Over 100 flights delayed at Delhi airport after major ATC system failure

Flight operations at Delhi’s Indira Gandhi International Airport (IGIA) descended into disarray on Friday morning after a technical glitch crippled the Air Traffic Control (ATC) system, delaying more than 100 flights and stranding hundreds of passengers. The snag, traced to a failure in the Automatic Message Switching System (AMSS), the communication network that powers the Auto Track System (ATS) for flight plan generation, disrupted normal air traffic coordination across northern India.

The disruption, which began late Thursday, forced controllers at India’s busiest airport to manually prepare flight plans, a process described as “slow and cumbersome,” leading to widespread delays and airspace congestion. “The issue lies with the AMSS that supplies information for the Auto Track System. Controllers are preparing flight plans manually, which is taking significant time,” a senior airport source said.

IGIA, which handles over 1,500 flight movements daily, saw departures and arrivals thrown off schedule through the morning. By 9 a.m., flight tracking portal Flightradar24 showed average departure delays of 45 to 50 minutes. The ripple effect extended to several northern airports, including Lucknow, Jaipur, Chandigarh, and Amritsar.

A spokesperson for Delhi International Airport Ltd (DIAL) confirmed that flight operations were affected by a technical issue in the ATC system and said, “Teams are working closely with the Airports Authority of India (AAI) to restore normalcy at the earliest.”

Meanwhile, airlines including IndiGo, SpiceJet, and Air India issued advisories alerting passengers to possible disruptions. IndiGo posted on X, “Flight operations at Delhi Airport are currently experiencing delays due to a technical issue with the Air Traffic Control system,” adding that its ground staff were assisting stranded passengers. SpiceJet stated that all departures and arrivals “might get affected” due to ATC congestion, while Air India expressed regret over “the inconvenience caused by this unforeseen disruption, which is beyond our control.”

At the terminals, passengers reported long queues, extended waits onboard aircraft, and multiple rescheduling announcements. Many took to social media to complain about being stuck for hours without information from airlines.

By noon, AAI officials said partial stability had been restored, but operations remained slower than usual. “ATC operations are stable but slower than usual. Restoration work is in progress,” a senior AAI official said, adding that clearing the backlog could take several hours.

The AMSS glitch, though temporary, underscored the heavy dependency of modern aviation systems on automated coordination tools. As engineers continued restoration efforts, the morning’s chaos served as a stark reminder of how a single point of failure can bring an entire network to a halt.