A Pratt and Whitney (PW) engine on IndiGo's A320neo aircraft, which was heading from Chennai to Hyderabad on Monday, suffered a snag, according to a source privy to the development.
"The A320neo aircraft, which had the call sign 6E-6215, landed safely in Hyderabad. High vibration was observed in the second PW engine post-landing," the source said.
In a statement, IndiGo said, "Flight 6E-6215 was operating from Chennai - Hyderabad on Dec 2. Post arrival at Hyderabad, the pilot reported a momentary engine vibration caution during flight. The aircraft was withdrawn from operations. Necessary maintenance checks are in progress."
The source said the affected PW engine would be replaced.
Aviation regulator DGCA on November 25 had instructed IndiGo to ground an old A320neo family aircraft with an unmodified PW engine for every new A320neo plane added to its fleet to prevent large-scale cancellation of flights from January 31 onwards.
On November 1, the Directorate General of Civil Aviation (DGCA) had told IndiGo to replace old PW engines - under both wings of 97 A320neo family aircraft - with modified engines "at all costs" by January 31 or they would be grounded.
The regulator was afraid that from January 31 onwards, it would have to ground many IndiGo planes as they would be left with unmodified PW engines, leading to multiple flight cancellations across the country.
The regulator's November 25 directive was likely to affect the low-cost carrier's expansion plans as it would have to deploy each new A320neo plane, which was joining its fleet from here onwards, on the routes that would be vacated due to grounding of an unmodified A320neo plane.
The PW engine-powered A320 neo planes in the fleets of IndiGo and GoAir have been facing glitches both mid-air and on-ground since their induction way back in 2016.