The Airports Authority of India (AAI) caters to close to 345 million air passengers per year, operating a fleet of about 620 aircraft through 103 airports. In a bid to serve the burgeoning demand, the authority has laid great emphasis on developing communication, navigation and surveillance (CNS) infrastructure in the country. AAI provides air navigation services for over 2.8 million square nautical miles (NM) of air space, comprising Indian land mass spanning 1.05 million square NM and oceanic airspace spanning 1.75 million square NM. AAI’s present air traffic management (ATM) system has been focusing on voice communication, ground-based navigation, radar surveillance, non-optimum airspace structure and aeronautical information services. CNS or ATM infrastructure deployed by AAI includes networks of various frequencies and air/ground data links on the communications front, landing aids and en route/satellite navigation systems such as the GPS Aided GEO Augmented Navigation (GAGAN) system and GBAS, surveillance systems including primary/secondary radars, and automation systems including situational awareness systems, data processing systems, controller tools, safety alerts and flow management systems for capacity optimisation at airports. Going forward, the authority aims to enhance its focus on ensuring routine communications, satellite-based navigation, complete surveillance through sensors, airspace harmonisation, aeronautical information management and centralised air traffic flow management.
Focus on new technology
AAI has laid emphasis on providing reliable and efficient ground-based equipment and adopting satellite-based communication, navigation and surveillance systems. It is planning to implement space-based ADS-B systems for surveillance over the oceanic airspace. Under the system, satellites will pick up ADS-B signals from the aircraft and the data will then be sent to the ground facility, which in turn will transmit it to the controller’s display. The system is designed to work on both land and oceanic spaces. Presently, it is being tested by Mumbai and Chennai air traffic controllers and is expected to be operationalised within the next two years. AAI also plans to increase the capacity of routes over the oceanic region in the near future.
International Civil Aviation Organization (ICAO) member states have endorsed the global satellite navigation system as the primary future navigation system for aviation and India has been taking proactive steps to ensure its implementation in the Indian airspace. GAGAN is a space-based augmentation system that has been put in place by AAI to provide satellite-based air navigation services. It is India’s first navigation system jointly developed and commissioned by AAI and the Indian Space Research Organisation and is in line with the ICAO framework for the global navigation plan. It provides the required accuracy for navigation parameters to be used for aircraft and is also interoperable with other SBAS systems like WAAS, EGNOSS and MSAS. GAGAN has been certified for approach with vertical guidance with effect from April 21, 2015. Presently, the Directorate General of Civil Aviation (DGCA) has certified it for RNP 0.1 and APV-I services. However, AAI is yet to use it to its full potential and has been taking steps to fast-track the complete implementation of GAGAN in the Indian aviation industry.
Besides, the air traffic flow management (ATFM) system has been operational since November 2019, under which 36 flow management positions over major airports in the country have been integrated with AAI’s central command centres to give the necessary recommendations to air traffic controllers. The ATFM system recommends the optimum arrival sequence along with the time to lose well in advance so that pilots can be informed early enough to absorb delays en route when demand exceeds capacity. Some of the key benefits of the centralised ATFM are enhanced flight safety, improved on-time arrivals, minimisation of air congestion, optimisation of passenger/crew/aircraft connections and minimisation of turnaround times, besides fuel savings.
AAI has also embarked on the provision of mobile air traffc control (ATC) towers, wherein about eight such systems have been procured to be used during exigency conditions. AAI has also been working on the system of remote ATC control towers to control airstrips at remote locations from the control centre, thus avoiding the need to deploy manpower at such scantily used airports like those in the Northeast. Remote tower solutions provide a smarter approach to ATC by digitalising and integrating airport functions, whether the airport is an international hub, a small regional airport, or a new airport. The authority has also introduced the automatic message handling system, an upgradation over the existing automatic message switching system. Presently, an expression of interest has been issued for the same, while the concept for a combined database is being finalised so that data can be transmitted to the users in a timely manner. An online flight plan management system is also likely to be implemented by February-March 2021 for registered users on mobile platforms as well. Besides, AAI is planning to switch to the Aeronautical Information Management system from the present Aeronautical Information Service system. The switch has been principally agreed upon and AAI is taking the necessary steps in this direction. w
Based on inputs from a presentation by Nikhil Ranjan Das, Executive Director, CNS-OM, AAI, at a recent India Infrastructure conference