Visibility conditions at Palam airport dropped to zero disrupting air operations. Nil visibility descended on the airfield in the wee hours today and continued till past 1000hr. The visibility has since improved and the RVR ( runway visual range) has become better at facilitating normal flying operations. However, the cascading effect of the delayed operations, since morning, will continue for some more time.
Yesterday also, the horizontal visibility had dropped to zero, between 6 and 8.30 in the morning leading to flight restrictions. The weekend ahead is not going to be any better and rather very dense fog is expected for longer durations. Air travellers may please make a note of it and cater for the exigencies.
At Delhi airport, three runways are equipped with ILS ( Instrument Landing System), to negotiate poor visibility conditions. Runways 11, 28 and 29 comply with CAT-III operations under bad weather conditions, albeit with their own limitations. CAT-III is invoked during poor visibility conditions largely due to fog but can be introduced for any other aviation hazard, as well, as reducing visibility. CAT-III comes into practice when the visibility plummets to under 200 mtrs. CAT-III A comes when the RVR drops to 175mtrs or more and CAT-III B is called for the RVR between 75 and 175 mtrs. The most difficult and decisive stage is CAT-III C when the RVR sinks to 50 meters. The airfield is generally closed for operations when the RVR goes less than 50 meters. The limitations for the aircraft operations underline visibility to be a
minimum of 50 meters for landing and at least 125 meters for take off, at any given point of time, subject to a decision height of 15 meters. For CAT-III operations, both the man and machine, have limitations and need strict compliance of the procedure and capability.
Delhi has recorded the lowest minimum temperature of 7°C, today morning. This is the lowest in the last 2 weeks, since 21st Dec 2024. Also, parts of Delhi have registered fifth consecutive cold day conditions. Even, the airport observatory Palam recorded the day maximum of 13.5°C, over 5°C below the normal. The minimum temperature, yesterday and today was nearly stuck at 6.5°C, a shade below the normal. The minimum temperature is likely to rise over the weekend due to changes in winds. However, the day temperature is likely to lower because of clouding in association with the approach of western disturbance. A brief and light spell of rain is quite likely over the city and outskirts on 06th Jan.
Image Courtesy: Canva
