a HIDACZ at the request of a maneuver brigade commander (and approved by the division commander and ACA) within a brigade sector requires that the brigade control all airspace use within the HIDACZ. The brigade A²C² staff within the CP may serve as controlling element, or the brigade commander may request that the division attach an air traffic service's element to the brigade headquarters to assist the brigade S3 with airspace control responsibilities. The brigade's TACP is the controlling element for all Air Force operational elements which require entry into the HIDACZ.

The A²C² element of the controlling headquarters for a HIDACZ must be prepared to provide the following guidance and directions:

  • Minimum risk routing into and out of the HIDACZ, and to the target area.

  • Coordination of fire support.

  • Air traffic advisory as required.

  • Coordination of air defense weapons control status.

  • Location of enemy units.

Coordinating Altitude (Level). The coordinating altitude (level) (see Figure 2-3) is a procedural method designed to separate fixed-wing and rotary-wing aircraft. The coordinating altitude varies from theater to theater and even within a theater. The coordinating altitude does not prohibit either fixed-wing or rotary-wing aircraft in the use of airspace above or below the coordinating altitude. Aircraft that need to pass through the coordinating altitude for operational requirements coordinate with the appropriate Army or Air Force controlling agency before they penetrate the coordinating altitude. When an aircraft passes into the airspace above or below this coordinating altitude, control, either positive or procedural, always reverts to the controlling authority for that airspace.

The coordinating altitude is specified by the theater airspace control authority. Coordinating altitudes are normally specified in the airspace eontrol plan, unit SOP, or OPORD. If the Army commander requires more or less airspace to conduct his operation, he may request a change to the coordinating altitude through his A²C² element to the airspace control authority. The commander exercises care in requesting a change, especially if it increases the height of the coordinating altitude. This change may endanger all aircraft operating above the coordinating altitude in high-threat environments. The coordinating altitude also defines the upper limit of the terrain flight environment. However, this procedural control measure does not define operational control or "ownership" of airspace above or below this altitude. Some airspace control measures may eliminate the requirement for the airspace user to make notification of the penetration of the coordinating altitude.

For example, an Air Force pilot following an LLTR or other similar route is not required to make notification of passing through the coordinating altitude if the LLTR has specified altitudes established for air traffic within the route. Conversely, depending on the theater airspace control plan, Army aviation on ACA-approved Army routes above the coordinating altitude, or on an approved flight plan, may not be required to make notification of passing through the coordinating altitude.

Coordinating altitudes do not apply to air defense artillery or field artillery operations. Coordinating altitudes may be higher during hours of darkness and within the corps area and COMMZ than in the division area and forward. During low-intensity conflict operations, when the primary threat to aircraft is ground-based direct-fire weapons, the coordinating altitude may be established at higher altitudes.

Restricted Operations Zone. The terms airspace restricted area and ROZ are synonymous. A ROZ (see Figure 2-4) is a volume of airspace of defined dimensions developed for a specific operational mission or requirement. A ROZ procedurally restricts some or all airspace users from this area until the end of the mission. A ROZ is normally activated to support drop zones, search and rescue operations, SEMA orbits, and RPV launch and recovery sites. Additionally, a ROZ may facilitate air defense operations in a given area by preventing friendly aircraft from entering a volume of airspace. The commander requiring a ROZ sends his request through the appropriate A²C² facility to the airspace control authority using those procedures previously outlined. The airspace control authority coordinates requirements for temporary restricted operations zones and considers the impact of such restrictions on other airspace users.

Before using a ROZ, the commander considers its impact on the freedom of action of others and weighs that impact against its advantages. For example, a ROZ (or a HIDACZ) that is too large may make it impossible for aircraft to get to certain target areas. Controlling authority requirements for the ROZ are similar to those required for a HIDACZ. For further information on controlling authority requirements, see Designation of Controlling Authorities. Normally, the requesting commander is the controlling authority.

