Airline operations at Delhi’s Indira Gandhi International Airport began to stabilise on Saturday morning, a day after a technical malfunction in the air traffic control system disrupted more than 800 flights at India’s busiest airport.
The glitch affected the Automatic Message Switching System (AMSS), a key component of the air traffic control’s flight planning network, and persisted for over 15 hours — from around 5:45 a.m. on Friday until the Airports Authority of India (AAI) announced the issue had been resolved at about 9 p.m.
The airport, which has four runways and manages more than 1,500 flight movements daily, saw widespread delays and several cancellations, stranding hundreds of passengers across terminals.
By Saturday morning, Delhi International Airport Ltd (DIAL), the airport operator, said systems were gradually returning to normal.
“Airline operations at Delhi Airport are returning to normal, and all concerned authorities are working diligently to minimise any inconvenience caused,” DIAL said in a post on X.
IndiGo, India’s largest carrier, also confirmed ongoing efforts to stabilise flight operations. “The airport operator and Air Traffic Control (ATC) teams are working on priority to fully restore systems and stabilise operations,” the airline said on X. “The situation is expected to be normalised over the next few hours. During this period, some departure and arrival timings may continue to be adjusted.”
Information available on flight tracking website Flightradar24.com showed that over 200 flights were delayed at the airport, including arrivals and departures, on Saturday morning.
It could not be immediately ascertained whether the flight delays were only due to the AMSS issue which is gradually improving.
While the AMSS started facing the technical issue Thursday late afternoon, the outage with the system happened at around 5:45 am on Friday, following which air traffic controllers had to prepare flight plans manually, according to sources.
The AAI, which provides navigation and other services, had also deployed additional manpower to prepare the flight plans manually which is a time-consuming process.
On Friday evening, the AAI said it has addressed the "technical issue in the AMSS, which caused delays in processing flight plan messages".
The issue was detected in the IP-based AMSS system on November 6.
"The OEM (Original Equipment Manufacturer) was engaged, and additional staff were deployed to manually process Flight Plans for the Air Traffic Control system to ensure uninterrupted and safe air traffic operations immediately.
"A team of ECIL officials and AAI personnel is still on site. The AMSS systems are up and functional now. Due to some backlogs, there may be some delays in the normal functioning of automated operations, but the situation will be normal soon," the AAI had said.
