GPS spoofing disrupts Delhi airport flights: What happened and how it hit air operations — Explained

The issue has been particularly severe during easterly wind conditions, which have forced aircraft to approach from the Dwarka side and depart toward Vasant Kunj, creating congestion, delays, and multiple diversions.

What is GPS spoofing?

GPS spoofing involves transmitting fake satellite signals that deceive GPS receivers, causing them to register false location, navigation, and timing data.

Unlike GPS jamming—which simply blocks signals—spoofing actively feeds incorrect coordinates, misleading aircraft navigation systems about their real position.

While similar incidents have been reported in sensitive regions such as the Black Sea, this is the first recorded case of GPS spoofing at Delhi’s IGI Airport, marking a serious concern for civil aviation safety in India.

How does it affect flight operations?

The disruption has been aggravated by the temporary shutdown of the Instrument Landing System (ILS) on IGI’s main runway (10/28), which is undergoing upgrades to enhance visibility handling during the dense winter fog season.

With the ILS offline, aircraft have had to rely on Required Navigation Performance (RNP)—a system that depends heavily on GPS signals.

Spoofed signals, reportedly affecting navigation up to 60 nautical miles from the airport, have resulted in severe operational hurdles.

In recent days, five IndiGo and two Air India flights were forced to divert to Jaipur due to inaccurate GPS readings.

How did airlines and authorities respond?

In response, the airport’s Automatic Terminal Information Service (ATIS) has been broadcasting alerts, advising pilots to remain cautious when entering Delhi’s airspace and to use alternate navigation systems wherever possible.

Delhi International Airport Ltd (DIAL) and the Directorate General of Civil Aviation (DGCA) are expediting efforts to restore ILS functionality, aiming for completion by November 27.

IndiGo has already conducted trial flights to test the upgraded approach lighting system, with results shared with the DGCA.

An aviation official emphasised the urgency of restoring ILS operations: “The priority now is to bring ILS back on runway 10/28 as soon as possible.”

Growing threat to global aviation

Experts caution that GPS spoofing represents a growing hazard to civil aviation worldwide.

Originally developed for military purposes—to obscure the location of strategic assets—spoofing in commercial airspace poses significant risks.

False GPS data can mislead aircraft by as much as 2,500 kilometres, creating dangerous navigation discrepancies.

Airlines have started briefing pilots about known spoofing hotspots and encouraging the use of conventional radio-based navigation aids during suspected spoofing incidents.

Authorities, while acknowledging the seriousness of the situation, have avoided speculating on the origins of the spoofing attacks due to security sensitivities.

Their immediate focus remains on restoring the ILS and minimising operational vulnerabilities.

Once the upgrade is completed, IGI’s primary runway will feature Category III capabilities on both ends—enabling landings in extremely low visibility and strengthening the airport’s resilience against future technical disruptions and environmental challenges.