Minimum Risk Route. An MRR is a temporary route of flight recommended for Air Force use which presents the minimum known hazards to low-flying aircraft transiting the combat zone. It normally extends from the air route structure in COMMZ through the Army, corps, and division area, across the FLOT, and terminates in the vicinity of the FSCL. In common practice the term MRR is synonymous with the term low-level transit route. These titles are used interchangeably because these two temporary routes are defined similarly and are employed in the same manner. To achieve standardization with international agreements, this FM utilizes the term low-level transit route.

Low-Level Transit Route. An LLTR (see Figure 2-5)is a temporary corridor of defined dimensions which allows the low-level passage of friendly aircraft through friendly air defenses and controlled or restricted airspace. The ACA specifies the number of LLTRs (active and on-call) to be established to accommodate air operations. The actual trace on the ground which the LLTR follows is nominated by the divisions and corps and planned by the A²C² element with Air Force coordination and assistance. The routing accommodates transiting aircraft while avoiding critical areas and assets defended by ADA, and areas of anticipated intense combat operations (for example, axis of main attack). Additionally, airspace planners establish the corridor (route) trace to avoid such areas as--

  • Concentrations of field artillery units.

  • Significant groups of fire support targets.

  • Landing zones, drop zones, forward arming and refueling points,landing sites, and airfields.

  • Known enemy air defense artillery systems.

  • Other planned or active special use airspace (for example, ROZs, HIDACZs, special corridors).

The exact dimensions, and the techniques for employing LLTRs, are governed by the theater airspace control plan and included in unit SOPs. LLTRs are normally bidirectional and activated for short periods of time. To prevent enemy forces from exploiting an LLTR, routes are activated for specified times only and changed frequently. LLTRs normally have their start points and terminating points designated by an air control point. Air control points also designate where the corridor joins other corridors or changes direction. Points may be easily identifiable terrain features or electronic navigational aids, preplanned at random throughout the area of operations and assigned code names or numbers. Such techniques aid in restructuring LLTRs to accommodate changing tactical situations.

Airspace planners at corps and division anticipate requirements for LLTRs to support planned combat operations. Following the allocation of air assets to support Army requirements, corps and division know how many sorties are available for CAS, AI (including BAI), tactical air reconnaissance and offensive counterair. Accordingly, airspace planners should be able to anticipate the number of corridors required and, generally, which corps and division areas the corridors must transit to support the allocated sorties and Army plans for air support.

LLTRs may be established for different air missions. Air Force aircraft conducting air missions such as interdiction, tactical air reconnaissance, and offensive counterair may use a separate LLTR than aircraft supporting intratheater airlift and CAS. LLTRs require air defense weapons in the corridor, or with a sector of fire which includes the corridor, to be placed in a weapons control status of weapons tight.

Standard Use Army Aircraft Flight Route. A SAAFR (see Figure 2-6) is a route established below the coordinating altitude to facilitate the movement of Army aviation assets. Normally located in the corps and division rear area of operations, it is a recognized Army airspace control measure that does not require joint approval. SAAFRs are developed by the A²C² element to safely route Army helicopters conducting combat support and combat service support missions in the terrain flight environment. They are primarily intended for single aircraft or for small flights of aircraft operating routinely between base clusters in the division support area and in the corps rear area. Their establishment is similar to the techniques used for LLTRs, except SAAFRs do not require ACA approval.

Routes in the division rear area should provide terrain masking from enemy air defense systems to avoid compromising the SAAFR structure and key base cluster facilities. Air control points, or communication check points, assist in defining the routing and control of helicopters. Aircraft using SAAFR monitor the appropriate ATS facilities. Extending a SAAFR to the brigade support area should be considered if numerous logistic missions will be flown into the brigade support area/forward support battalion. If numerous aviation missions are expected to cross division lateral boundaries, SAAFRs can be used to procedurally control such movement.

The corps A²C² element is responsible for developing the SAAFR structure for the corps rear area and ensuring that the corps structure links to its subordinate division's SAAFR structure. The corps A²C² element also ensures that adjacent division rear area structures are linked. Division A²C² elements develop their own rear area structure.

