Summary
The FAA proposes to adopt a new airworthiness directive (AD) for certain Rolls-Royce Deutschland Ltd. & Co KG (RRD) Trent XWB-75, XWB-79, XWB-79B, and XWB-84 turbofan engines. This proposed AD was prompted by analysis by the manufacturer of the low-pressure compressor (LPC) outlet guide vane (OGV) assembly and LPC OGV outer mount ring assembly. The analysis predicted that when the front engine mount is in the fail-safe condition, the most highly stressed LPC OGV outer mount ring assembly has a life that could be substantially less than one shop visit interval. This proposed AD would require initial and repetitive inspections of the OGV outer mount ring assembly and, depending on the results of the inspections, possible replacement of the OGV outer mount ring assembly. The FAA is proposing this AD to address the unsafe condition on these products.