Vistara says the flight could have managed only 10 more minutes in the air before running out of fuel

Highlights Vistara plane was unable to land in Delhi due to poor weather conditions

It then went to Lucknow, where visibility also suddenly dropped

Pilots considered alternate airfields including Kanpur and Prayagraj

A Vistara flight from Mumbai to Delhi with 153 on board had a close shave on Monday when it was diverted to Lucknow because of bad weather conditions and landed with very low fuel levels.

Vistara Airlines has told NDTV that the flight could have managed only 10 more minutes in the air before running out of fuel. The aircraft had barely 300 kg of fuel left when it touched down at Lucknow airport. With the fuel situation onboard increasingly critical, the pilots declared a "Fuel Mayday", indicating the seriousness of their situation to the Air Traffic Control.

In a statement on Wednesday, the airline said visibility suddenly dropped over Lucknow and a safe landing was not possible. The crew considered other landing possibilities, including Kanpur and Prayagraj.

"En route Prayagraj, Lucknow ATC informed the crew that the weather in Lucknow had improved significantly following which the crew decided to return to Lucknow due to better passenger and aircraft support," the airline said in its statement.

"The unexpected drop in visibility at the designated alternate was the main reason why the aircraft ended up in a low-fuel situation despite carrying excess fuel over and above the required Flight Plan Fuel as per regulations," it said, adding that the safety of passengers and crew was "kept at the highest priority throughout the flight".

Vistara statement on UK944 diversion, July 15. pic.twitter.com/HrdQfCBeKU — Vistara (@airvistara) July 17, 2019

Aviation experts have told NDTV that an Airbus A-320 NEO flight on the Mumbai-Delhi sector usually lands with enough fuel for approximately 60 extra minutes of flight. This extra fuel carried onboard is used if the aircraft has to divert to alternate airports.

On this occasion, the A-320 NEO aircraft was unable to land at the Delhi airport due to poor weather conditions and was diverted to Lucknow, but visibility suddenly dropped over Lucknow and the pilots on board considered alternate airfields including Kanpur and Allahabad.

The civil aviation watchdog, DGCA, has grounded a Vistara pilot over the incident, news agency ANI has reported.