IndiGo Aircraft Narrowly Avoid Collision After Takeoff in Delhi

In a hair-raising event that underscores the critical importance of air traffic control and adherence to flight paths, two IndiGo aircraft—an Airbus A320neo and an A321neo—came perilously close to each other shortly after taking off from Delhi's Indira Gandhi International Airport in November 2023. The incident, now under investigation by India's Aircraft Accident Investigation Bureau (AAIB), has raised concerns about air safety protocols and the need for stringent adherence to assigned routes.

A Close Call

The incident unfolded on November 17, 2023, when the two aircraft, destined for Hyderabad and Raipur, respectively, breached the minimum separation distance required for safe flight operations. According to the AAIB's preliminary report, the closest point of approach saw the aircraft at a mere 400 feet vertical and 1.2 nautical miles lateral separation—a stark deviation from the International Civil Aviation Organization (ICAO) standards that mandate a minimum vertical separation of 1,000 feet below 29,000 feet.

Route Deviation and Immediate Danger

The near miss occurred when the Hyderabad-bound A321neo, after taking off from runway 27, deviated from its assigned path and veered towards the Raipur-bound A320neo, which had just taken off from runway 29R. This deviation triggered the Traffic Alert and Collision Avoidance Systems (TCAS) on both aircraft, alerting the pilots to the imminent risk of collision and enabling them to take evasive action.

Not an Isolated Incident

This incident is not an isolated occurrence for IndiGo, India's largest airline by market share. A similar situation was reported in 2022 in Bengaluru, involving two of the airline's flights that came dangerously close to colliding due to an air traffic control oversight during a shift change. Such incidents highlight the crucial role of air traffic controllers in ensuring the safety of flights and the potential consequences of lapses in communication or adherence to flight protocols.

Investigation and Implications

The AAIB's ongoing investigation into the November incident aims to uncover the specifics of the near miss and implement measures to prevent similar occurrences in the future. As the aviation industry continues to recover and grow in the post-pandemic era, the focus on safety and adherence to protocols remains paramount to safeguarding passengers and ensuring the trust in air travel.

The incident serves as a stark reminder of the fine margins within which air safety operates and the continuous need for vigilance, both from air traffic control and flight crews, to maintain the high standards of safety that have come to be expected in modern aviation.