Airworthiness Directives; Rolls-Royce plc (RR) RB211 Trent 500 Series Turbofan Engines

The FAA is superseding an existing airworthiness directive (AD) for RR RB211 Trent 553-61, 553A2-61, 556-61, 556A2-61, 556B-61, 556B2-61, 560-61, and 560A2-61 turbofan engines. That AD currently requires removing certain serial-numbered intermediate pressure compressor (IPC) drums, part number (P/N) FK30102. This AD requires removing those same IPC drums, and requires a new reduced life limit for all other IPC drums, P/N FK30102. This AD results from an RR engineering assessment that it is necessary to reduce the cyclic lives of the other drums with the same P/N. We are issuing this AD to prevent uncontained loss of IPC stage 1 blades, which could result in damage to the airplane.