Airbus brought the issue to the European aviation agency's attention, a spokesperson said, and the company has outlined safety recommendations for airlines until Pratt & Whitney can fix or replace the engines.
The problem could become much bigger if the engine supplier cannot find a quick fix, as the delivery schedule of future A320neo aircraft will likely be seriously affected in that case. "But we feel it was the best decision in the interest of our safe and reliable operations", IndiGo said in a statement.
In brief, the European Aviation Safety Agency (EASA) issued, as usual, an emergency airworthiness directive in which it explains that "several engine stops in flight as well as takeoff interruptions have been reported".
EASA has said that if an aircraft with both engines being affected has completed three flight cycles after the issuance of the airworthiness directive, it should not operate.
"The passengers have also been given choice of full refund as well".
Airbus too has issued an alert, saying these aircraft should not be used till further instructions.
According to the airline officials, they have withdrawn the three A320neo planes from service w.e.f. February 9.
"This is something done hand-in-hand with the regulators to put some teeth behind the recommendations that we made", an Airbus spokesperson said.
Airbus said P&W is investigating the root cause of this new finding with the full support of it.
This is the second time that IndiGo has been forced to ground planes because of P&W engine problems. "To date, 113 P&W powered A320 neo family aircraft are flying with 18 customers", Airbus said in a statement.
It was not immediately clear if the recent aft modification is related to the geared turbofan engine family's other known durability issues.
According to civil aviation industry analyst, out of 100 plus A320neo planes, delivered with PW1100G - JM engines globally, 11 aircraft have this particular configuration on both engines and around 21 aircraft have this particular configuration on one of their engines.
The airline added that passengers affected due to flight cancellations have been accommodated in "our other connections and flights of other airlines".