Action
Notice of proposed rulemaking (NPRM).
Summary
We propose to supersede airworthiness directive (AD) 2012-04- 01 that applies to all Rolls-Royce plc (RR) RB211-Trent 800 model turbofan engines. AD 2012-04-01 requires removal from service of certain critical engine rotating parts based on reduced life limits. Since we issued AD 2012-04-01, RR has further revised the life limits of certain critical engine rotating parts. This proposed AD would make additional revisions to the life limits of certain critical engine rotating parts. We are proposing this AD to correct the unsafe condition on these products.