Airworthiness Directives; CFM International CFM56-2, -3, -3B, - 3C, and -5 Series Turbofan Engines

This amendment revises an existing airworthiness directive (AD), applicable to CFM International (CFMI) CFM56-2, -3, -3B, -3C, and -5 series turbofan engines, that currently requires repetitive magnetic chip detector (MCD) inspections and removal from service of certain No. 3 bearings. This amendment removes the requirement for MCD inspections for certain No. 3 bearings if the bearing has 6,000 or more hours time in service since new, extends the removal from service date for certain No. 3 bearings, changes the inspection interval for certain No. 3 bearings, deletes a specific No. 3 bearing part number, and replaces reference to specific maintenance manuals with service bulletins. Other requirements of the current AD remain unchanged and are carried over into this revised AD. This amendment is prompted by additional data that demonstrates a reduced bearing failure rate after a period of time in service; therefore, an acceptable level of safety can be maintained with a relaxation of some of the current AD requirements. The actions specified by this AD are intended to prevent a No. 3 bearing failure, and a subsequent inflight engine shutdown.