Mid-air collision between two IndiGo flights averted after taking off from Bengaluru: Reports

The "breach of separation" was not reported by the Airports Authority of India (AAI), NDTV quoting sources reported.

As per the Directorate General of Civil Aviation (DGCA) the "Breach of separation" happens when two aircraft cross the minimum mandatory vertical or horizontal distance in the airspace.

Two IndiGo flights - 6E 455 going from Bengaluru to Kolkata, and 6E 246 on its way from Bengaluru to Bhubaneswar - were involved in the scare, said reports.

Both were variants of the Airbus A320.

Bengaluru airport operates two runways - north and south. On Jan 7 morning, flights were taking off from the north runway and landing on the south runway, the DGCA's preliminary report said.

A shift in charge of runway operations decided to use a single runway, the north one, for both landings and take-offs, the report said. The south runway was then closed. However, it was not informed to the south tower controller.

The south tower controller allowed the flight going to Kolkata to take off. At the same time, the north tower controller also gave permission to the flight going to Bhubaneshwar to take off to go.

The clearances by both tower controllers were given simultaneously without coordination, the DGCA's preliminary report said.

The report indicated a communication gap between air traffic controllers after one of the runways was closed.

Over 4000 passengers' were at risk as a result. The Bengaluru-Kolkata flight carried 176 passenger and six crew, while the Bengaluru-Bhubaneswar flight carried 238 passengerss and six crew - a total of 426 passengers.

The matter was not recorded in any logbook and not reported by the AAI. "We are investigating and will take strict action against those responsible," a DGCA official said. The AAI runs air traffic control.