Delhi Airport System Failure Reveals Critical Flaws in India's Air Traffic Infrastructure, Controllers Guild Warns

The disruption forced air traffic controllers to manually process over 2,500 daily aircraft movements.

New Delhi:

The Air Traffic Controllers' Guild (India) has expressed significant concerns regarding the recent Automatic Message Switching System (AMSS) failure at Delhi's Indira Gandhi International Airport, describing it as "more than a technical glitch and a reflection of deeper systemic issues in India's air traffic infrastructure."

In their correspondence to Civil Aviation Minister Ram Mohan Naidu, the Guild emphasized that this failure represents not merely an isolated technical incident but rather highlights deficiencies in the nation's aviation communication and navigation readiness.

The system disruption, occurring between November 6-8, 2025, compelled air traffic controllers to manually handle over 2,500 daily aircraft movements, including more than 1,500 scheduled flights and 1,000 overflying aircraft.

The Guild characterized the failure as "infrastructural, not operational, a clear lapse in system maintenance and timely replacement," noting that the Electronics Corporation of India Limited (ECIL)-supplied AMSS failed due to technical issues and was restored only following direct ECIL intervention. The system had already operated beyond its OEM-supported validity period, while procurement and upgradation processes faced delays.

Their letter criticized the Airports Authority of India for maintaining an expensive, personnel-heavy model for its Communication, Navigation and Surveillance (CNS) systems. It pointed out that while global equipment manufacturers like Thales, Indra, Raytheon, ECIL, Honeywell and BEL provide worldwide lifecycle support with smaller teams, AAI employs approximately 500-600 CNS personnel merely to manage about 50 MSSR radar systems. In contrast, OEM ELDIS Pardubice operates hundreds of radar systems globally with only around 250 staff.

The Guild argued that this domestic approach effectively doubles AAI's costs without enhancing efficiency, and advocated for OEM-backed maintenance and support contracts to ensure accountability and reliability.

They also cautioned that such outdated infrastructure and procurement delays could have broader safety implications. "ATC is the only real-time safety-critical service in AAI governed by ICAO and DGCA regulations, where even minor errors have direct safety consequences," the Guild observed.

The letter referenced previous submissions to the Parliamentary Standing Committee on Transport, Tourism and Culture, which had already highlighted performance deterioration in automation systems at high-density airports. The Committee's 380th report, presented in August 2025, recommended urgent review and modernization of air traffic automation.

To avert future system failures, the Guild proposed several structural reforms, including a government-led investigation into the AMSS failure, accountability for responsible officials, and reviewing automation upgrades at other major airports such as Mumbai and Bengaluru. They also urged implementing redundancy systems like parallel AMSS servers and modern automation tools to ensure operational continuity.

The Guild noted that despite the AMSS malfunction, air traffic controllers ensured safe operations under extreme pressure by manually generating flight plans and coordinating closely with Air Defence and ECIL engineers for system restoration.