Airworthiness Directive · Amendment 39-21135 · Engine mount section
Rolls-Royce Deutschland Ltd & Co KG (Type Certificate Previously Held by Rolls-Royce plc) Turbofan Engines
Superseded. A later AD replaced this one: AD 2023-04-14. Comply with the one in force.
This AD applies to Rolls-Royce Deutschland Ltd. & Co KG (RRD) (Type Certificate previously held by Rolls-Royce plc) Trent XWB-75, XWB-79, XWB-79B, and XWB-84 model turbofan engines.
The FAA is adopting a new airworthiness directive (AD) for certain Rolls-Royce Deutschland Ltd. & Co KG (RRD) Trent XWB-75, XWB- 79, XWB-79B, and XWB-84 model turbofan engines. This 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 AD requires initial and repetitive inspections of the LPC OGV outer mount ring assembly and, depending on the results of the inspections, possible replacement of the LPC OGV outer mount ring assembly. The FAA is issuing this AD to address the unsafe condition on these products.
(1) For affected RRD Trent XWB turbofan engines with 1,700 flight cycles since new (FCSN) or greater as of the effective date of this AD:
(i) Within 300 flight cycles (FCs) after the effective date of this AD, perform a fluorescent penetrant inspection (FPI) of the LPC OGV outer mount ring assembly.
(ii) Use Accomplishment Instructions, paragraph 3.A. or 3.B., as applicable, of Rolls-Royce plc (RR) Alert Non-Modification Service Bulletin (NMSB) Trent XWB 72-AK188, Revision 2, dated December 17, 2019, to perform the FPI of the LPC OGV outer mount ring assembly.
(iii) Thereafter, perform repetitive FPIs of the LPC OGV outer mount ring assembly within 1,000 FCs after the previous inspection.
(2) For affected RRD Trent XWB turbofan engines with fewer than 1,700 FCSN as of the effective date of this AD:
(i) Before exceeding 2,000 FCSN after the effective date of this AD, perform an FPI of the LPC OGV outer mount ring assembly.
(ii) Use Accomplishment Instructions, paragraph 3.A. or 3.B., as applicable, of RR Alert NMSB Trent XWB 72-AK188, Revision 2, dated December 17, 2019, to perform the FPI of LPC OGV outer mount ring assembly.
(iii) Thereafter, perform repetitive FPIs of the LPC OGV outer mount ring assembly within 1,000 FCs after the previous inspection.
(3) If, during any FPI required by paragraph (g)(1) or (2) of this AD, an LPC OGV outer mount ring assembly discrepancy is detected, as defined in the Accomplishment Instructions, paragraph 3.A. or 3.B., of RR Alert NMSB Trent XWB 72-AK188, Revision 2, dated December 17, 2019, repeat the FPI within the interval specified in Accomplishment Instructions, paragraph 3.A. or 3.B., of RR Alert NMSB Trent XWB 72-AK188, Revision 2, dated December 17, 2019.
(4) If, during any FPI required by paragraphs (g)(1) through (3) of this AD, an LPC OGV outer mount ring assembly is rejected as a result of the FPI, as defined in the Accomplishment Instructions, paragraph 3.A. or 3.B., of RR Alert NMSB Trent XWB 72-AK188, Revision 2, dated December 17, 2019:
(i) Before further flight, replace the LPC OGV outer mount ring assembly with a part eligible for installation.
(ii) [Reserved]
For the purpose of this AD, “a part eligible for installation” is a new LPC OGV outer mount ring assembly that has not been previously installed on an engine.
The reporting requirements in the Accomplishment Instructions, paragraph 3, of RR Alert NMSB Trent XWB 72-AK188, Revision 2, dated December 17, 2019, are not required by this AD.
The aircraft, engines and makers this AD names, by the model designations in its text. A model listed here may still be outside the AD's serial ranges.
