On Monday night at 8:40 PM, Air India’s Mumbai-bound flight AI 2957 sent an emergency signal to Delhi’s Air Traffic Control (ATC), indicating a possible hijack just after takeoff from Indira Gandhi International Airport. The distress signal immediately activated high-level security protocols, alerting the destination airport, security agencies, and the Indian Air Force.
Swift Response Despite False Alarm
Despite the pilot later clarifying that it was a false alarm, authorities did not assume it was an error. A former ATC official, speaking anonymously, explained the cautious approach:
“ATC cannot assume that the pilot is not under duress. He could be at gunpoint, forced to declare everything is normal.”
The flight, carrying 126 passengers, landed in Mumbai at 9:47 PM, where authorities had already declared a full emergency at 9:30 PM. An aerodrome committee was formed at Mumbai airport, and personnel from the local police, National Security Guard (NSG), and other stakeholders were deployed.
The aircraft was moved to an isolation bay, and passengers were only allowed to deboard after an hour once security checks confirmed there was no threat.
What Triggered the Alarm?
According to Delhi airport officials, the situation arose when the aircraft’s transponder sent a ‘Squawk 7500’ code to Delhi ATC just after takeoff. The signal remained active for three minutes before being turned off.
Understanding Squawk Codes:
🔹 7500 – Unlawful interference (hijack) 🚨
🔹 7600 – Radio communication failure 📡
🔹 7700 – Aircraft emergency ⚠️
Since 7500 is specifically used for hijack situations, authorities treated it as a real threat until thorough verification was completed.
Lessons from the Incident
While this was a false alarm, it demonstrated the effectiveness of India’s aviation security protocols. The rapid mobilization of ATC, airport authorities, CISF, BCAS, IAF, and NSG ensured that all necessary precautions were taken.
The incident highlights the importance of strict protocol adherence in aviation security, as any deviation could have catastrophic consequences. Authorities are now investigating the exact reason behind the false transponder signal.
