Summary
This document proposes the supersedure of an existing airworthiness directive (AD), applicable to certain Rolls-Royce, plc. (R-R) RB211 series turbofan engines, that currently requires removing from service intermediate pressure (IP) compressor stage 6-7 rotor shafts that exceed reduced cyclic life limits. This action would further reduce cyclic life limits and introduce new reduced cyclic bands for rework. This proposal is prompted by additional stress analysis conducted following failure of an IP compressor stage 6 disk. The actions specified by the proposed AD are intended to prevent an uncontained engine failure due to rupture of an IP compressor stage 6-7 rotor shaft.