A taxiway at Kolkata airport that has been in place for nearly three years has got a go-ahead from the aviation regulator and will now be used as a rapid exit taxiway. This will help save 8-10 precious seconds of runway occupancy time by arriving aircraft, clearing the main runway for departing flights.
“We have got clearance to declare taxiway R as rapid exit taxiway for flights arriving from Madhyamgram-end or north of the runway. This runway is in use for over seven months a year and will allow planes to exit at high speed. At present, planes have to either brake hard to reduce speed before turning into taxiway R or roll ahead and exit the runway from taxiway C further down the runway. Either way, planes stay longer on the runway and therefore delay its use by another flight. With the commissioning of taxiway R as rapid exit taxiway, planes can move off the primary runway at high speed,” explained Kolkata airport air traffic control (ATC) general manager R S Lahauria.
Planes touch down at 250-300kmph and need to brake to exit the runway. When there is a rapid exit taxiway, it can turn into the taxiway at 90kmph. Or else, it has to slow down to 15kmph before exiting it. The shorter the occupancy time of the runway, the more aircraft the airport can handle. At Kolkata airport, departing flights use the slot between two arrivals to make the dash for takeoff.
Sources said though taxiway R has been in existence and use for sometime now but it was not categorized as rapid exit taxiway as it did not have the requisite length and the angle of turn into taxiway R was rather sharp.
To address the issues, the authorities did two things. First, since the secondary runway is not in use when the primary runway is in operation, they managed to convince DGCA that a part of it can be considered a segment of the taxiway. Second, they widened the shoulders of the taxiway to allow planes to turn into it at a less acute angle of 135° instead of 120°. “We are now preparing an SOP for controllers and pilots so that aircraft using taxiway R to vacate the runway at high speed does not encounter a conflict with an aircraft using taxiway A,” Lahauria said.
The SOP is critical as departing aircraft currently use taxiway A to head to the primary or even the secondary runway. Once taxiway F that is further away from the twin runways is extended northward, planes will use it to head for takeoff instead of taxiway A.
“DGCA has given the nod to work on taxiway A. Work on the project has begun and will lead to major improvement in traffic movement at Kolkata airport. It will also save time and fuel for departing aircraft,” said Lahauria.
There is a proposal to create two more rapid exit taxiways, one of them at the other side of the runway for use when planes land from the Rajarhat-end.
Source: Times of India