Rolls-Royce has identified premature wear in the intermediate pressure compressor (IPC) in a “small number” of Trent XWB-84 engines following inspections performed during regular shop visits, the company said Tuesday. Approaching their first scheduled shop visits after four or five years of service on the Airbus A350, none of the engines have experienced any abnormal in-flight operation, said Rolls. However, the company added it would inspect all other Trent XWB-84 engines that have flown a similar number of hours “as a precaution.”
Rolls-Royce insists it does not expect the problem to create “significant” customer disruption or material cost, given the limited scale of additional work needed to address the wear during existing shop visits, together with the availability of replacement parts and spare engines. The company noted it decided to issue its statement to address any potential speculation that might result from an upcoming EASA airworthiness directive (AD).
Just over 100 Trent XWB-84s have operated in scheduled service for four to five years. After inspecting most of them, Rolls found signs of wear on an average of one or two IPC blades in a minority of the turbofans, the company reported, adding that it took the precaution of sampling a number of younger Trent XWB-84 engines and found no unexpected wear.
“The Trent XWB-84 has experienced the smoothest entry into service of any widebody engine we have developed,” said Rolls-Royce civil aerospace president Chris Cholerton. “Engines now coming in for overhaul have traveled the equivalent of 350 times around the world, with no unplanned maintenance. It is reassuring to see that our proactive inspection regime has enabled us to identify and swiftly address this issue and minimize any potential impact on our customers.”
Rolls-Royce said the IPC blade problem in the XWB-84s bears no relationship with the much-publicized travails of the Trent 1000 engine powering the Boeing 787. Last month the company reported “good progress” on fixing durability problems with that troubled engine, adding that it has achieved the target of single-digit numbers of aircraft grounded by the end of the second quarter.
Rolls said it has introduced certain solutions on a “fast-track basis” to improve the Trent 1000’s in-service durability. More than 99 percent of the flying fleet has received an improved intermediate pressure turbine blade. Meanwhile, engineers continue to fit Trent 1000 TEN and Package C engines with redesigned IPC blades, which the company expects to make available for the Package B engines in the fourth quarter. Rolls also reported that it should complete the Trent 1000 TEN and Package C blade roll program by the end of next year. For the Package B and C engines, it has upgraded more than 50 percent of the fleet with improved high-pressure turbine blades.
Rolls continues endurance testing a final durability issue with the Trent 1000 TEN's high-pressure turbine blades, identified during a “rigorous root cause investigation and design process,” according to the company. “We are now over three-quarters of the way through this test and remain on track for its incorporation into the fleet by the end of H1 2021,” it reported.