ATCs blameless in Charkhi Dadri tragedy, claims counsel

The Airport Authority of India denied that any of its air traffic controllers on duty at the Indira Gandhi International Airport on November 12, the day a Kazakh aircraft hit a Saudi Boeing over the Charkhi Dadri sub-division of Haryana, was overworked or fatigued.

Continuing submissions for the second day before the Justice R C Lahoti court of inquiry which is investigating the collision, AAI counsel Air Commodore N A K Sarma said the tone and clarity of the ATC transmissions and the promptness of response to calls or reports from any of the aircraft in contact at the time indicate the controllers were alert, composed, competent and functioned with involvement.

The fact that the same approach controller did not harry him but actually enhanced coordination and removed any possible confusion, the AAI counsel contended.

He submitted that the IGI airport's 'single corridor' has not contributed to the accident as such a facility for entry and exit existed at many international airports. If aircraft adhere to ATC clearances and if proper radar control and safety measures are provided, he said a single corridor is quite safe.

Even when two different uni-directional (one-way) corridors at different heights are provided, aircraft would still have to cross each other's paths in the terminal area. Any violation of orders in such a case too could be catastrophic, Air Commodore Sarma said.

Laterally separated entry and exit routes are primarily meant to optimally use the airspace capacity to to ensure smooth flow of traffic and enhance safety. However, if an aircraft violates the assigned course and strays to the left or right, a collision is likely, he said.

As part of the new modernisation programme, a segment of the corridor to the west is to be made uni-directional. It will be put into operation once air traffic services at Delhi and related navigational aids defining the corridors are upgraded, the AAI counsel submitted.

Any impression that secondary radar or any other equipment was lying uninstalled during November, he said, was incorrect. The navigational aids and other facilities available at the IGI airport are published information and therefore is common knowledge for all operators, including Kazakstan Airlines, he said.

Absence of sophisticated or most up-to-date systems, such as monopulse secondary radar, does not justify carelessness or a casual altitude on the part of the flying crew. Instead it calls for self-imposed flight discipline and strict observance of clearances and standards, the counsel stated, adding the Kazakh government's contention in this regard held no relevance since the primary radar system at the airport provided surveillance of air-traffic within 60 nautical miles of Delhi.

While the Kazakhstan government wanted India to install the most sophisticated facilities at airports, its aircraft lacked basic mandatory equipment foreign airplanes flying over Indian airspace are expected to have, Air Commodore Sarma said.

If all of Kazakhstan's suggestions were followed, he added, the IGI airport could not handle 20 movements an hour, nor would Heathrow be able to handle about 90 movements per hour.

Arguing about the miniumum distance of 1000 feet required between aircraft in India, the AAI counsel contended that neither any ICAO provision nor common practice demanded a larger separation. Even under severe turbulence, a vertical separation of 1,000 feet was adequate, he said, adding that the vertical separation of 1,000 feet was in conformity with ICAO standards and was sufficient to ensure safe, efficient and smooth flow of air traffic.