New Delhi, India: India’s Aircraft Accident Investigation Bureau (AAIB) has recommended a comprehensive one-time inspection of airlines’ safety management systems (SMS) by the Directorate General of Civil Aviation (DGCA), following its 35-page final investigation report into a serious air proximity incident involving two IndiGo aircraft in Delhi airspace on November 17, 2023.
The incident involved IndiGo Flight IGO2113, an Airbus A321 operating from Delhi to Hyderabad, and IndiGo Flight IGO2206, an Airbus A320 operating from Delhi to Raipur. The two aircraft came dangerously close to each other shortly after departure, breaching the minimum separation standards mandated for controlled airspace. Fortunately, the Traffic Collision Avoidance System (TCAS) alerts helped pilots maintain safe separation, and no injuries or damage to the aircraft were reported.
The AAIB’s final report identified multiple factors that contributed to the near-miss. The crew of IGO2113 failed to correctly set up and verify the Standard Instrument Departure (SID) data, which is critical for maintaining a safe climb trajectory. In addition, monitoring during the climb phase was insufficient, leading to reduced vertical and lateral separation from IGO2206. The bureau also noted that six previous SID deviation events involving IndiGo aircraft between August and November 2023 had not been reported through mandatory safety reporting channels, highlighting weaknesses in both the airline’s internal safety culture and compliance with regulatory requirements.
In response to these findings, the AAIB has recommended that the DGCA carry out a one-time inspection of the safety management systems of all scheduled operators and the Air Navigation Service Provider. The goal is to evaluate the effectiveness of hazard identification, risk assessment, and reporting culture, as well as compliance with mandatory occurrence reporting.
The AAIB has also emphasized that airlines must ensure that all previous and future incidents are reported promptly and accurately to both the DGCA and the AAIB. The Airports Authority of India (AAI) has been advised to review ATC procedures, particularly during high-intensity simultaneous departures, and to assess the Short Term Conflict Alert (STCA) system and airspace design to prevent future separation breaches.
IndiGo has been recommended to take corrective action by ensuring accurate entries into the Flight Management and Guidance System (FMGS), minimizing cockpit disturbances during pre-flight setup, and strengthening cross-checks during training.
Aviation safety experts note that these recommendations are critical for maintaining operational safety, especially as India’s air traffic continues to grow rapidly. The AAIB’s recommendations focus on the importance of robust safety management system audits, procedural discipline, and a culture of compliance to prevent near-misses from escalating into accidents.
The DGCA is expected to follow up on the AAIB’s recommendations, potentially conducting targeted inspections across airlines and air navigation services to identify and rectify systemic vulnerabilities. The incident and the bureau’s final report highlight the vital role of near-miss investigations in reinforcing aviation safety, ensuring that lessons from minor incidents are institutionalized and preventive measures are implemented effectively.
