Calcutta, Jan. 24: Flight schedules went haywire and thousands of passengers got stranded as heavy fog enveloped the runways at Calcutta airport this morning.
Flight operations at the Netaji Subhas Chandra Bose International airport were closed from 5am to 9.30am as visibility dipped to 50 metres.
In the morning, 23 flights were delayed by three-and-a-half hours on average. But around 40 more flights were affected through the day in a chain effect, a senior airport official said.
Two incoming flights had to be diverted as they were unable to land.
The Category II instrument landing system installed in 2007 allows flight operations at a minimum runway visibility of 350 metres.
Airport sources said the visibility today started dropping around 2.30am. In two and a half hours, it went down to 50 metres.
The fog started thinning around 6.30.
A Druk Air flight from Thimphu was the first plane to land at 9.27am. Air Indias Port Blair flight was the first to take off at 9.30, almost four hours behind schedule.
Jet Airways Delhi flight took off minutes later, also around four hours late.
Kingfisher Airlines Chennai-Calcutta flight was diverted to Guwahati at 8.30 and Air Indias Bangalore flight went to Bhubaneswar.
Both flights returned later in the day.
There was a huge congestion on the runway after flight operations resumed, causing further delays, said an official. The flights were lined up one after another for takeoff while others were landing.
Passengers had a harrowing time.
We arrived around five in the morning and then came to know that the flight operations were closed, said Vijay Bhurani, a Calcutta businessman going for a holiday to Delhi with his family on a low-cost carrier.
We had to wait for several hours and no refreshment was provided by the airline, he complained.
Passengers also alleged that there was no place to sit in the domestic terminal building as it was overcrowded.
Tour operators said many passengers were cancelling their morning tickets and rebooking on day or afternoon flights. This winter, lot of passengers are requesting for cancellation of morning flight bookings as they want to avoid fog delays, said Anil Punjabi of the Travel Agents Federation of India.
Earlier this winter, zero visibility stalled flights on two days. The weatherman said there would be fog in the city in the next two mornings, too.