What happened
On November 13, 2020, an Air India Airbus A3/20, registration VT-EXM, was prepared for a scheduled flight from Chennai to Delhi. During the taxi phase, the crew requested departure from intersection 'A' to optimize performance. While the initial taxi instructions were for runway 25, the revised clearance directed the aircraft to hold at runway 30.
As the aircraft approached the runway, the crew became confused regarding the active runway. Despite receiving clearance for runway 25, the aircraft lined up on runway 30. The crew initiated the take-off roll on this unassigned runway, but Air Traffic Control (ATC) immediately intervened, ordering the pilot to cancel the take-off and stop. The pilot rejected the take-off at a speed of approximately 67 knots.
Following the aborted take-off, the crew attempted to taxi back to the bay but inadvertently turned onto taxiway 'N', which was not a valid taxiway. The incident concluded with the aircraft being unable to respond to ground communications for a period, eventually requiring a tow back to the terminal.
The investigation
AAIB India examined the cockpit actions, ATC communications, and the aircraft's technical configuration. The investigation focused on why the crew failed to identify the incorrect runway and why the aircraft deviated from its taxi path. Investigators also reviewed the crew's briefing procedures and the airport's visual aids. The inquiry noted that the crew was operating in a high-pressure environment, influenced by the desire to complete the flight during a festive season and the presence of an arriving aircraft on final approach.
Findings
- The primary cause was a loss of situational awareness by the flight crew, specifically the pilot flying failing to verify the intended runway using visual cues and the pilot monitoring failing to properly monitor instruments.
- The crew did not observe the aircraft's heading, which was inconsistent with the intended runway 25.
- The crew failed to discuss known airport 'hotspots' during their pre-taxi briefing.
- The timing of the ATC take-off clearance, issued while the aircraft was already lining up on the wrong runway, inadvertently reinforced the crew's incorrect belief that runway 30 was the assigned path.
- The aircraft was not equipped with the TOS2 function, which could have provided an automated alert regarding runway mismatch.
Safety action
- It is recommended that operators implement specific procedures for departures from runway intersections.
- Operators should emphasize the discussion of airport hotspots during all taxi briefings.
- Aerodrome operators should consider installing additional visual aids, such as runway lead-in or stop bar lights, at intersections to prevent incursions.
- The investigation suggests that A320 operators should evaluate the installation of Take-off Surveillance and Monitoring functions to enhance safety.