• Crew trained to operate in low visibility on flights to fog-prone airports

Pre-arranged” accommodation and transportation for crew members so they are available as soon as the condition improves

Airlines are planning several measures to reduce delays during winter when fog plays havoc with flight schedules across India.

The Calcutta airport authorities said they are preparing to reduce disruptions triggered by fog in the city as well as at other airports.

The Category III-B instrument landing system, which was installed at the Calcutta airport in early 2018, allows flights to land even when the runway visual range is as low as 50m.

However, visibility often dips below 50m in winter because of fog, stalling flights.

On January 15, 238 flights to and from the city were delayed and 41 were cancelled because of fog at the Calcutta airport and many other cities, including Delhi. Altercations broke out between passengers and the airline staff.

IndiGo and Air India said they have made plans to minimise delays during winter.

“Qualified low visibility operations (LVO) crew are scheduled for flights during fog-prone periods, ensuring safety and operational reliability,” said a spokesperson for IndiGo. “Conditional captains are excluded from rosters during the fog season to minimise risks and maintain consistency in operations.”

Conditional captains are those with less than 100 hours of experience as a flight commander, a pilot said.

“Often flights trying to land at an airport in low-visibility conditions get diverted because the crew are not certified to operate in such conditions. So, proper planning while preparing the roster can help avoid such inconveniences,” the pilot said.

IndiGo said the crew will be strategically positioned near airports to reduce delays caused by transportation challenges during foggy conditions. “Accommodations and transportation are pre-arranged for crew, ensuring they are readily available to operate flights as soon as conditions improve,” the airline said.

“Based on historical data and strategy, IndiGocarries additional fuel to account for holding patterns and taxi delays, reducing the need for diversions and gate returns.”

Air India sources said it has strengthened its systems to ensure timely alerts are sent to passengers. “We have mobilised all resources for faster response to any fog disruption. Alternative airports have been identified and equipped for smooth handling of passengers... if there is any flight diversion,” said an airline source. “Air India is well-equipped with a large pool of CAT III-certified aircraft and pilots.”

Calcutta airport sources said a dedicated team has been set up to coordinate with airlines and other agencies to handle fog delays.

“Non-essential work on the airfield will be stopped and unnecessary vehicles removed to ensure faster movement of aircraft amid low visibility,” said an airport official. “This will reduce delays to some extent,” he said.

Airport officials said the airlines should deploy more personnel in the terminal when there are major delays and hundreds of passengers are stranded.