Action
Notice of proposed rulemaking (NPRM).
Summary
We propose to adopt a new airworthiness directive (AD) for certain Rolls-Royce plc (RR) RB211-Trent 875-17, RB211-Trent 877-17, RB211-Trent 884-17, RB211-Trent 884B-17, RB211-Trent 892-17, RB211- Trent 892B-17, and RB211-Trent 895-17 turbofan engines that have not incorporated RR modification 72-J195 in production or RR Service Bulletin (SB) RB.211-72-J195. This proposed AD was prompted by inspection of RR Trent 800 engines returned from service that revealed flame erosion and axial cracking on the aft face of the stage 3 disk rim of the high-pressure compressor (HPC) stage 1-4 rotor disks shaft. This proposed AD would require machining the HPC stage 3 inner shroud, inspecting the HPC stage 1-4 rotor disks shaft, and replacing the HPC stage 1-4 rotor disks shaft if found defective. We are proposing this AD to prevent uncontained failure of the HPC stage 1-4 rotor disks shaft, damage to the engine, and damage to the airplane.