Delhi is getting dangerously close to experiencing a major air disaster. There have been a number of near-misses over Delhi's air space in the past few months and the reasons are growing air traffic, old operation procedures and overworked air-traffic controllers (ATCs).
In the past five months, one near-miss has occurred in a month on average, with most of them happening during landing or take-off from the Indira Gandhi International Airport (IGIA). The Directorate General of Civil Aviation (DGCA) is now planning to make major changes to bring things under control.
Sources at the airport and in DGCA, however, said DGCA and the Airports Authority of India, which manages the air traffic control, are probing into these incidents but apart from taking some ATCs off the roster, nothing concrete has been achieved.
"The Standard Operating Procedures (SOPs) have not been revised in the past 10 years while air traffic has increased rapidly. The existing procedures are poorly designed,” said a senior air-traffic controller.
He said at IGI Airport, one runway should be dedicated for arrivals and the other for departures. In most incidents of near-misses, two aircraft have taken off from the two runways of IGIA in the same direction. As the runways — primary runway (28/10) and secondary runway (27/09) — are not parallel, if two aircraft take off in the direction of Dwarka, their flight paths converge at a distance of 1.5 nautical miles. In many incidents, aircraft have come as close as 1 nautical mile, while the minimum distance should be 5 nautical mile.
“International airlines prefer landing and taking off from the main runway because it is longer. At peak hours, the main runway is sometimes used for both arrival and departure while the secondary runway is used only for take-offs,” said another ATC.
“The air-misses are a lesson learnt,” Director General Kanu Gohain told the Hindustan Times. “We are looking into the mitigating factors and the standard operating procedures are being improved,” he said.
Although Gohain said the incidents had decreased in July, he admitted better coordination between ATCs manning different runways was required to avert any mishap.
“The procedures are in the process of change and the major change will be dedicating one runway to arrivals and another to departures. The groundwork is ready for the plan to be implemented,” a DGCA source said. Simultaneous usage of both runways started from April 2006 and has recently been extended from nine to 10 hours. Controllers say simultaneous use puts more pressure on them, even though they are already overburdened due to lack of manpower.
At present, Delhi’s air-space is divided in two sectors – area west and area east. ATCs say ideally there should be four sectors for north, south, east and west for better management. “However, the present manpower is not sufficient for even the two sectors,” said an ATC.