India's aviation regulator on Monday extended the deadline for IndiGo and GoAir to replace 60 Pratt and Whitney (PW) engines on their A320neo planes from May 31 to August 31, as supply chain has been impacted due to the novel coronavirus-induced lockdown.

The PW engine-powered A320 neo planes in IndiGo and GoAir fleets have been facing glitches both mid-air and on-ground since their induction way back in 2016.

On January 13, the Directorate General of Civil Aviation (DGCA) had said the unmodified PW engines do contain an unsafe condition, which is prone to undesirable outcomes and therefore, needs to be dispensed with.

On Monday, the regulator said: "We took a call a couple of days back and instructed both the airlines. Both taken together about 60 engines are yet to be replaced and the obvious reason was Covid-19 impact and the resultant lockdowns."

Supply chains and production lines got impacted due to the Covid-19 pandemic and in turn, disturbed the process, it added.

"Keeping all this in view, we have extended the deadline by three months; up to 31st of August 2020. Also, we instructed that for current times, aircraft with both engines modified should be flown and this should not be difficult as the curtailed operations are likely to last for some more time," the regulator said.

Four Air Turn Back (ATB)/Inflight Shut Down (IFSD) events were witnessed on Airbus A320Neo aircraft operated by Indigo in a week during October 2019 due to the failure of third stage LPT (low pressure turbine) blades.