Air operations at the IGI airport here remained disrupted due to dense fog for the second consecutive day on Friday, hitting the schedule of over 50 flights.

Around 29 domestic and 14 international flights were delayed while six were diverted to other cities like Jaipur, Ahmedabad.Five domestic flights were cancelled after fog enveloped the airport, an airport official said.

On Thursday, about 100 flights were badly affected due to dense fog.

The runway visibility started to drop late Thursday night when fog started to descend on the airport. The general visibility dipped to zero while the runway visibility hovered between 50 to 100 metres, forcing the airport authorities to implement low visibility procedures for flights to operate using CAT—III B instrument landing system (ILS).

Though some landing took place using CAT—III B ILS, which helps an aircraft to land when the runway visibility is around 50 metres, departure of flights started only in the morning when the runway visibility increased to over 100 metres.

According to an airport official, departures would become normal only when the visibility increases to 350 metres, the required minima for the flights to take off.

Flight operations remained suspended for about three hours on Wednesday night and on Thursday morning after the visibility dropped to less than 50 metres.

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