Mumbai: American engine-maker Pratt & Whitney has started supplying new engines to its largest customer in the country, IndiGo, helping it put back into operations some of the grounded A320 Neo planes.

The Gurgaon-based airline has taken off the ground two A320 Neos after it has received two new engines from P&W this month and more such grounded aircraft are expected to resume flying soon as it expects new engine deliveries to improve, official sources said.

Recurring engine glitches have forced the airline to ground nine of its A320 Neos and cancel over 600 flights between late June and early July. The airline currently has 140 A320s, of which 23 are P&W engine-powered A320 Neos.

“Pratt & Whitney (P&W) has supplied two new engines to IndiGo, following which two of its eight grounded A320 Noes have resumed flight," a source told PTI in Mumbai.

Queries sent to both IndiGo and P&W seeking confirmation on the issue remained unanswered. The largest airline had taken off nine A320 Neos from its fleet in the June quarter owing to engine issues.

However, one of these planes was made operational later.

As of today, only six A320 Neos are grounded, said another source in the civil aviation authority. Indigo had cancelled 667 flights in 13 days between 21 June and 3 July due to grounding of some planes.

While 504 flights were cancelled between 21 June and 30 June, the remaining 163 were cancelled on the first three days of July. The new engines have been delivered to IndiGo after the regulator DGCA asked P&W last month to expedite new engine supplies following the grounding of these planes by the two budget carriers-IndiGo and GoAir.

The Wadia group-run GoAir has also grounded three of its five A320 Neos due to engine issues. “If India is giving you (P&W) so much business, when the new engines come, you allocate them to India. they have promised that by end-September, the situation will be normal," a senior DGCA official had said earlier.

With two A320 Neos back into flying, IndiGo has now only six of such planes grounded, said another source.

IndiGo president and whole-time director Aditya Ghosh had told analysts after the June quarter earnings on 31 July that “there were days when we had to ground as many as nine A320 Neos due to lack of spare engines. While we do receive certain compensation from Pratt & Whitney for these groundings, the operational disruptions are quite challenging and we are not happy with that situation."

Official sources also claim that IndiGo was being compensated for the revenue loss its each aircraft is suffering due to the grounding.

“IndiGo is getting compensation from P&W for the revenue loss its each grounded aircraft is suffering every day due to non-operation," the official said.

But both the airline and P&W did not respond on this claim. IndiGo had cancelled 48 and 44 flights on 21 June and 22 June respectively, and 48 and 43 the next two days, which rose to 50 flights on 25 June and 45 the next day.

With nine of its A320 Neos on the ground as of 27 June, Indigo was forced to cancel 61 flights that day, and it was followed by cancelling of another 53 and 61 flights on 28 June and 29 June. On 30 June, it had cancelled 50 flights.

Similarly, on 1 July, 50 flights were cancelled and on 2 July, the cancellations rose to 53 flights, which came down to 51 cancellations on the next day.

“Our schedule was planned in June itself pertaining to non-availability of these aircraft for July, August and September. The affected passengers are already accommodated with suitable options," the airline had said on the massive flight cancellations.