In the aviation ecosystem, the most critical component remains largely invisible to passengers. While terminals, lounges and retail spaces dominate public perception and political narratives, the true state of Indian aviation is demonstrated through its airside infrastructure. Every smooth takeoff, safe landing and on-time departure ultimately depends on the strength, design and efficiency of the surfaces on which aircraft operate. Therefore, attention needs to be shifted towards the airside, where capacity pressures, climate realities and technological upgrades intersect.
Aircraft movement takes place within a complex operational environment comprising runways, taxiways, aprons, airfield lighting systems, instrument landing systems (ILSs), ground vehicle coordination and air traffic sequencing. This airside network serves as the backbone of airport operations, yet it is under severe strain. Unlike terminals, which can often be expanded or aesthetically upgraded, airside infrastructure is constrained by land availability, safety regulations, environmental clearances and legacy design decisions made decades ago.
Legacy infrastructure meets modern demand
India’s airport network was largely designed for modest traffic volumes. For decades, many major airports operated with a single runway supported by limited taxiway networks. This arrangement was adequate when flight frequencies were low and airline operations were relatively predictable. However, the model began to break down rapidly following the liberalisation of the aviation sector, the entry of low-cost carriers and the sharp rise in air travel in recent years. As passenger demand surged, runways were forced to operate at or beyond their intended capacity, leading to delays, increased runway occupancy times, longer taxi queues and disruptions across airline networks.
While capacity challenges are often viewed as a terminal congestion problem, they are, in reality, equally an airside constraint issue. High runway occupancy times reduce the number of movements that can be safely handled per hour, creating bottlenecks that terminal expansion cannot resolve.
Recognising these constraints, airports across the country have started investing in airside modernisation. Airports are not only building new runways but also optimising existing ones through better taxiway geometry, rapid exit taxiways, improved apron layouts and advanced navigation systems. Kempegowda International Airport at Bengaluru, Karnataka, has upgraded its north runway (09L/27R) to Code F compliance, enabling it to handle large aircraft, including the Airbus A380 and Boeing 747-8.
Delhi provides a contrasting example of how airside planning can transform operational efficiency. With multiple runways, optimised exit taxiways, and segregated arrival and departure flows, the airport has been able to scale capacity while maintaining resilience during adverse weather conditions. In contrast, Mumbai demonstrates how legacy runway geometry can restrict growth even at one of the country’s most commercially successful airports. The two intersecting runways cannot be used simultaneously for independent operations, and maintenance at the intersection makes both runways inoperable. These differences show that an airport’s capacity depends more on airside efficiency than terminal size.
Several airports have recently made significant improvements. At Ahmedabad’s Sardar Vallabhbhai Patel International Airport, new Code C parallel taxiways, Taxiway R and Taxiway R1, were commissioned in November 2025. These upgrades expanded runway handling capacity by 40 per cent, increasing air traffic movements from 20 per hour to 28 per hour while enabling 95 per cent of aircraft to avoid backtracking. Similarly, Chhatrapati Shivaji Maharaj International Airport in Mumbai commissioned Taxiway M on December 30, 2025, marking a significant upgrade to its airside infrastructure. The new taxiway strengthens the parallel taxiway network, improves departure sequencing, increases peak-hour departure capacity and provides greater flexibility for air traffic controllers. It also reduces aircraft taxi distances, lowering fuel consumption and associated carbon emissions.
Climate and geography as design drivers
The Indian context introduces an added layer of complexity as runways are required to function across an extraordinary range of climatic and geographic conditions. Airports in Leh and Shimla operate at high altitudes with thin air and extreme temperature variations, while the saline coastal environments in Mumbai and Chennai accelerate pavement deterioration. Airports in Rajasthan face desert heat and dust, while those in Kolkata and Guwahati must withstand intense monsoon rainfall and periodic flooding. These variations directly influence runway material selection, pavement thickness, drainage design and maintenance planning. Hence, several Indian airports have undertaken targeted runway recarpeting programmes to enhance pavement performance and operational reliability. At Nagpur airport in Maharashtra, runway recarpeting has been completed, and the airport has been open for 24-hour operations since April 2025. Thiruvananthapuram International Airport completed the recarpeting of its 3.4 km runway in April 2025 after 75 days of work that began in January 2025.
