Aviation Dense fog impacts daily flight operations at Delhi Airport Updated : December 30, 2019 08:03 AM IST IndiGo and Spicejet have also alerted passengers about the delays in airlines’ operations and asked them to stay in touch with airlines’ staff. Three flights were diverted from Delhi airport on Monday morning due to heavy fog. Flights are operating at the airport under CAT III B conditions, which means that the runway visual range (RVR) is between 50 metres and 175 metres. Subscribe to Moneycontrol PRO at just Rs.33/- per month for the first year. Use code SUPERPRO. Limited period offer. Available on Web and Android.