IndiGo has been instructed by the civil aviation regulator to change engines on 16 of its Airbus A320neos, following three instances of aircraft turning back. The regulator has warned the airline the aircraft would have to be grounded if the changes are not completed in the next 15 days.
IndiGo has a fleet of 245, including 89 A320neos. These are powered by Pratt & Whitney (PW) engines and have been facing low-pressure turbine issues, main gearbox failure, and engine vibration, resulting in schedule disruptions. While modifications have been carried out, the regulator wants IndiGo to take more steps.
“We have decided that all aircraft with unmodified LPT engines, which have clocked more than 2,900 hours, have to be fitted with one modified LPT engine in the next 15 days,” said Director General of Civil Aviation Arun Kumar.
The action follows the analysis of the three incidents between October 24 and 26 due to LPT failure. A team of Directorate General of Civil Aviation officials met the airline’s senior management on Monday. “IndiGo has been instructed to ensure no Airbus A320neo which has two PW 1100 series engine of more than 3,000 hours engine life each should be operated. IndiGo has been given a fortnight to comply with the instructions,” said Kumar.
While the IndiGo management had last week said it saw improvement in engine performance and reduction in snags, the regulator took a strict view and possible grounding of planes.
In a statement on Monday, IndiGo said, “We are continuing to work with the authorities and will take necessary action, as required, going forward.”
“We can see significant overall improvement. The in-flight shut-down rate has come down to 0.01 per 1,000 engine flight hours,” the airline’s Chief Operating Officer Wolfgang Prock-Schauer informed analysts after the second-quarter results.
He added, “The regulatory requirement laid down by the US Federal Aviation Administration and European Aviation Safety Agency is 0.05 and we are within the regulatory limit.” He did not specify the engine’s previous shut-down rate.
Prock-Schauer said many of the issues related to the engine have been fixed and the airline is on track to resolve the rest. These pertain to LPT, main gearbox, and engine vibration.
He said all the A320neo planes delivered after May have the necessary modification which addresses LPT failure.
“The main gearbox issue has been fixed and all the required software changes have been done,” he clarified.
Global regulators do not call for maintenance action if engine vibration is below a certain threshold, but the airline has a taken a cautious approach over the issue and is taking all necessary action, Prock-Schauer said.