The number of platforms and projectiles in the Tactical Battle Area (TBA) has increased exponentially. The friendly and adversary aerial systems are not only increasing in numbers, but are also of a variety of sizes from micro UAVs to large aircraft and they are also travelling from very slow speeds to many times faster than the speed of sound. The civil air routes are also increasing manifold and with Future Air Navigation System (FANS), the routes could be more flexible. As airspace is a finite resource, it is imperative that appropriate control is exercised for efficient operations, freedom of action, and safety to prevent fratricide. Airspace Control (ASC) refers to regulating the use of airspace by various users. From a military operations point of view, the objective of airspace control is to maximise the effectiveness of combat operations without imposing undue restrictions and with minimal adverse impact on the capabilities of any component. It is about close coordination that must exist between airspace control, Air Traffic Control and the area Air Defence units to balance the risks with the requirements for effective air defence. Detailed engagement procedures provide maximum flexibility and responsiveness.
During conflict, the air activity in the TBA is extremely dense as both friendly and enemy aircraft are transiting. Horizontal and vertical airspace is not only fully covered, but variations in time and space are dynamic. Most flights are launched at very short notice based on the evolving tactical situation. There are many Uninhabited Air Systems (UAS). Also occupying the airspace are high velocity long and medium range artillery shells and a variety of missiles. Ground-based air defence weapons are on hot standby and some operated from remote locations close to the Forward Edge of the Battle Area (FEBA). The civil air operations have to be allowed to continue albeit with some restrictions and regulations in time and space. There is, therefore, the need for faster timely information sharing. There have to be clearly designated agencies for direct and procedural control.
Unity of Control
Airspace command and control requires unity of control for the myriads of actions performed by the various military elements. It requires qualified personnel, information and a support structure to build a comprehensive picture of the battle-space. Other field elements provide planning resources. The Indian Air Force’s (IAF) tactical air elements with the Indian Army and the Indian Navy support coordination between the services. Several types of control exist that can be used exclusively or combined to achieve the desired degree of autonomy in operations. Control could be through close control of an in-flight aircraft or surface-to-air weapons unit to engage targets for specified period. Control could also be procedural.
Agencies and Individuals
Agencies and individuals that perform air control functions include the Air Defence Control Centre, Tactical Air-operations Centre (TAC) and Maritime Elements of Air Force (MEAF). They use radars and secure communications. Designated controllers and coordinators such as tactical air coordinators (airborne), assault support coordinators, forward air controllers (airborne and on ground), air traffic controllers, radar controllers, information communications technology managers, the aircraft flight leader and surface-to-air weapons units are involved.
Airspace Control Methods
Integration of the elements is most important. The control is either positive or procedural. Positive control relies on real time identification and tracking. It is conducted using radars; Identification Friend or Foe (IFF) interrogators and receivers; beacons; computers; digital data links; and communications equipment. All these facilities are vulnerable to attack and sabotage. They may be restricted by line of sight coverage, electronic interference and limited communications. They thus require back-up procedures to compensate for failure of part or all of their systems. Procedural control relies on previously agreed upon and promulgated orders and procedures; included in these orders and procedures are ASC measures, fire support coordinating measures and air defence control measures. Procedural control divides the airspace by volume and time and uses weapons control statuses to manage aviation operations. It is less vulnerable to interference by electronic and physical attack and ensures continuity of operations under adverse environmental conditions. It also serves as a backup system if positive control is lost. Usually, procedural control is implemented to cover positive control limitations.
Air Defence Layers and Engagement Options
Air Defence of a vital asset or an area is normally built around a system of concentric layers. The outer layer will usually be handled by fighter aircraft with Active Electronically Scanned Array (AESA) radars and combinations of AD missiles supported by AEW&C. If an attacker is able to penetrate this layer, then the next layer is covered by surface-to-air missiles, some with ranges in excess of 150 kilometres. The S-400 Triumf class which has a family of missiles covering different height and range bands could neutralise targets up to 400km. Other shorter range missiles would have ranges around 30km to 50km. Finally, there will be the Close-In-Weapon-System (CIWS), the Very Short Range AD System (VSHORADS) missiles, the man-portable missiles and the radar controlled anti-aircraft guns firing several thousand rounds per minute.