Brigade A²C² elements must specify the termination points in each forward brigade. If a SAAFR is required between adjacent brigades, the division A²C² element is responsible for developing the required route. Terrain flight tactics and techniques are normally employed by helicopters using these routes.

Base Defense Zone and Weapons Free Zone. These are airspace procedural control measures employed in some theaters. A BDZ (see Figure 2-7) is an air defense zone established around an air base and limited to the engagement envelope of the short-range air defense (SHORAD) weapon system defending that base. Theater army aviation elements, such as the theater aviation group operating in the Army area and COMMZ, may encounter these control measures during airlift operations. BDZs have specified entry, exit, and IFF procedures which aircrews must follow. Airspace control plans provide necessary information for flight planning.

A WFZ (see Figure 2-7) is an air defense zone established for the protection of key assets or facilities of the joint force other within a WFZ are normally maintained at a weapons control status of weapons free. Aircrews must avoid active WFZs, or coordinate with the designated control authority prior to entry or prior to transit through a WFZ.

Air Corridor. An air corridor (see Figure 2-8) is a restricted air route of travel specified for use by friendly Army aircraft and established to prevent friendly forces from firing on friendly aircraft. Air corridors are standard Army operational procedures. They do not require ACA approval as they are employed within the terrain flight environment, normally in the division area of operations and the deep operations area. Air corridors are temporary in nature, established as required to route combat elements of the division and corps aviation brigade between such areas as assembly areas, holding areas, battle positions, FARPs, and target engagement areas.

Air corridors are employed as control measures during air assault operations to designate routes for air assault forces during the air movement phase. They can be used to route helicopters conducting air movement operations within the corps and division rear areas. Standard operational measures used with air corridors include: air control points, communications check points, magnetic azimuths of the routes of flight, pick-up zones, landing zones, and initial points. The ground trace of an air route is selected by the aviation liaison officer in coordination with the A²C² element and depicted graphically in the operation order overlay. Terrain, enemy air defenses, and ground maneuver plans are key factors that influence the need for and location of air corridors. An Army air corridor should not be confused with an air route. The Army air corridor is a standard Army control measure while an air route is an airspace procedural control measure normally employed in the COMMZ and corps rear area to support the movement of Air Force and host nation air traffic.

Additional Measures. Additional operational measures routinely used to assist in controlling and resolving conflicts of airspace users include selected fire support coordination measures, air defense artillery supplementary fire control measures, and air control measures. Examples of these measures include the following:

  • Airspace coordination area,

  • Fire support coordination line,

  • Weapons engagement zone,

  • Air control point,

  • Communications check point,

  • Initial point, and

  • Way-point.


Commanders, staffs, and airspace users utilize an array of standardized control measures to assign responsibility, ensure conformity with the tactical plan, describe and illustrate the concept, maintain separation of forces, concentrate effort, coordinate fires with maneuver, and assist in the command and control of forces. When airspace procedural control measures are incorporated with these standard operational measures, Army forces have the means to graphically depict the integration, coordination, regulation, and identification of Army airspace users in a given area of operations. FM 101-5-1, combined arms manuals such as FM 71-100 and FM 71-3, and functional manuals such as FM 44-1 and FM 6-20 provide further guidance pertaining to applying these operational procedures in various tactical operations.

The Army relies upon procedural control as the primary means of synchronizing airspace users in the main battle area. The Army's methodology for airspace control in this area is based on the use of coordinating altitude, standard operational procedures and graphics, fire support coordination measures, and air defense rules of engagement (see Figure 2-9).

Standard operational procedures and graphics control maneuver in the area of operations. For the vertical dimension of the area of operations, Army aircraft, except for SEMA, operate largely in the terrain flight environment below the coordinating altitude. Accordingly, as with other maneuver elements, standard operational procedures provide the most effective control techniques for this environment. Fire support coordination measures ensure that fire support systems interface and that fires do not jeopardize troop safety or disrupt adjacent unit operations. Air defense rules of engagement, chiefly hostile criteria, weapons control status, and weapons engagement zones, ensure identification and control of airspace users. Joint airspace procedural control measures are used only as required to supplement Army control measures and to facilitate the employment of joint forces in the airspace. The decision to use such measures is based on a case-by-case evaluation, using the factors of METT-T and duly considering the requirements of other service components.

