Tata-Singapore Airlines joint venture airline Vistara and budget carrier AirAsia India are unlikely to get the Directorate General of Civil Aviation (DGCA)'s approval for CAT-IIIB operations in low visibility during the fog season this year, sources have said.
In a CAT-IIIB operation, an aircraft can land in visibility as low as 50 metres, while the normal minimum visibility required for take off from Indira Gandhi International Airport (IGIA) here is 125 m.
IGIA is the only domestic airport equipped with CAT-IIIB technology.
"Both Vistara and AirAsia India might not get CAT-IIIB this year," DGCA sources said on Sunday. Apart from other domestic airports, the two carriers have flight operations from Delhi as well.
Sources also said while another private carrier, Jet Airways had already received DGCA approval for CAT-IIIB operations, a decision on Gurgaon-based SpiecJet's application was expected shortly.
To conduct low-visibility landings, an airline requires certification for aircraft and pilots, who need to undergo ground training, simulator training and flying under the supervision of examiners.
Pilots operating flights under such weather conditions also need to undergo checks and supervised flying every six months to retain their ratings.
DGCA issues certification to an airline after it demonstrates a stipulated number of simulated low-visibility landings.
In the norms, airlines are required to deploy only CAT-IIIB compliant planes and trained crew for flying out of those airports in the country which face dense fog during winter.
Lucknow, Jaipur and Amritsar would be upgraded to CAT-IIIB from the coming winter, sources said.
Besides, Raipur, Bhubaneswar, Varanasi, Indore, Udaipur and Vadodara would be on an extended watch for diversion of flights, they said.