Surface and Airborne Radars
Ground-based, high and medium powered surveillance radars, tethered aerostat radar balloons, missile acquisition and guidance radars, tactical battlefield mobile radars and ship-based radars are all part of the ground sensor network. These radars can detect threats at various levels. Some are transportable. Many are three-dimensional and provide a panoramic picture. They have ECCM to protect against jamming. There are also over-the-horizon radars that support anti-ballistic missile operations. To cater for the stealth aircraft threat, countries are developing very long-range L, UHF and VHF wavelength radars. Air Traffic Control (ATC) radars and controllers perform a significant role in airspace management.
The Airborne Early Warning and Control (AEW&C) system is an airborne radar picket system designed to detect aircraft, ships and vehicles at long ranges and perform command and control of battle-space and air engagements by directing fighter and attack aircraft strikes. Because of its mobility, it is much less vulnerable to counter-attack, though it will be targeted by enemy fighters and missiles. There are also a large number of helicopter AEW systems.
Procedural Airspace Control
Air control points are earmarked on the ground for aircrew to route to their targets. These must be easily identified from the air and support the ground tactical plans. These are promulgated through the daily orders. Air control points can be designated separately for Entry/exit, En route, Orbit/holding, Contact point, Rendezvous, Egress control, Penetration, Ingress and Return. The procedures allow friendly aircraft to move safely throughout the TBA by utilising predictable flight paths. Inter-service aviation operations could be based by coordinating altitudes to create buffers.
Fire Support Coordination
Fire support coordinating measures allow a commander to open areas of the battle space for rapid engagement of targets or to restrict and control fires. Permissive fire support facilitates the attack on targets. Restrictive fire support measures and no-fire zones safeguard own aerial platforms. The air defence action area and the airspace above it are areas within which friendly aircraft or surface-to-air weapons are normally given preference to conduct air defence operations.
Air Defence Identification Zone (ADIZ)
An ADIZ consists of airspace of defined dimensions that require ready identification, location and control of airborne vehicles. Typically, an ADIZ is established in sovereign national boundaries or in an operational area. It minimises mutual interference between air defence and other operations. It may include one or more air defence areas, ADIZs or firepower umbrellas.
The Weapons Engagement Zone (WEZ) is the airspace within which the responsibility for engagement normally rests with a particular weapon system. These include Fighter Engagement Zones (FEZs), various types of Missile Engagement Zones (MEZs) and joint engagement zones (JEZs). The size of WEZ depends on specific weapons system capabilities. The FEZ is normally promulgated when fighter aircraft have clear operational advantage over surface-based systems. Surface-to-air missile systems will not be allowed to fire weapons into a FEZ unless targets are positively identified as hostile, identified and/or assigned by a higher authority or firing in self-defence. In MEZ, the responsibility for engagement normally rests with missiles. MEZs are divided into high-altitude and low-altitude MEZs. In a JEZ, multiple air defence weapon systems are simultaneously employed and correct differentiation between friendly, neutral, and enemy aircraft is required. The Base Air Defence Zone (BADZ) is established around an air base with short-range air defence weapon systems. Vital Area is a designated area or installation to be defended by air defence units. Vital Areas include airfields, command and control systems, signal units, GCI units and some other command elements. Emission Control (EMCON) regulates the use of electromagnetic, acoustic and other emitters to optimise command and control capabilities. EMCON also aids in executing a military deception plan.
Weapons Control and Coordination
It is an endeavour to achieve decentralised control of assets, to allow maximum flexibility to attack or counter aircraft and missile threat. Centralised control occurs when the controlling agency directs target engagements. Even during centralised control, the right of self-defence is never denied. During decentralised control, controlling agencies monitor so as to prevent simultaneous engagements of same hostile threat. Decentralised control increases the chance of engaging a hostile aircraft in a high-density environment.
Airspace Control and Air Defence
Close coordination must exist between ASC agencies. The control areas and functions must be clearly spelt out. Data-linked communications enables this process. Timely, tailored and fused situational awareness is crucial. Also, there is a need for assessment of adversary capabilities and vulnerabilities. Air defence commander is responsible for early warning, and launching Operational Readiness Platform (ORP) aircraft or diverting friendly airborne AD aircraft to take on the threat. Positive airspace control is required. Close control, broadcast, tactical or data-link control has to be provided to the Defensive Counter Air (DCA) missions and assigns targets to surface-to-air weapons units. Pre-planned air support operations, and air reconnaissance missions also require support. Operators should be able to recognise and act on electronic warfare actions using active and passive measures.
