Indian low-cost carrier IndiGo has grounded seven of its Pratt & Whitney PW1100G-powered Airbus A320neos, with reports suggesting that a tax change is delaying replacement powerplants.

Flight Fleets Analzyer shows that the affected aircraft bear the registrations VT-ITG, VT-ITN, VT-ITF, VT-ITJ, VT-ITK and VT-ITM. IndiGo operates 128 A320s, 22 of which are of the re-engined variant.

Media reports say VT-ITS is the seventh unit grounded. Flight tracking websites show that the aircraft's last flight was on 8 July.

IndiGo owns -ITG, -ITS and -ITJ. The rest are owned by lessors including Avolon Aerospace Leasing and Goshawk.

IndiGo did not respond to FlightGlobal's queries, but local media reports indicate that there are also issues with a change in the country's goods & service tax from 1 July. This effects the tax treatment of imported aircraft and engines.

“We have faced some issues with the neo engine, causing operational disruptions. Both P&W and Airbus are working to address the issues," an IndiGo spokesperson is quoted as saying in a local report. "We continue to receive the necessary operational and technical support including the provision of spare engines to help mitigate the operational impact on us."

In March, India’s Directorate General of Civil Aviation (DGCA) identified the first known incident involving the gearbox of the PW1100G geared turbofan engine on the A320neo. A “main gearbox failure” caused one of 42 premature engine removals so far of PW1100G-powered A320neos, according to the DGCA. The failure was “detected as a metal chip warning”.

There were also another 41 premature engine removals caused by two known issues with the PW1100G, including 28 attributed to distress in a carbon-air seal for the No. 3 bearing and 13 caused by degraded combustion chambers.

Source: Cirium Dashboard