Operations Operations at Delhi’s Indira Gandhi International Airport (IGIA) were severely disrupted on November 6 after a key Air Traffic Control (ATC) system called the Automatic Message Switching System (AMSS) suddenly failed. As a result, more than 800 flights were delayed, and several others had to be rescheduled. While flight safety was never compromised, the communication slowdown created a massive operational backlog that lasted for several hours.
What was the issue?
The breakdown in communication between airlines, pilots, and controllers brought operations to a near halt, causing widespread flight delays across the country. Because Delhi is India’s busiest aviation hub, the impact was felt nationwide.
The problem began when the AMSS—a vital software used by ATC—stopped functioning. Normally, this system automatically exchanges crucial flight plan data such as routes, schedules, and aircraft details, between pilots, airlines, and air traffic controllers. When it failed, controllers were unable to send or receive flight data electronically.
To keep flights moving, ATC teams had to manually input and verify every piece of flight information, including clearances and separation details for takeoffs and landings. This manual process is much slower than automated systems, leading to long queues both on the ground and in the air.
Officials from the Airports Authority of India (AAI) confirmed that the issue was eventually resolved and the system restored. The AAI is now working to add backup systems and strengthen redundancy to prevent similar failures in the future. A detailed technical review is also underway to determine the exact cause of the glitch.
Other concerns
Around the same time, there were reports of possible GPS spoofing incidents near Delhi. GPS spoofing refers to the transmission of false satellite signals that can mislead aircraft about their actual location. Although no direct link between the spoofing and the ATC failure has been confirmed, authorities are investigating whether these issues may have worsened the disruption.
What the government said
The Civil Aviation Ministry has ordered a comprehensive root-cause analysis of the failure. Meanwhile, the Air Traffic Controllers’ Guild has called for a full probe, raising concerns about aging infrastructure and the urgent need for faster system modernisation.
In short, the Delhi Airport glitch was primarily caused by the failure of a crucial communication system, possibly compounded by navigation signal issues — highlighting the urgent need for stronger backups and modernised air traffic technology.