IndiGo plane turned left after take-off from Delhi, triggered collision alert: AAIB

On Nov 17, the Delhi-Hyderabad flight received departure clearance from the northern runway system which includes runway 27 at 12 noon and departed at 12.31 pm

NEW DELHI: An IndiGo aircraft operating on the Delhi-Hyderabad route turned left after take-off and came dangerously close to another IndiGo flight that took off for Raipur from the Delhi airport in November last year, according to a preliminary report released by the Aircraft Accident Investigation Bureau (AAIB).

An IndiGo Airlines Airbus A320 aircraft (REUTERS FILE PHOTO)

The report, uploaded to the AAIB website, said the proximity between the two aircraft set off the Traffic Alert and Collision Avoidance System, or TCAS, which monitors airspace around a plane for other aircraft equipped with corresponding transponders and gives pilots warning of collision risks.

“At the time of the closest vertical separation (400 feet), lateral separation was 1.2 NM. At the time of the closest lateral separation (0.2 NM), vertical separation was 800 feet,” the report said. There was no injury to any of the occupants on board both aircraft or any damage to the aircraft.

IndiGo has not commented on AAIB’s preliminary findings.

According to the initial probe report, one of IndiGo’s A321 aircraft was scheduled to operate flight 6E 2113 from Delhi to Hyderabad while the second aircraft, an A320, was scheduled to operate 6E 2206 from Delhi to Raipur.

“At the same time, 6E 2206 (to Raipur) received clearance and departed from RWY 29R climbing to 4000 feet…. And the controller instructed it to climb to 4000 feet,” the report said.

“During this sequence, a breach of separation occurred between 6E 2113 and 6E 2206, triggering a Current Conflict alert..” the report said.