Army command and control systems, specifically those of the major functional areas of maneuver (MCS), fire support (AFATDS), and air defense (FAAD C²) provide an important adjunct to the use of procedural control.

  • Supports air-land battle C².

  • Minimizes requirements for ACA approval.

  • Assures conformity with the tactical plan.

  • Prevents interference among units.

  • Describes and illustrates the concept.

  • Adds flexibility.

  • Allows for maximum freedom of action of supporting forces.

  • Is responsive to the commander.

  • Selected airspace control measures.*
      Coordinating altitude
      Standards use Army flight routes
      Others as required

  • Standard operational procedures and tactics.
      Control and coordination measures Graphics

  • Fire support coordination measures.

  • Air defense rules of engagement and
    control measures.
      Hostile criteria
      Weapons control status
      Weapons engagement areas

  • C² system provides adjunct.

*Use of theater airspace control measures is based on consideration of time required to put into effect, restrictions on other users, and airspace controlling authority responsibilities.


Determining the exact combination and type of operational procedure, fire support coordination measure, air defense procedural control technique, airspace procedural control measure, or positive control means required to synchronize airspace users and activities in a given tactical operation is a key part of the A²C² process. Representatives of the A²C² element at each command echelon, with expertise in their respective branches and functional areas, perform this A²C² activity.


During the planning process the A²C² staff identifies potential airspace conflicts among the various airspace users. It then establishes appropriate procedures to resolve the conflict or reduce the risk. During the analysis of situation and concept of operations, the focus is directed to the scheme of maneuver, plan for fires, and counterair operations. This focus is upon the use of airspace by the members of the combined arms team conducting combat, combat support, or combat service support tasks. Early in the planning phase, the A²C² staff reviews supporting plans, overlays, and graphics and sketches that depict and illustrate maneuver, fires, air defense, reconnaissance and surveillance, EW, and sustainment operations. This review identifies geographically where the intended actions of two or more airspace users, or other combatants, come into contact, or are in close proximity. These are the areas of potential airspace conflict.

Each potential conflict is then further evaluated by looking at the altitude and time. If the airspace users involved have an altitude separation that is determined to be sufficient to provide adequate safety, then a conflict does not exist. If the airspace users are operating at the same altitude, the evaluation process must continue. If the airspace users are separated by time, then a conflict does not exist. However, if the airspace users are conducting operations at the same time, then a potential for conflict exists.

To resolve each identified airspace conflict, the A²C² element selects one or more of the following options:

  • Establish procedural control employing standard operational procedures.

  • Change the time sequence, or relocate the airspace user or another element.

  • Establish an airspace procedural control measure.

  • Eliminate an airspace user, or restrict the operation of an airspace user.

  • Make the decision to accept the risk.

The A²C² element first selects the appropriate means of ensuring conformity with the tactical plan, preventing interference among units, and synchronizing the effective use of airspace. It then ensures these means are established and communicated to and coordinated with all members of the combined arms team. Map overlays, operation overlays and sketches, coordinating instructions, and annexes to operation orders (plans) are the means of illustrating and communicating the required control measures.

There may be situations in which conflicts between airspace users or requirements for the use of airspace cannot be resolved at a particular echelon. The conflict is then forwarded through operational channels to the A²C² element of the next higher headquarter for resolution. Conflicts involving only Army forces are normally resolved at division or corps level. Conflicts involving joint and combined forces may have to be resolved between the LCC and ACC at the airspace coordination center within the TACC. Normally, coordination and negotiations between the A²C² section of the BCE and the staff of the airspace management element in the combat plans division result in a satisfactory solution. Major airspace control conflicts which cannot be resolved at the LCC and ACC levels are referred to the Joint Operations Center (JOC) at the Joint Force headquarters for resolution. Examples of conflict and potential conflict resolutions include:

  • An LLTR positioned over a fire support unit(s). If a single fire support unit is involved, move the unit or accept the risk. If multiple fire support units are involved, move the LLTR.

