Mid-air collision averted near Chandigarh

Once it was airborne, its crew was directed by the Chandigarh Air Traffic Control (ATC) to ascend to, and maintain, “Flight Level 115” (11,500 feet) for the journey to Delhi. A couple of minutes after the King Air crew attained this position, it noticed an aircraft four miles ahead, approaching it from the opposite direction at virtually the same radial and height.

Piloted by Captain Suresh and moving at a speed of 600 km per hour, it was an IA Airbus A-320 ona routine flight (IC 485) from Delhi to Amritsar via Chandigarh and back, with 145 passengers, one infant and seven crew members on board.

In a situation like this, the standard operating procedure requires both aircraft to steer clear of each other’s way, by turning right. But when the King Air pilot, Wing Commander Bhushan Nanda, flying at 400 km per hour, found no sign from the Airbus of either spotting the 8-seater or altering its course, he made an instinctive decision to veer towards the left and prevented a collision with the Airbus and crossed it at 100 yards’ distance.

The passengers of the Airbus, however, remained completely oblivious of the development.

While the King Air pilot confirmed the incident, the IA Airbus pilot Captain Suresh told The Indian Express from his residence in New Delhi that he did not see any aircraft in the vicinity of the Airbus. Captain Suresh, however, confirmed that he was spoken to on the subject by the Chandigarh ATC, but declined to give anydetails.

The Chandigarh ATC, it is learnt, had directed the Airbus pilot to maintain an altitude of 12,500 feet when it crossed over from the Saharanpur ATC’s jurisdiction into Chandigarh ATC’s airspace.

When the King Air crew reported the incident and the height of the Airbus, the Chandigarh ATC maintained that the Airbus was directed to maintain “Flight Level 125” (12,500 feet).

On being asked by the Chandigarh ATC, the Airbus crew confirmed their altitude of 11,500 feet, and claimed that they had descended to this level following the ATC’s instructions.

“It is likely that the Airbus crew mistook for its own, the height allotted to the King Air,” commented a source. “But, then, there is no scope for any misunderstanding in aviation,” he added.

As a standard practice, the Chandigarh ATC sealed the tapes which had the conversations between the control tower and the two aircraft. While the authorities at Delhi as well as Chandigarh, were orally apprised of the incident yesterday, a writtenreport was submitted to the ATC here today by the officials of the aviation department of Haryana.

The ATC segregates all reciprocal air traffic by maintaining a vertical distance of at least 1,000 feet between any two aircraft. Also, an aircraft on a landing course is directed to descend, only when it is confirmed that an outgoing aircraft has crossed its position.

The flights between Chandigarh and New Delhi fly over Naraingarh and Sarsawa. Though the Naraingarh and Sarsawa ATCs monitor and report overhead traffic, only Chandigarh and Delhi ATCs are authorised to issue directives to the pilots.

The Airbus pilot was not grounded after questioning and the flight continued on its next leg to Amritsar, indicating that the Cockpit Voice Recorder (CVR) of the Airbus was not removed or sealed. The CVR records all conversations of last 30 minutes in the cockpit and is a crucial aid for the investigation and analysis of any mishap.

This near-collision between the Airbus and the King Air aircraft overNaraingarh has occurred two years after the worst mid-air disaster in aviation history, at Charkhi Dadri in Haryana. On November 12, 1996, 351 persons were killed when a Saudi Airlines Boeing 747 collided with a Kazakh IL 76. Since then, over half a dozen cases of near-hits have been reported in the country.