Summary
This document proposes the supersedure of an existing airworthiness directive (AD), applicable to Pratt & Whitney JT8D-200 series turbofan engines, that currently requires periodic inspection of fan blades for locked rotors and foreign object damage (FOD), unlocking of shrouds if necessary, lubrication of fan blade shrouds, and dimensional restoration of the fan blade leading edge. In addition, that AD requires installation of improved design fan blades as terminating action for the inspections. This action would reduce the lubrication interval, and require removal of rotors that experience repeat lockups within 225 cycles in service. This proposal is prompted by reports of 7 fan blade failures since publication of the current AD. The actions specified by the proposed AD are intended to prevent fan blade failure, which can result in damage to the aircraft.