Budget airline Go First cancelled several flights scheduled for May 3, 4 and 5 as the Wadia group-owned carrier blamed aircraft engine maker Pratt & Whitney for the 'serial failure' in supplying engines for its A320neo fleet.

The non-supply of engines by U.S.-based aerospace major Pratt & Whitney has grounded close to 50% of Go First's A320neo fleet, costing the airline ₹10,800 crore in lost revenues and additional expenses.

"We regret to inform you that due to operational reasons, Go First flights scheduled for May 3, 4 and 5 have been cancelled," the low-cost carrier said in a tweet.

"A full refund will be issued through the original mode of payment shortly," the airline said.

Meanwhile, passengers who had booked Go First flights took to social media to complain that their flights have been cancelled without prior notice. The airline said cancellations were due to 'operational reasons'.

"Extremely unprofessional behaviour of @gofirst airlines. Cancelled my flight from Delhi to Hyderabad due to operational reasons without informing me 24 hours in advance. No refund or next booking options," wrote Twitter user Prakhar Shukla.

Another Twitter user Anuj Sharma, whose works as a tour operator, said the he had booked 17 tickets from Leh to Jammu in Go First. His flight was scheduled for May 3 morning at 8:30 am. "But now I received a call from GoFirst the flight is cancelled. How we will manage it," Sharma wrote on the microblogging platform.

Another user, Shravan Gupta, whose bio mentions him as a solar module manufacturer, says he had connecting flights and the airline 'ruined' his summer vacation. "How am I suppose to cancel all my connecting bookings; they first didn't turn up on call for 20mins then says we can only offer refund," Gupta wrote on Twitter.

"We have our summer vacation and now How am I suppose to proceed with my vacation. You just ruined everything. Advance deposited everywhere. Other flights not going to refund us. Worst service worst carrier.. Ruined our plans and shamelessly not responding," he added.

This comes days after aviation regulator DGCA (Directorate General of Civil Aviation) said that Go First received zero passenger complaints in March. Vistara and Go First were the only airlines which did not receive passenger-related complaints in March, as per DGCA data.

The low-cost airline has reportedly filed an emergency petition in Delaware court against aircraft engine maker Pratt & Whitney, seeking enforcement of two arbitral awards that order a Pratt & Whitney partner to immediately provide the carrier with the serviceable engines that the business says it needs to stay aloft.

"If Pratt does not immediately comply with the awards, there is a significant risk that Go First will go out of business and be forced to declare bankruptcy," the airline said, as reported by U.S.-based legal news service Law 360. As the award recognised, Go First requires a minimum of 103 engines from Pratt for normal operations, yet only approximately 56 currently are serviceable, it added.

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