Hyderabad and four Airport Authority of India-run airports -- Bhopal, Bhubaneshwar, Ranchi and Raipur -- are upgrading their infrastructure for improved low-visibility operations by end of this year.
At present, these airports are equipped with a CAT I Instrument Landing System (ILS), which enables aircraft to land with 550 metres visibility. An upgrade to CAT II ILS is underway and will enable aircraft to land in conditions with 350 metre visibility.
A Hyderabad airport spokesperson said one side of the main runway is being upgraded to CAT II and the work is expected to be complete by December. “Upgradation to CAT III has also been planned,” she said.
A CAT IIIB ILS allows landing in 75-metre visibility and is installed at Delhi airport, among others. The minimum visibility required for aircraft take-off is 125 metres during low-visibility operations.
Hyderabad airport is the fourth busiest in the country, and handles around 230 flights daily. Though Hyderabad doesn’t experience dense fog - the kind seen in North India, that reduces visibility to zero - 35 flights were diverted from Hyderabad due to low visibility between December 25 to January 5.
Bhubaneshwar, too, rarely sees visibility drop below 550 metres, but upgrades are being planned in view of traffic growth in the cities.
Runway lighting system
Upgradation from CAT I to II essentially involves enhancements in the runway lighting system, with lights installed on the runway centre line and touchdown zone. Even the approach lights are of a higher intensity. Besides this, the area where ILS equipment is installed needs to be graded and made free from obstacles, especially during a low-visibility operation. For a CAT III operation the requirements get even more stringent.
“We are constructing parallel taxiways and a rapid exit taxiway that that will reduce the runway occupancy time and help augment capacity. Alongside, the runway is being re-carpeted and the existing instrument landing system is being upgraded to CAT II,” said Bhubaneswar airport director Prasanna Pradhan.
Currently, we see around 90-100 flights daily and handle around 14,000 passengers,” he added.