According to reports, more than 400 flights were delayed on Friday alone, as controllers struggled to manage operations amid both spoofing interference and a separate technical glitch in the Air Traffic Control (ATC) system. The cascading impact spread across North India, disrupting schedules at several major airports.
Earlier in the week, Delhi Airport ranked second globally for flight delays, as reported by the Times of India.
At least seven flights had to be diverted to nearby airports such as Jaipur and Lucknow, even though all four of Delhi’s runways were fully operational. On Tuesday, the Navigation Integrity Category value—a critical measure of aircraft positioning accuracy—fell dramatically from 8 to 0, raising alarms within the aviation community. Pilots reported these irregularities within a 60-nautical-mile radius of Delhi, prompting the Directorate General of Civil Aviation (DGCA) to initiate an investigation, as confirmed by The Hindu.
The situation was worsened by the temporary shutdown of the main runway’s Instrument Landing System (ILS), which provides ground-based precision guidance to pilots during landings. The ILS is currently being upgraded to Category III, which will allow landings even in dense fog—a major requirement ahead of Delhi’s winter season. However, its unavailability has forced aircraft to rely heavily on satellite-based navigation systems, making them more vulnerable to spoofing attacks.
GPS spoofing, a complex form of cyber interference, involves the deliberate transmission of counterfeit satellite signals to trick navigation systems.
Unlike GPS jamming, which blocks genuine signals, spoofing feeds in false ones, making aircraft believe they are in a different location. For example, a jet actually flying over Delhi could appear to be over Chandigarh on cockpit instruments, potentially leading to dangerous course deviations. Such cyber manipulations have grown more frequent worldwide, raising serious safety concerns for both commercial and military aviation.
In India, GPS spoofing incidents are not entirely new. The Centre informed Parliament earlier this year that 465 such cases were recorded between November 2023 and February 2025 along the India-Pakistan border, primarily near Amritsar and Jammu. A report by the International Air Transport Association (IATA) also revealed that over 430,000 cases of GPS jamming and spoofing were documented globally in 2024, a 62% increase from the previous year.
The consequences of such interference have sometimes been deadly.
In December 2024, an Azerbaijan Airlines aircraft crashed in Kazakhstan, reportedly due to Russian anti-aircraft systems misidentifying it amid GPS signal disruption. Earlier this year, an Indian Air Force aircraft flying humanitarian aid to earthquake-hit Myanmar encountered GPS spoofing suspected to originate from Chinese-enabled systems. Data from the GPSjam portal shows India’s borders with Pakistan and Myanmar among the world’s top five regions with poor navigation accuracy for aircraft.
With Delhi Airport handling over 1,550 flights daily, even brief interruptions can cause widespread delays and logistical chaos. The Airports Authority of India (AAI) has assured that technical teams are working to strengthen the ATC system and implement safeguards to prevent future interference. As investigations continue, the recent incidents serve as a crucial reminder of the evolving cybersecurity challenges in modern aviation and the urgent need for resilient navigation infrastructure to ensure passenger safety in increasingly contested airspace.
