As Mumbai battles with flight delays courtesy the ongoing runway revamp at the airport, the city’s worsening air quality could bring more bad news for fliers.

Apprehending thick smog (a combination of smoke and fog) cover to affect visibility at the airport this winter, weather sensors installed along the runway will now also convey data on smog presence to the air traffic control (ATC).

Air-borne pilots have also been allotted codes to access the weather data.

The weather sensors, installed in May, are already conveying data on wind speed, rainfall and visibility. Though Mumbai does not feature in the fog-prone zone like Delhi and other northern cities but increasing air pollution is likely to cause smog leading to further flight delays this winter, said climate scientist.

“We are not equipped like Delhi airport to tackle smog because the winter season here is very different. The problem could send morning peak hour schedules off gear,” said an ATC official requesting anonymity, as he is not authorised to the talk to the media.

“Thick smog cover is likely to affect visibility throughout this winter,” said R. V. Sharma, deputy director (western region) of the India Meteorological Department (IMD). “Air pollutants cling to the sky when temperature drops leading to drop in visibility,” he added.

Worried by the disturbing projection, the weather bureau for the first time would be sending smog updates to the ATC officials at Mumbai airport.

“We will send them regular updates to keep pilots informed on fluctuating visibility,” added Sharma.

A study released by the New York-based Desert Research Institute in August showed that Mumbai tops in vehicular emission amongst 20 other Indian cities because of congested roads and fewer vehicles running on compressed natural gas. The study also revealed that the city’s vehicle population jumped by 10 to 12 per cent last year.

Already 80 per cent flights leaving the city are running late by 35 to 40 minutes since October 1 when the airport’s secondary runway shut for maintenance till January.