Airbus believes it will still be able to start delivering the A320neo before the end of this year, despite not having a specific timeframe for resuming test flights with the Pratt & Whitney-powered variant.
Flight-testing with the two PW1100G-equipped aircraft – F-WNEO and D-AVVA – has been “paused” since early May, says Airbus, after discovery of a component manufacturing flaw.
Airbus has not indicated when the aircraft might restart their flight campaign, stating only that it is “confident” of returning them to testing “in the coming weeks”.
“We remain on track to begin aircraft deliveries in 2015,” the airframer adds.
Airbus has previously stated that it would start delivering the PW1100G-powered A320neos from October.
“We had findings during flight testing,” it says. “Together with our partner Pratt & Whitney we are currently analysing the situation.”
Airbus says it understands that the findings relate to a “minor part” – a retaining ring holding a seal.
“It is the mission of flight-testing to find issues before entry into service to ensure the highest maturity from day one,” it adds.
Airbus programmes chief Didier Evrard, speaking in Toulouse in late May, indicated that the seal was located between the high-pressure compressor and the rest of the engine.
The seal is retained by clips, he said, and there had been “some production batches” which had shown “slightly more deviations when running, when exposed to temperature”.
Evrard said he believed a thermal treatment problem was behind the finding, and said that the retaining rings would be replaced.
Another source familiar with the situation says the issue relates to a bracket beneath the combustor which holds the seal in place but which became disengaged, adding that this has been traced to the manufacturing process rather than the component design.
Pratt & Whitney says that it “understands” the cause of the flight-testing findings and the company is “addressing them”.
It is similarly confident that testing will restart in the “coming weeks” and that it is ready to support service entry in the “fourth quarter”.
Testing has continued with a third A320neo, F-WNEW, which is fitted with the rival CFM International Leap-1A engine. It carried out its maiden flight on 19 May.