ON THURSDAY, fog reduced runway visibility at the Delhi Airport to 150 metres -- enough for flights to land and take off using the recently installed Category III B Instrument Landing System. But that did not happen: nine flights were diverted, two cancelled, a dozen rescheduled and two dozen delayed.
ON THURSDAY, fog reduced runway visibility at the Delhi Airport to 150 metres -- enough for flights to land and take off using the recently installed Category III B Instrument Landing System. But that did not happen: nine flights were diverted, two cancelled, a dozen rescheduled and two dozen delayed.
Three Indian (Airlines) flights took off in the morning, assisted by the landing system. But no flights, including those with pilots trained for CAT III B ILS, landed at the airport for about 10 hours from midnight, pointing to the reluctance of the pilots to use the system. Some pilots said they did not exactly trust the CAT III B ILS. They give the example of an incident on December 25. A Canadian Airlines flight, which landed at the airport with the help of CAT III B ILS, ended up with damaged wings.
"It dented our confidence. Many of us are CAT III C trained -- we can land in zero-visibility. But we are not sure if the system here is calibrated properly," said a pilot of an international airline.
A few years ago, the International Federation of Airline Pilots Association had declared the Delhi Airport unsafe. "The AAI has failed to satisfy us whether the ground-based aids for CAT III B ILS are as per the International Civil Aviation Organisation standards," said the pilot. Another pilot, who retired with an experience of 19,000 flying hours, said: "CAT III B is over three decades old.
Most airports, including those in China, have moved on to satellite-based navigation but we still continue with ground-based approach aids."
AAI officials, however, defended the landing system. They alleged that Indian and Air-India pilots want risk allowance to operate in low-visibility conditions.