The Indian monsoon is the most underestimated factor in runway design. Unlike temperate regions, where rainfall is spread evenly throughout the year, India experiences concentrated rainfall over short periods. Poorly designed drainage systems can lead to water pooling on runway surfaces, forcing operational suspensions during peak travel seasons. In such cases, weak airside infrastructure becomes not just an engineering issue but a commercial and reputational one for airports and airlines alike. In view of this, airports are investing in stormwater drainage upgrades. For instance, Trichy International Airport approved a Rs 110 million project in December 2025 to strengthen stormwater drainage around its runways and aprons to prevent stagnation during rains.
In addition, advanced systems such as ILS help maintain safe operations during heavy rainfall by guiding aircraft precisely on to the runway even in low-visibility conditions. Recently, Delhi airport completed a major airside upgrade in collaboration with the Airports Authority of India (AAI), equipping the Dwarka end of Runway 10/28 with a Category III ILS. With this upgrade, all three runways – 10/28, 11L/29R and 11R/29L – are CAT III compliant at both ends, enabling approximately 30 landings per hour during dense fog, while cutting fog-related recovery time from six hours to about two.
Kolkata’s Netaji Subhas Chandra Bose International Airport achieved a major milestone on November 27, 2025, by operationalising Category III B ILS at both ends of its primary runway (19L), enabling aircraft landings in visibility as low as 50 metres from both the New Town and Madhyamgram ends, significantly enhancing operational flexibility during dense fog. In November 2025, Jaipur International Airport strengthened its airside capabilities with the commissioning of an advanced approach lighting system, upgraded runway lighting and CAT III ILS, supported by new runway markings and lighting maintenance.
Regional airports and the runway paradox
The expansion of regional connectivity under the Ude Desh ka Aam Nagrik (UDAN) scheme has connected parts of the country previously underserved by air travel, including revived airports such as Darbhanga, Jharsuguda and Tezu. Several regional airports have been developed with new terminal buildings. However, many of these airports face a structural paradox – their terminals are ready for growth, but their airside infrastructure limits the type and frequency of aircraft that can operate.
Regional airports often lack adequate navigational aids, sufficient runway length, air traffic control systems and other critical infrastructure, which constrains flight operations. At present, 14 airports developed under the UDAN scheme are non-operational, including those at Shimla, Pathankot, Ludhiana, Pakyong and Kushinagar. These disruptions are attributed to factors such as runway maintenance closures, limited operational windows and restrictions at airports that operate only under Visual Flight Rules, which prevent night or all-weather operations.
Addressing these limitations requires targeted upgrades. For example, at Keshod airport in Gujarat, the runway is being extended to approximately 2,500 metres and the terminal is being expanded to accommodate larger aircraft such as the Airbus A320, with completion expected around January 2027. Such investments in airside infrastructure are critical if regional connectivity is to translate into sustainable, commercially viable airline operations.
Technology and the intelligent airside
In recent years, Indian airports have begun embracing technology to address airside limitations. The focus has shifted towards data-driven decision-making, predictive operations and improved coordination between airport operators, air traffic control and meteorological agencies.
In December 2025, Delhi International Airport Limited (DIAL) deployed advanced artificial intelligence (AI) systems and predictive analytics through its Airport Predictive Operations Centre. By integrating real-time operational data with weather models and airside inputs, the system optimises runway utilisation, aircraft sequencing and gate allocation, particularly during winter fog events that historically disrupted operations.
To enhance predictive capabilities further, as a pilot initiative, Delhi airport is leveraging data from the winter fog experiment, a collaborative research programme launched by the Pune-based Indian Institute of Tropical Meteorology in partnership with the India Meteorological Department, AAI and DIAL, which uses advanced instruments such as light detection and ranging systems, ceilometers, aerosol counters and remote sensing towers to deliver up to 85 per cent fog prediction accuracy and forecasts ranging from 1 to 36 hours in advance.
Runway to the future
As global airside infrastructure moves towards intelligent, sensor-driven management, India’s transition has also begun but remains uneven. Technologies such as surface movement radars, advanced foreign object debris detection, digital pavement health monitoring and AI-based maintenance planning help improve operational efficiency. Even small reductions in runway occupancy time can unlock thousands of additional aircraft movements each year. However, technology adoption must be grounded in local operational realities.
Looking ahead, with passenger traffic projected to exceed 1 billion annually by the 2040s, India’s aviation growth will depend far less on terminal architecture and more on how intelligently airside systems are designed, managed and modernised. Runways are no longer passive strips of concrete. They are strategic assets shaped by climate, geography, policy and technology.