New Delhi, Feb 8 (PTI) Schedule of around 100 flightswent haywire as operations came to a virtual standstill forabout three hours today after dense fog enveloped the IndiraGandhi International airport.
Most of the morning flights, scheduled to departbetween 6 AM and 9 AM, were either delayed or had to berescheduled as the visibility at the runway hovered between 75and 100 metres, airport sources said.
The required minimum range of runway visibility for anaircraft to operate is 125 metres for small aircraft while itis 150 metres for large aircraft.
National carrier, Air India, cancelled its flight toLeh and rescheduled 17 others, while Jet Airways cancelledthree flights and rescheduled five others.
There was no diversion of flights, an airport officialsaid.
The visibility started to drop around 2:30 AM in themorning forcing airport authorities to implement lowvisibility procedures (LVP) at around 3:16 AM on the newrunway.
No LVP was implemented on the main runway till 5:20 AMin the morning, the official said, adding so there were nodiversion of flights coming to Delhi as they were able to landat the airport using various Categories of instrument landingsystem (ILS).
A total of 117 domestic and international flightsoperated using various categories of ILS during the LVPperiod, which was terminated at 10.50 AM.
During the seven hours and 34 minutes of LVP on thenew runway and five hours and 30 minutes on the main runway,51 flights landed with CAT-I ILS, 22 with CAT-III A and 44using CAT-III B ILS, the official said.