Action
Final rule.
Summary
We are adopting a new airworthiness directive (AD) for certain Rolls-Royce plc (RR) RB211-Trent 875-17, 877-17, 884-17, 884B-17, 892- 17, 892B-17, and 895-17 turbofan engines. This AD requires inspection of the affected low-pressure (LP) turbine bearing support and exhaust case assembly and, if necessary, its replacement with a part eligible for installation. This AD was prompted by thin-walled LP turbine bearing support and exhaust case assemblies having been delivered into service. We are issuing this AD to prevent failure of the LP turbine bearing support and exhaust case assembly, which could lead to engine separation and damage to the airplane.