AVIATION/ AIR INDIA & CHINA EASTERN JETS IN NEAR COLLISION

Aviation officials in India and Bangladesh have opened an investigation into an incident on Thursday that had 2 airliners on a collision course. A disaster was averted when one of the Pilots made a rapid descent following an inflight TCAS alert. According to media reports, aviation officials at the Kolkata Airport in India, suspect an oversight by the officials at the Dhaka Airport in Bangladesh, in whose airspace the flights came too close to each other, is to blame for the near collision. The 2 airliners involved were an AIR INDIA A319 enroute from Kolkata to Imphal and a CHINA EASTERN AIRLINES aircraft enroute from Kathmandu to Shanghai. Sources at the Kolkata ATC said the Air India plane had taken off around 12:00pm and flew 30 nautical miles before entering the zone region of Dhaka Airport. Kolkata ATC had approved the Air India plane to fly at 310000 feet, which the aircraft was flying. However, when he contacted Dhaka ATC, the Pilot told him he had been approved to 33000 feet. Dhaka ATC then told the Air India Pilot to ascend to 33000 feet. According to the Kolkata Airport, they knew, as did Dhaka, that the China Eastern plane was already at 33000 feet. The China Eastern plane from Kathmandu was approaching the Air India flight path at an angle of 45 degree from the left. “When the 2 came close to each other near Comilla in Bangladesh around 12:30pm, the Traffic Collision Avoidance System TCAS issued an alert that they were on a collision course. The Air India Pilot immediately descended 2000 feet,” the official from Kolkata said. It is not clear how close the 2 airliners came to each other. Officials in Kolkata and Dhaka are are conducting parallel inquiries. Most northeast-bound aircraft from Kolkata fly 30 nautical miles before entering Dhaka’s airspace zone at Nokat. After flying for about 100nm within Dhaka's zone, aircraft  reenter India’s airspace near Agartala. There is no voice communication between Dhaka and Calcutta ATCs. The Pilots communicate instructions of one ATC to another through a very high frequency mode of communication An official said there is a hotline between the Kolkata and Dhaka, but it’s "rarely" used.