Air traffic controllers at Delhi’s Indira Gandhi International Airport (IGIA) had reportedly warned authorities months before the major technical glitch that disrupted hundreds of flights. In a letter sent in July 2025, the Air Traffic Controllers’ Guild of India raised concerns about the aging automation systems used for managing air traffic, citing frequent slowdowns and lag during high-traffic hours. According to the Guild, the Automatic Message Switching System (AMSS) — responsible for flight plan exchanges and data communication had shown signs of “performance degradation.” They had requested urgent upgrades and technical evaluations, highlighting that delays in modernization could affect flight safety and efficiency. Despite these warnings, no significant action was taken at the time.

The warning gained renewed attention after a large-scale disruption occurred in early November 2025, when the AMSS malfunctioned, forcing controllers to manually handle flight plans. The glitch led to the delay of over 800 flights and caused widespread chaos at Delhi Airport. Aviation experts noted that if the earlier alerts had been addressed, the failure could likely have been avoided.

The Airports Authority of India (AAI) has since promised an internal review and accelerated modernization of critical air traffic systems. Authorities also plan to enhance redundancy mechanisms and align technology upgrades with global aviation standards to prevent future disruptions.