Summary
The FAA proposes to adopt a new airworthiness directive (AD) for GE CF6-80A series turbofan engines with a high-pressure turbine rotor (HPTR) stage 1 disk, part number (P/N) 9367M45G06, installed. This proposed AD would require removing any HPTR stage 1 disk, P/N 9367M45G06, before exceeding 2,075 cycles-since-new (CSN). This proposed AD results from an error by GE that incorrectly cited a cyclic life of 12,600 CSN for the HPTR stage 1 disk, P/N 9367M45G06. We are proposing this AD to prevent the HPTR stage 1 disk from exceeding its part life which could cause fatigue cracks to start and grow. These cracks could result in a possible uncontained disk failure and damage to the airplane.