  • A SAAFR crossing an LLTR. Develop procedures to cross the LLTR or accept the risk.

  • A FARP or aviation unit located in front of a fire support unit/ADA unit that is in a weapons free control status or located in such a manner that aircraft overfly the fire support or ADA unit. Move the FARP or move the unit. If an AD unit, place the unit on weapons tight.

  • An air control point and an AD unit in weapons free control status both located in the same area. Move the air control point or the AD unit or put the AD system on weapons tight (if appropriate).

  • An air assault/movement operation overflying AD or fire support weapon systems that is in a weapons free control status (going and, or returning). If moving all systems is impractical, place all AD systems in or near the route on weapons tight during the outbound and inbound flight times. Cease fire on all fire support weapon systems during the flight times. Exercise positive C² over the AD or fire support weapon systems. Any combination of the above options may be used.

  • An airdrop operation being conducted without restricting other air traffic from the area. Establish a ROZ over the drop zone.

  • A major ground battle projected for a specific area. The commander expects the battle to be his decisive fight and he will be required to use all of his assets in the area without interference. Create a HIDACZ over the battle area.


A²C² actions taken during the planning cycle are one aspect of the A²C² process. Reacting to changes in the tactical situation during the conduct of the battle requires similar A²C² actions. During the execution of tactical missions, changes in missions are received, the situation is evaluated, and requirements for airspace and potential conflicts between airspace users are identified. Then options are selected, coordinated, and implemented to resolve the conflicts and synchronize forces.

For example, during the conduct of a successful defensive mission, the division has issued a fragmentary order (FRAGO) to the aviation brigade directing the brigade to conduct a hasty attack against an enemy uncommitted reserve force. The A²C² staff element within the brigade, in concert with the division A²C² element, begins to monitor development of the proposed scheme of maneuver and supporting plan for fires. Operational measures to support the scheme of maneuver are compared with those of supporting air force elements. Routing of CAS aircraft is plotted; contact points, initial points, pop-up points, and other airspace control measures are established and coordinated as required. Fire support plans, priorities, targets, fire support coordination measures, and artillery unit locations are reviewed and coordinated with all appropriate forces. Air defense artillery unit locations, sectors of fire, weapons control status, and identification procedures are reviewed and coordinated and changes directed as required. Sustainment plans, such as aerial movement of class III and V products to FARPs, are reviewed; the routing of aircraft conducting logistical support missions is coordinated with other operational plans.

Special air traffic service support requirements are identified and requirements coordinated. Command, control, and communications requirements unique to the synchronization of airspace are established. One such requirement is designation of the communications net and element that will serve as the control authority for any airspace control measures established.

The difference between A²C² actions taken during the planning cycle and those performed during the conduct of operations is in the time available to establish selected control measures through the ACA and to coordinate and disseminate information. The use of positive means of control allows rapid response to changes and may be the only option in some situations. For example, greater reliance on positive control techniques and procedures is necessary during the execution of a joint air attack team (JAAT) mission. Direct communications and personal observation of the target area and friendly forces are required by the FAC, CAS flight leader, attack helicopter commander, and field artillery air observer in order to synchronize all elements of combat power. The employment of CAS normally relies on a high degree of positive control techniques and procedures because of the proximity of friendly forces and the target.

The Army air-ground operations system is structured to interface with the tactical air control system and this joint system provides the means to provide positive control of CAS missions.


One aspect of procedural control which commanders and the A²C² staff must consider concerns the responsibility to serve as the controlling authority for designated temporary airspace control measures. The approval to establish a HIDACZ or ROZ within a division area of operations requires the designation of a controlling authority for that airspace.

