Flight delays, cancellations due to fog: Can airlines do something more?

Flight schedule getting off during winter is an annual affair in several parts of the country due to prevailing dense fog conditions but airlines can’t do much even at airports equipped with instrument landing system to help the passengers stuck at airport.

There have been several videos of thousands of passengers stuck at airports in extreme cold with no updated information from the airlines on future schedule of the flight operations. Airlines claim to take all measures as per protocol to cater to passengers in such situation.

Delhi airport has already issued an advisory that flights which are not compliant with the navigation system CAT III, would get affected during the prevailing fog conditions. However, even CAT-III compliant flights get impacted during zero visibility situation.

In a zero visibility scenario, even the airport with instrument landing systems (ILS) has to stop operations. Zero visibility in aviation parlance means anything (even 1 meter below) the mandatory requirement of 75 meters for CAT III (B) landing and 125 meters for take-off. The ILS helps in landing but not taxing on the runway during fog.

Airports in India are upgrading their instrument landing systems (ILS) to improve safety and efficiency as dense fog has been a recurring issue in the northern and northeastern regions of the country during winter months.

According to industry players, there are only six airports—Delhi, Lucknow, Jaipur, Amritsar, Bengaluru and Kolkata—in the country that have the necessary infrastructure and technology to handle low visibility operations (CAT III) during dense fog. Flights in about 40 airports in the northern and northeastern regions of the country have been impacted during the winter season.

Delhi, a major domestic hub, experiences frequent flight disruptions during fog. In dense fog, flights are often diverted to alternate airports like Jaipur, Ahmedabad, Lucknow, Nagpur, Bhopal, and Indore.

“Majority of the new aircraft are equipped with CAT III technology but airport infrastructure needs upgrade to facilitate the same,” says the Captain of a major airline.

IndiGo’s, country’s largest airline by market share, daily flight operations stand at over 2,100 out of over 80 domestic airports with fog impacting over 40 airports and approximately 650 flights on various sectors.

“Delhi airport’s all four runways are equipped with CAT III landing but with 1500 flight moments daily where every 1 min a flight takes off/land, during fog the duration shifts to 3 min per flight. If the visibility went down further like an incident on Jan 14 last year, where runway visibility was below zero for 5-6 hours, the capacity gets blocked and pile up happens,” adds the Captain.

Most Air India and IndiGo pilots are trained for CAT (III) landings, which means the captain has 500 flight hours and the first officer has 300. However, issues arise when heavy fog causes delays and complications.