ASC is supported by radars, aircraft transponders, flight data processing systems, special software for fully automated systems and conflict alerts and algorithms for possible vectoring solution. Area penetration warning for preventing restricted area entry. Operational Data Links (ODL) allow digital messaging between platforms and ground system. Screen content recording, allows better reconstruct and post event analysis.
Air Space Control in the TBA
The airspace control order provides the details of coordination measures for the air-tasking cycle and includes fire support coordination measures, air defence areas and air traffic areas along with other airspace information. Airspace de-confliction at the operational level normally occurs within the air operations centre. De-confliction at the tactical level is handled by ATC and radar controllers. Degraded C2 environment is catered for. The air component commander must ensure that the surface commander’s listed critical assets are protected. Fire support coordination should allow commanders rapid engagement of targets. Air and surface elements must use the same geographical map reference grid. Joint networks are crucial for integration across components. Coordination with civil air operations is important during transition into or out of war-zones. Preventing collision between airborne platforms/objects is a task.
Air Space Control – Indian Scenario
In the TBA, both sides air effort tries to engage the adversary ground forces. The IAF will support the Indian Army. There will also be many joint or Special Operations. Between the Indian Armed Forces, the domains are clearly demarcated. The Indian Army manages the surface coordination, the Indian Navy manages the maritime picture and the IAF coordinates the ASC. The air defence of the nation is the IAF’s responsibility. The air defence of the Indian Army and the Indian Navy’s integral assets is their own responsibility. The big situational air picture is created by the IAF using its own, civil and radars of the other services. Such a picture is made available at the Tactical Air Control (TAC) level to the Army and at the Maritime Element of the Air Force (MEAF) level to the Navy. The air defence clearance for all air movement is given by the IAF. Very low flying army air assets within a small bubble of air space do not require any clearance, but flight information has to be digitally communicated. Similarly inter-ship naval helicopter flights are managed by the Indian Navy. All flights within the ADIZ require IAF air defence clearance.
Naval flights beyond the ADIZ are managed by the Indian Navy. IAF attack and support aircraft flying in support of the Indian Navy beyond the ADIZ are coordinated by the Indian Navy. Any hold-fire order passed by the IAF would be for short duration over a small geographical area so that full-scale operations of the Indian Army or the Indian Navy are not hampered. Low-level routing of IAF aircraft through the TBA is normally through points in joint knowledge. The IAF aircrew acting as Forward Air Controllers (FAC) also support ASC at the tactical level. There is interface between the IAF and the Indian Army at Corps HQ and Command HQ levels to iron out day-to-day issues and jointly monitor the progress of battle. Similarly, air elements operate with the Indian Navy.
To carry out the above tasks, detailed arrangements are in place at successive levels of command (Corps/Division/Brigade). The apex control of ASC is with the IAF which is the largest user of air space. The instructions for allowing or denying the use of air space to a user are laid out both as standing instructions (height bands, time slots, fly/no fly zones and more), as well as, in the form of dynamic and instant instructions applicable to a user at a point in time. The IAF is now aligning all the ASC functions through its Integrated Air Command and Control System (IACCS).
ASC and Civil Traffic
The ASC organisation also takes in its fold the civil aviation with detailed institutionalised tie up between the IAF and the Directorate General of Civil Aviation (DGCA). The Next Generation Air Transport System (NAS) will transform the current airspace and shorten air routes transferring GPS location using data-links. There have been many incidents during the Cold War and more recently near conflict zones where airliners have been shot down by air defence aircraft and missiles. Any airspace management has to ensure civil aircraft safety. Terrorists in the air are now a real threat. Terrorists are acquiring weapon-laden UAVs or surface-to-surface missiles. A terrorist has the advantage of choosing time and place of attack. While response to the threat would be conventional, air defence procedures have to be tailored to tackle possible rouge aircraft at short notice.
Space-Based Assets and Applications
Satellites in Space today support a variety of optical, Infra-Red (IR) and radar-based sensors for surveillance, mapping, communications, data networking, targeting and navigation. The dependence on space for ground operations has become phenomenal. Rivals will try to decapitate such systems. The number of satellites is increasing every day. The day is not far when hypersonic airliners will transit through near space. The line dividing space and atmosphere is thinning. This is adding a new dimension to ASC. Weaponisation of space in the form of directed-energy lasers or kamikaze satellites is a possibility. Ground-based AD and ASC use satellites for their tasks.
