Flight operations at Delhi’s Indira Gandhi International Airport (IGI) were severely disrupted on Friday morning after a significant technical malfunction in the air traffic control system caused delays to more than 150 flights. As India’s busiest airport, handling over 1,500 aircraft movements every day, IGI experienced widespread operational slowdowns that affected both domestic and international passengers. The disruption originated from a failure in the Automatic Message Switching System (AMSS), a critical component that transmits flight plan information to the Auto Track System used by air traffic controllers. With the AMSS offline, air traffic personnel were forced to process flight plans manually, resulting in extended delays throughout the morning.

The Delhi airport authorities issued a statement acknowledging the disruptions and advised passengers to stay in close contact with their respective airlines for the latest updates. The airport emphasised that the technical issue lay within the ATC infrastructure and not with airport operations themselves. Officials said efforts were underway to restore the system as quickly as possible, and they expressed regret for the widespread inconvenience caused to passengers who were left waiting inside terminals and onboard aircraft that were unable to depart on schedule.

Major airlines operating at Delhi, including Air India, IndiGo and SpiceJet, issued their own advisories to passengers in an attempt to manage expectations and provide updated information regarding flight statuses. The airlines also deployed additional ground staff to assist passengers experiencing prolonged wait times.

Air India noted in its statement that a “technical issue with the ATC system in Delhi is impacting flight operations across all airlines,” resulting in delays and extended wait times both inside the terminal and onboard aircraft already prepared for departure. The airline urged passengers to verify their flight status before travelling to the airport, stressing that the situation was beyond its control. It added that cabin crew members and on-ground operational staff were doing everything possible to help affected passengers and to reduce discomfort caused by the delays.

IndiGo, the country’s largest airline by market share, echoed similar concerns. In its advisory, it stated that “flight operations at Delhi Airport are currently experiencing delays due to a technical issue with the Air Traffic Control system.” The airline explained that the disruption not only affected Delhi but also had a cascading impact on several northern sectors that rely on Delhi’s ATC network for traffic flow management. IndiGo directed passengers to visit its website for the most accurate and timely information on flights, adding that its teams were working diligently to assist customers both inside the airport and on grounded aircraft. The airline acknowledged that extended wait times could cause inconvenience but assured passengers that efforts were underway to stabilise operations as soon as the ATC system was restored.

SpiceJet also released an advisory cautioning passengers to check their flight status before heading to the airport. The airline confirmed that the disruption had affected multiple northern regions and that flight departures from Delhi were experiencing significant delays. SpiceJet expressed regret for the inconvenience and stated that its ground and flight crews were providing necessary support to passengers stranded at the airport. It added that the airline was coordinating with airport authorities and ATC personnel in an effort to expedite the resumption of normal operations as soon as technical issues were resolved.

Within the airport, the impact was visible across terminals. Passengers reported long queues at check-in counters, security lanes, and boarding gates. Several flights experienced delays exceeding an hour, while others were held in a standby mode awaiting clearance from air traffic control. Flight-tracking services showed a marked increase in delayed departures compared to usual schedules, reflecting the bottleneck caused by the ATC malfunction. Some passengers took to social media to express frustration over the lack of timely updates, while others acknowledged that the situation was beyond the airlines’ control and urged fellow travellers to remain patient.

Officials familiar with the matter explained that the issue began on Thursday afternoon, when the AMSS system first showed signs of malfunction. Although technicians attempted to resolve the problem overnight, the system had not been fully restored by Friday morning, resulting in a backlog of flights. When the AMSS fails, air traffic controllers must manually input and process flight plans—a process that is significantly slower and more prone to delays. As a result, the number of flights that can be cleared for departure per hour is reduced, causing widespread schedule disruptions.

The malfunction also affected flight sequencing and gate assignments, further complicating efforts to maintain smooth operations. With Delhi serving as a key hub for many carriers, delays quickly spread beyond the airport, affecting connecting flights and operations in other northern cities. Aviation analysts noted that such instances, though rare, underline the heavy dependence of modern airports on automated systems and the challenges that arise when even one component fails.

Airport authorities confirmed that technical teams were working intensively to restore the AMSS and resume automated flight data management. They emphasised that passenger safety remained the highest priority and that no compromises would be made in air traffic handling procedures. The airport stated that it would provide further updates as the restoration efforts progressed and thanked passengers for their patience.

Airlines also emphasised that they were ready to adjust schedules and accommodate re-bookings once ATC operations regained stability. Some carriers said they were exploring options to redeploy additional aircraft or modify flight rotations to minimise cascading delays later in the day. Passengers were encouraged to arrive at the airport only after confirming the latest status of their flights through airline websites or customer service helplines.

The situation highlighted the importance of resilient air traffic management infrastructure in India’s rapidly expanding aviation sector. As passenger volumes continue to grow and India’s airports handle increasing numbers of aircraft movements, ensuring redundancy and reliability in essential systems such as AMSS becomes critical. Aviation experts noted that while manual processing offers a temporary fallback, it is not sustainable for long durations in a high-traffic environment like Delhi.

By late morning, efforts to stabilise operations were ongoing, but the full restoration of services was expected to take additional time. Passengers were advised to stay alert for notifications from airlines and to prepare for potential extended delays throughout the day.

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