Summary
The Federal Aviation Administration (FAA) proposes to adopt a new airworthiness directive (AD) that is applicable to Rolls-Royce plc (RR) RB211 Trent 875, 877, 884, 892, 892B, and 895 series turbofan engines. This proposal would require initial and repetitive visual inspections of the intermediate pressure (IP) compressor rear stubshaft and IP turbine shaft for load-bearing spline flank wear, and replacement of these shafts if necessary. This proposal is prompted by reports of IP compressor rear stubshaft and IP turbine shaft load-bearing spline flank wear, revealed at inspection during overhaul. The actions specified by the proposed AD are intended to prevent the loss of drive between the IP turbine and the IP compressor, which could result in a turbine rotor overspeed condition, possible uncontained engine failure, and damage to the airplane.