Action
Notice of proposed rulemaking (NPRM).
Summary
We propose to adopt a new airworthiness directive (AD) for all Rolls-Royce plc (RR) RB211-535E4-37, RB211-535E4-B-37, RB211-535E4-C- 37, and RB211-535E4-B-75 turbofan engines. This proposed AD was prompted by RR updating the low-cycle-fatigue life analysis for the low pressure turbine (LPT) stage 2 discs. This proposed AD would require removal of affected parts using a drawdown plan. We are proposing this AD to prevent LPT stage 2 disc failure, which could result in uncontained engine damage and damage to the airplane.