At Delhi’s Indira Gandhi International Airport more than 300 flights were delayed on Friday due to a technical issue affecting the Air Traffic Control (ATC) system, according to Flightradar24 data. The Airports Authority of India (AAI) said teams are working to restore the Automatic Message Switching System (AMSS), which supports ATC data exchange. Passengers were advised to check flight updates before traveling, and airlines said staff were deployed to assist. The airport’s website showed departure delays of up to nearly an hour, with waiting times increasing as congestion grew across terminals.
With the system malfunction continuing, air traffic controllers are preparing flight plans manually, a slower and more time-consuming process that has resulted in widespread delays and airspace congestion. Airport Authority of India posted on X, "Flight operations at Delhi Airport are experiencing delays due to a technical issue in the Automatic Message Switching System (AMSS), which supports Air Traffic Control data. Controllers are processing flight plans manually, leading to some delays. Technical teams are working to restore the system at the earliest. We appreciate the understanding and cooperation of all passengers and stakeholders." Long queues were reported inside terminals, and many passengers were waiting near gates for updates.
Delhi Airport posted on X, " Flight operations at Delhi Airport has been disrupted due to an ongoing technical issue with the Automatic Message Switching System (AMSS) that supports Air Traffic Control flight planning process. All airline operations at Delhi Airport arecurrently delayed. Concerned authorities are working on resolving the issue at the earliest. Passengers are requested to follow updatesfrom their airlines regarding revised schedules. Thank you for your cooperation."
Airlines also issued advisories requesting travelers to verify flight schedules and arrive early. IndiGo posted on X, "#6ETravelAdvisory The AMSS system issue impacting ATC operations is still being resolved, and delays may continue across airlines at #Delhi and a few airports in the northern region until the system is fully restored. Customers with upcoming departures are advised to check the latest flight status before starting their journey http://bit.ly/2EjJGGT and to arrive at the airport a little earlier than usual to allow additional time for travel formalities. Our teams are available across counters and boarding gates to assist with any support required. Thank you for your understanding and patience.”
Air India wrote, “#TravelAdvisory A technical issue with the ATC system in Delhi is impacting flight operations across all airlines, leading to delays and longer wait times…” Authorities, including ATC and DIAL, are continuing to work on restoring normal operations. As Delhi is India’s busiest airport, disruptions here have a cascading effect on domestic and international schedules.
What Is ATC System?
Air traffic control (ATC) is a ground-based service where trained controllers oversee and guide aircraft movement both at the airport and in the surrounding airspace. As per the airport’s website, departures on Friday morning were running late by as much as 53 minutes, and waiting times continued to rise. A technical malfunction in the ATC messaging system at Delhi airport has caused widespread delays. Since the system is down, controllers are now manually preparing flight plans using available information, which is a slower process and is contributing to increasing congestion. Authorities are currently working to resolve the issue and restore normal operations.