To serve as the controlling authority for a ROZ or HIDACZ, the establishing organization must be able to communicate with all airspace users. There are three basic options to fulfill this requirement for Army airspace users:

(1) Use an existing radio network. The advantage of this option is that the necessary radios, frequencies, and existing personnel are in place. If a brigade is the controlling authority, use of the command net may be the best solution. At corps/ division, the G3 or A²C² element operating on an existing radio network may be suitable. The disadvantage is that the radio network being used may be overburdened by the control requirement and not support passage of time-sensitive information.

(2) Create a new radio network. This option eliminates the disadvantage of the first option. However, obtaining the radios, frequencies, and personnel to accomplish this mission may be difficult.

(3) Utilize ATS facilities (FOC or flight coordination center (FCC) or special task-organized mobile tactical teams. Mobile tactical teams collocated with a brigade A²C² element provide an organization which can perform controlling authority responsibilities.

Control of Air Force airspace users by the controlling authority requires special considerations. Air Force assets provide the best means of controlling Air Force assets; however, Army ATS facilities have the necessary communications systems and can be used. Key elements of the TACS which offer the organization and material to assist the designated Army organization perform controlling authority functions are the corps ASOC, and the TACP at division and maneuver brigade levels. The collocation and continuous interface between the corps ASOC and A²C² element, and between the division and brigade TACP and their respective A²C² elements, ensure rapid coordination and sharing of information.

The airspace control request forwarded to the ACA to establish the temporary airspace control measures includes information concerning what organization will be designated the controlling authority. This information is included in the ACO, thereby giving potential airspace users the identity of the controlling authority.


Remotely piloted vehicles, special electronic mission aircraft flights, and heliborne electronic warfare flights have special requirements for airspace above the coordinating altitude. These special airspace users utilize airspace control measures, require a mix of positive and procedural controls, and must interface with the combined arms team and the Tactical Air Force.


These flights require airspace conflict resolution, establishment of necessary control measures, and coordination of missions with the Tactical Air Force. Airspace conflict resolution is accomplished by separating in time and altitude, and by sector (zone), the RPV from other aerial platforms and missions. Establishing airspace control measures provides the procedural control to ensure conflicts are reduced.

Airspace procedural control measures such as ROZs and special corridors can be employed. ROZs support RPV launch and recovery sites and large mission areas; special corridors are useful for RPV flights in a narrow corridor (route). A ROZ in the vicinity of the FLOT and extending forward to the FSCL can restrict tactical air operations. This situation may cause air force missions to weigh the risk and request clearance from the controlling authority to transit through the RPV ROZ using the principle of see-and-avoid. The airspace control authority may require that RPV mission areas be noted in the air tasking order, thus eliminating the need for airspace control measures.

Positive control, to a limited degree, can be established for those RPVs under direct control of a RPV forward control station. Communications between the control station, A²C² element, fire support personnel, and FAC permit the integration of the RPV mission with other airspace users.

Timely dissemination of information concerning RPV operations to TACS elements is accomplished through the A²C² system (see Figure 2-10). RPV operational information coordinated with other airspace users includes--

  • Location of CLRS elements, and the altitude and radius around the launch site which must be avoided.

  • Flight times.

  • Operational altitudes (flight profile).

  • Ingress and egress routes from the CLRS to the FCS hand-off point.

  • Area (route) of the intended flight.


These flights require airspace conflict resolution, establishment of control means coordination of information, and interface with the appropriate elements of the integrated airspace control system. Airspace required to accommodate typical flight profiles is significant. Normally a ROZ provides the airspace control measures to support the operational requirements of a SEMA mission.

To establish a restricted operations zone, an airspace request is submitted to the airspace control authority for approval. This airspace request is submitted through the airspace coordination channels of the corps A²C² system to the A²C² section of the BCE. This section submits the request to the airspace control center of the TACC for approval. When approved, the airspace control center will include the designated restricted operations zone in the airspace control order which is disseminated throughout the integrated airspace control system. (See Figure 2-11.)

