Kolkata: Flight operations at NSCBI airport in Kolkata were disrupted for sometime on Wednesday morning as visibility turned low due to dense fog, officials said.

West Bengal Governor C V Ananda Bose’s visit to Farakka in Murshidabad district in a BSF helicopter was also cancelled due to poor visibility, Director of Netaji Subhas Chandra Bose International (NSCBI) airport, Pravat Ranjan Beuria, said.

Besides, four flights to Kolkata – three domestic and one international – had to be diverted to other airports. The departure of 18 domestic flights and two international ones from Kolkata to various destinations were also delayed, he said.

There were four delayed arrivals, the official said.

Flight operations did not take place to and from the airport between 4.18 am and 6.16 am on Wednesday, the director said, adding, low visibility procedures (LVP) were declared at 4.38 am.

The Air Traffic Control (ATC) declares LVP when visibility falls below 800 metres, and ‘Follow-Me’ vehicles guide aircraft to their stands when visibility is extremely poor.

The LVP is also activated when the cloud ceiling is below 200 feet.

The procedure involves coordination among the airport operator, air traffic control and pilots to manage flights safely and minimise disruptions, Beuria said.

“These ensure that aircraft are able to land, taxi and take off safely, using advanced navigation systems and ground lighting,” he said.