Over 100 flights were affectedtoday due to this winter's first dense fog which engulfed theIGI airport here disrupting air operation and causinginconvenience to passengers.
Flight operations virtually remained suspended for abouttwo hours, between 7 AM and 9 AM, after dense fog descended atthe airport. Runway visibility dropped suddenly from 700 m toless than 50 m on all three runways.
With runway visibility being far less than the requiredminimum limit of 125 m (for smaller aircraft) and 150 m (forbigger aircraft), no flights were taking off, an airlineofficial said, forcing the airline to hold back flightdepartures.
As flight operations remained standstill for two hours, itled to delay in schedule of over 40 flights which had acascading effect on the schedule of other flights.
Over 100 flights, during the day were delayed, threeflights including an international were diverted while threeflights were cancelled, airport sources said.
Situation started to improve after 8.30 AM when visibilityrose to 300 m. The general visibility on the main runway(which is the most preferred runway during foggy days) was 50m while the runway visibility was 75 m.
At one time, the runway visibility dropped to zero at oneend of the third runway.
"Delhi airport witnessed dense fog from 3.30 AM till 10 AMtoday. All the runway had CAT-IIIB and CAT-IIIC dense fog at 7AM when runway visual range suddenly dropped from 775-900 m tojust 75 m. It improved at 9 AM when the visibility on mainrunway first to 330 m and on third runway to 100 m at around10 AM," Airport MeT in-charge R K Jenamani said.
Fog cover, however, remained over the airport and city allthrough the day as more fog advanced from eastern side.
"It was a very sudden transition as till yesterday Delhiwas not having any fog. Even shallow fog or smog were missingfor last 42 days due to strong winds," Jenamani said.
Dense fog conditions is likely to start midnight tonightand visibility dip below 50 m at around 3 AM, he added.
Airport operator Delhi International Airport Limited(DIAL), alongwith all stakeholders like airlines, air trafficcontrol, ground handling staff and others, has taken a host ofmeasures to meet any situation arising due to fog.
Some of the measures include ATC scheduling slots fordeparture of flights in advance based on the MeT forecast andairlines prioritising their flights and plan boarding as perthe slot, which would reduce inconvenience to passengers.
DIAL and airlines has made adequate arrangement for foodand drinks to stranded passengers.