In addition to obtaining the required airspace to support SEMA flights, a sequence of coordination actions must be accomplished. When the corps tasks the AEB to conduct an EW or surveillance mission, the flight operations element and crew of the aviation company supporting the mission conduct the necessary flight planning and submit the request for airspace as previously described. Other information related to the scheduled mission is disseminated and coordinated through the corps A²C² system and the theater integrated airspace control system. The SEMA mission may be reflected in the air component commander's ATO. The dissemination of the ATO ensures that all users of the airspace have pertinent information relevant to the SEMA mission thus ensuring safety and mutual operational efficiency.

Having the SEMA mission listed in the ATO is one option to achieve advanced airspace coordination. Another course of action might be required when time is not available to get into the ATO and ACO planning cycle. For example, in response to a SEMA mission tasking, the aviation company flight operations section and aircraft crew file a flight plan with an appropriate corps air traffic services unit (FOC or FCC) and notify the corps A²C² element. When the aircraft takes off, the pilot opens the flight plan by contacting the FOC or FCC and continues to monitor the designated FOC frequency until directed otherwise. Penetration of the coordinating altitude requires coordination only among the appropriate airspace control elements and users; it does not imply that prior approval must be obtained.

The FOC contacts the control and reporting center and passes all required information related to the SEMA mission. If operational requirements require positive control of the SEMA mission by the control and reporting center, the aircraft may be directed to maintain radio contact. This positive control link permits other tactical air force elements to transit safely through the ROZ in proximity to the Army aircraft. It also allows the CRC to pass threat warnings in near real-time.


Restricted operations zones to support heliborne EW missions are established with approval of the ACA. The request procedures and coordination required are similar to the actions described for SEMA airspace. In addition to the airspace control measures required by the heliborne EW system, EW operations must be synchronized with operational plans of both the combined arms team and the Tactical Air Force.


To effectively integrate friendly air assets and air operations with air defense operations and combined arms team weapons employment, the airspace control function must closely conform with joint force air defense operations. Effective performance of the active air defense mission requires a capability to correctly identify aircraft commensurate with the ability of the air defense system and combined arms team to employ their weapons under the most optimum conditions. This requirement is particularly acute in those theaters where large numbers of friendly aircraft and enemy aircraft are part of the tactical air environment (for example, NATO Central Region), and where air defense and combined arms team weapons are employed in conditions or at ranges beyond which positive visual identification can be performed.

Airspace control measures and the A²C² system must complement and support the air defense identification requirement. This ensures timely engagement of enemy aircraft, conserves air defense assets, and reduces risk to friendly forces. Through airspace control methods, air defense weapons systems or other combined arms team members can identify aircraft as friendly or hostile without unduly restricting friendly air maneuver or their ability to engage hostile aircraft. The A²C² system, in concert with the C² system, provides sufficient information to all airspace users and air defense and combined arms team organizations to facilitate IFF.

Identifying air assets in the forward combat zone and terrain flight environment is difficult. Identification largely depends on a mix of procedural and positive control measures. Minimum risk procedures and practices afforded by selected airspace control measures are procedural and complement visual identification and IFF/SIF procedures, the primary positive means of identification.

Army forces employ standard operational procedures, ADA rules of engagement and control measures, indirect information (such as flight plans, OPORDs, and other intelligence data), selected airspace control measures, and IFF/SIF procedures to assist in the identification process. C² systems such as the FAAD C²I, the MCS, and the A²C² system coordinate, process, disseminate, and facilitate identification requirements. The following planning factors can assist in the identification requirement during the conduct of combat operations:

  • Coordination between air and ground units, particularly ADA units.

  • Establishment of passage points and crossing times by the aviation unit and ground maneuver unit.

  • Use of both verbal and nonverbal recognition signals, particularly at night.

  • Coordination of routes to and from the area of operations. The establishment of SAAFRs, special corridors, air control points, and communication check points will aid in control and identification.

  • Inclusion of IFF/SIF codes and procedures.

  • Coordination of hostile criteria, weapons control status, and weapons engagement zones.

  • Use of flight plans, and flight following by assets operating above the coordinating altitude.

  • Coordination and standardization of identification procedures with allied and host nation force capabilities.

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