Action
Final rule.
Summary
We are adopting a new airworthiness directive (AD) for all Rolls-Royce plc (RR) model RB211 Trent 768-60, 772-60, and 772B-60 turbofan engines. This AD was prompted by low-pressure (LP) compressor blade partial airfoil release events. This AD requires a one-time ultrasonic inspection of LP compressor blades that had accumulated more than 2,500 flight cycles (FC) since new. We are issuing this AD to prevent LP compressor blade airfoil separations, engine damage, and damage to the airplane.