Aviation safety watchdog DGCA has asked IndiGo to replace both the engines on 40% of its planes in the next 90 days. The directive issued on Friday is for 97 Pratt and Whitney-powered planes.
Of these 97 planes, IndiGo will have to equip 23 planes with one modified engine by November 19.
"The operator must ensure that all these aircraft are provided with Modified LPT by 31/1/2020 at all costs. In case it is not done, such aircraft shall not be allowed to fly with unmodified Engines," the DGCA said in an order issued to IndiGo on Friday.
The move follows four incidents of air turn back or in-flight shutdown in the past one week. An incident each occurred on October 24, 25, 26 and 30. The airline has been facing engine-related problems ever since it started inducting A320 NEO planes in 2017 fitted with P&W engines, forcing the regulator to take corrective measures from time to time, but the latest directive is the strictest action it has taken so far on the matter.
Review maintenance and safety data
“The operator must ensure that all these aircraft are provided with modified low pressure turbine (LPT) by 31/1/2020 at all costs. In case, it is not done, such aircraft shall not be allowed to fly with unmodified engines,” the Directorate General of Civil Aviation (DGCA) said in a press statement after meetings during week with officials from IndiGo, Pratt and Whitney and Airbus to review maintenance and safety data.
While GoAir, too, has the same engine variant on its A320 Neo planes, today's order is only for IndiGo. A DGCA official explained that this was because IndiGo has seen 12 such incidents in 2019, while GoAir has seen none. According to the official, IndiGo recorded four incidents in 2018 and three in 2017.
Replacing both the engines on 98 planes with the modified or repaired version entails a supply of 196 engines by January 31. While IndiGo says nearly half of these engines have already been repaired.
“IndiGo currently operates 98 A320 NEO family aircraft with around 45% of its engines modified. We are working with both P&W and Airbus on mitigation so that we have enough modified spare engines by January 31, 2020,” the airline said in a statement.
But safety experts say that engine availability will be a major obstacle in meeting a tight deadline of 90 days, and that a real solution would be to ground the entire fleet of P&W-powered planes till repaired engines are installed.
Expert opinion
"There is no way PW can supply so many engines in such a short time, which will force the DGCA to keep extending the deadline. There is also a very serious issue of stress and fatigue affecting the pilots who have to be prepared for a situation where their might be an engine shutdown, which have now become frequent. The regulator is actually delaying on what is the only action it should be taking, which is to ground the entire fleet of A320 Neos with PW engines," aviation safety expert Captain Mohan Ranganathan told The Hindu .
However, if it wants to keep the planes flying the DGCA must ensure that a Captain has atleast 2,000 hours of flying and a co-pilot 1,000 hours so that the cockpit crew has the experience to respond to an incident, Mr. Ranganathan explained.
In what may seriously impact IndiGo's expansion plans, the DGCA has unequivocally asked it to halt induction of new plans and focus its effort on fit operations of its existing planes. "You may like to stagger or defer your future induction plan and procure sufficient number of modified Engines to keep the existing fleet in operation," the order adds.
The airline had on Wednesday announced an order of 300 planes of A320 family of aircraft.
