Kolkata: Two flights, one that took off from Kolkata and another that was heading to the city, came dangerously close to each other near the India-Bangladesh border on May 2. The Aircraft Accident Investigation Bureau under the civil aviation ministry is probing the incident of “airprox”.
The Agartala-bound IndiGo flight 6E 892, which took off from Kolkata, was beginning its descent after 40 minutes in the air when the traffic collision avoidance system (that warns pilots when another aircraft is too close to it) went off in the cockpit.
The plane at the other end was a non-scheduled Air Deccan flight. The plane, an 18-seater Beechcraft 1900 D that is much smaller than IndiGo’s 180-seater Airbus A-320 plane, had taken off from Agartala and was still climbing when the warning was signalled.
Officials said the flights were barely 15-35 seconds away from each other, which triggered a resolution advisory (an in-built feature in the TCAS through which an automated voice instructs each pilot of conflicting aircraft to climb or descend to ensure that they increase the vertical separation between them). The minimum vertical distance between two flights operating in Indian airspace is 1,000 feet. The two flights had come within 700 feet of each other, breaching the minimum separation clause.
“IndiGo flight 6E-892 operated by VT-IDQ aircraft was involved in an RA (resolution advisory) incident with a non-scheduled operator on May 2 while descending for landing at Agartala. The IndiGo aircraft was at the prescribed air level. The IndiGo pilot followed the standard operating procedures (SOPs) and reported the matter to Agartala ATC and the company. The matter has been reported to the regulator and is being investigated,” an airline spokesperson said.
An Air Deccan safety official also acknowledged the incident and said it was being investigated. Officials at Kolkata air traffic control (ATC) said they were unaware of the incident though Agartala ATC is under Kolkata flight information region.
12/05/18 Subhro Niyogi/Times of India