Connectivity and Cyber Threat
All operations are now network-centric and platforms are electronically talking to one another and sharing critical data. Situational Awareness is being created through networked sensor inputs. Each service has its own secure dedicated net. Also, there are inter-service networks for sharing common domain information. A major part of the cyber war will thus be to attack the surveillance and control systems of the adversary, which may have disastrous consequences. Cyber war does not require huge armies. It can be launched by a single operator with a simple computer. The time and place of attack can be chosen. For any ground-based air defence network and ASC to succeed, it has to defend its various elements from cyber-attacks.
Permeation of UAS and Regulatory Issues
The number of Unmanned Aerial Systems (UAS) is increasing. They are now taking on all kinds of combat roles and are a new challenge for ASC. They operate 24×7. Teaming of the manned and the unmanned vehicles is a reality. The Indian armed forces are inducting UAS in larger numbers. UAS operations have to be factored in any ASC. The problem of regulation of the UAS is another challenge. India’s Ministry of Civil Aviation has notified the new liberalised Drone Rules, 2021. UAVs have been classified according to their weight. The small ones are expected to be in visual line of sight during the day time only and operate below 200ft. Large commercial drones will be registered by the DGCA as per the International Civil Aviation Organisation (ICAO) regulations and allotted a Unique Identification Number (UIN). There will be an Unmanned Aircraft Operator Permit (UAOP). All remote pilots must undergo requisite training. Drones will have to be equipped with RFID/SIM with a return-to-home option and anti-collision lights. There are restrictions for drone operations near airports and other sensitive areas notified from time to time.
Select expressways are being cleared for landing in operations or emergencies. Networking of civil radars and ATC is already on. Military aircraft would be accorded direct routing priority. There will be height band restrictions on civil traffic during operations. There are many dual-use airfields. These have typical operational peculiarities. There are peculiar security issues for military airfields. Also, many airbases will have fully armed aircraft on Operational Readiness Platforms (ORP) for take-off at short notice. Procedures for approach and landing of a battle-damaged aircraft are considerably different. Civil aprons may be used for dispersal of IAF assets. ASC has to factor in all these peculiarities.
Artificial Intelligence in Air Space Management
Computer systems now perform many tasks that normally required human intelligence such as visual perception, speech recognition, decision-making and translation between languages. Artificial Intelligence (AI) has great scope for ASC. Intelligent machine systems can interpret complex data, perceive the environment and take appropriate action using problem-solving techniques. AI will augment human decision-making for ASC, especially during high air movement and will be more predictive to avoid potentially dangerous events. It will help Go-No-Go decisions. AI will relieve the radar and air traffic controller from the current chronic fatigue. It will greatly support the very dynamic ASC challenges and provide maximum freedom of operations.
A mix of manned-unmanned operations, including UAS swarms will be the first major ASC challenge. Intelligent onboard systems will exchange processed information with air traffic and fighter controllers over high-speed digital data links. Onboard collision avoidance and advanced traffic display systems will greatly improve the situational awareness of pilots and controllers. The ‘information-rich’ environment will require integrity and security of data. Sifting through raw data to make it meaningful dissemination, display and use, will be required. Human-computer interface will be crucial. Switching to newer technologies will have to be smooth. The air traffic and projectile density in the TBA will continue to increase. The airspace of the future will be ‘dynamic’, but the ASC will be supported by accurate navigation, height measurement and precision weapons.
Myriads of sensors will help create a very realistic day and night all-weather situational picture for the commanders and controllers to manage the airspace more efficiently. It will be possible to display a 3D dynamic picture in an underground bunker using data. AI will support quick decision making and enhance freedom of operation. The hold-fire orders will get minimised in time and space. De-confliction will be automatic and continuous in real-time. There will be need for more and more aerial platforms to be new technology compliant and have appropriate avionics and data-links. Networks will allow the control centres to be secure and placed at long distances from the fog-of-war. Technology will allow civil and military aircrew greater freedom to choose flight paths and alternative airfields even in real-time. Next generation initiatives will be more automated and flexible enough to accommodate a wide range of users. Cyber security will have to be ensured. Procedural back-ups will have to remain in place. Technologies are evolving very quickly; it is imperative for any emerging nation to move with the times.