More than 150 flights leaving Delhi’s Indira Gandhi International Airport were delayed on Friday morning after a major technical glitch hit the air traffic control system.
The problem was traced to a failure in the Automatic Message Switching System, the software that sends essential flight plan information to the tracking system used by air traffic controllers.
According to the Airports Authority of India, the fault forced controllers to switch to manual processing of flight plans, which slowed down operations and led to long queues of aircraft waiting for clearance. The authority said technical teams were already working to restore the system and requested passengers to cooperate during the disruption.
Delhi Airport normally manages over 1,500 flight movements a day, making it the country’s busiest aviation hub. Data from Flightradar24 showed that more than 500 flights had already faced delays on Thursday, and another 171 were delayed by Friday morning. Many morning departures were running almost an hour behind schedule, with delays rising as the day progressed.
Officials familiar with the issue said the malfunction began around 3 pm on Thursday, and since then controllers have been forced to create and verify flight plans manually—something that significantly slows down departures. One official described the situation inside the ATC as “chaotic,” noting that such a failure had not been seen before.
Airlines began issuing alerts to passengers. IndiGo informed flyers that flights to and from Delhi, as well as some other northern airports, were being affected, and asked customers to expect longer wait times. Air India also posted an update, calling the disruption “unforeseen” and advising passengers to check their flight status before heading to the airport.
The delays are expected to continue until the system is fully restored.
