A plane had less than six minutes’ worth of fuel left on a recent flight, forcing the pilot to issue a “Fuel Mayday” call.
The A320neo aircraft was unable to land in Delhi and was diverted to Lucknow around 420km away.
However, after visibility suddenly dropped above Lucknow, the pilots attempted to head to Prayagraj 30 minutes away, only to turn towards Lucknow again after seven minutes.
By this stage the jet was fast running out of fuel and had started eating into emergency reserves, prompting the “Mayday” call.
The weather cleared just enough for the plane to touch down in Lucknow, with only 200kg of fuel remaining – enough for five to six minutes’ flying time – a source told The Times of India.
A senior pilot told the publication: “It’s a miracle they landed.”
He called the decision to divert to Prayagraj instead of doing a fully automated landing at Lucknow “sacrilegious”.
The flying time from Mumbai to Delhi is around two hours, but Monday’s flight was airborne for close to four hours after circling Delhi for over an hour before attempting to divert twice.
Aviation regulator DGCA confirmed it has grounded the pilots involved, with a senior Vistara official confirming they have been “de-rostered” while the incident is being investigated.
A Vistara spokesperson told The Independent: “Flight UK944 operating Mumbai-Delhi on July 15, 2019, initiated a diversion to Lucknow due to bad weather over Delhi. However, over Lucknow, the visibility suddenly dropped and a safe landing was not possible.
“The crew then considered alternative airfields, including Kanpur and Prayagraj, to land in comparatively better weather conditions.”
They added: ”The unexpected drop in visibility at the destination 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.
“Safety of passengers and crew was kept at the highest priority throughout the flight.”
The flight finally touched down safely in Delhi at around 1.35am after refuelling at Amausi airport, having originally departed Mumbai at 2.40pm.