The recent cases of in-flight shutdown or engine failure in Pratt & Whitney-powered Airbus A320neos were the result of issues related to main gear box, the Directorate General of Civil Aviation (DGCA) said on Wednesday.

So far, the country has witnessed 12 cases of in-flight shutdown in the Pratt & Whitney-powered A320neos since their induction in March 2016 and most of these in-flight shutdowns and other related incidents have happened due to failure of “Number 3 Bearing” seal, failure of “Knife Edge Seal”, erosion of combustion chamber material, low pressure turbine rotor blades damage and issues relating to the main gear box, the regulator said.

"Out of the above causes, corrective action has been taken by P&W and the airlines in respect of all except issues relating to main gear box which is a recent phenomenon," DGCA said in a statement.

The aviation regulator was listing the outcome of the meeting that took place with top officials from Airbus, Pratt & Whitney, IndiGo and GoAir on Tuesday on the glitches affecting the operations of A320neo planes in the country.

DGCA also said that it has noted that the Inflight Shutdown cases on account of these NEO engines in India are at 0.02 per 1,000 engine flight hours, which is lower than the stringent global benchmark of 0.05 in-flight shutdown rates per 1,000 engine flight hours.

The urgent review meeting on Tuesday was called after a series of recent incidents involving Pratt & Whitney-engine run A320neos. The latest incident took place on January 3, whereby, IndiGo flight 6E 923 operating Chennai-Kolkata returned to Chennai shortly after takeoff due to a technical glitch.

While the airline maintained that there was no engine shutdown, sources said that the aircraft witnessed unusual vibration and a loud noise, after which the aircraft made the priority landing at Chennai airport.

This is three weeks after an A320neo of IndiGo made an emergency landing at Kolkata airport following reports of suspected smoke in the cabin. The video footage of 6E-237 flight was captured by passengers showing disturbing visuals of smoke in the cabin and then emergency evacuation of some passengers via slides at the back of the plane.

The regulator will now issue a safety advisory for A320neos next week after seeking input from the US aviation regulator FAA, airlines, aircraft and engine manufacturer.

It is important to recall here that the A320neo aircraft is extremely significant in the domestic aviation space as not only is IndiGo the largest client of A320neo with a combined order of 430 such aircraft, but with GoAir's order-book of around 144 such planes, half of the country's incoming planes are of A320neo make.

First Published:Jan 9, 2019 3:19 PM IST