Airworthiness Directive · Amendment 39-10746 · Pratt & Whitney PW4000 Series Turbofan Engines
Pratt & Whitney PW4000 Series Turbofan Engines
Pratt & Whitney Models PW4052, PW4056, PW4060, PW4060A, PW4062, PW4152, PW4156A, PW4158, PW4460, PW4462, PW4164, and PW4168 turbofan engines, with 2nd stage high pressure turbine (HPT) rotating airseals, Part Numbers (P/N) 50L156 or 50L195, installed. These engines are installed on but not limited to Boeing 747 and 767 series, McDonnell Douglas MD-11 series, and Airbus Industrie A300, A310, and A330 series aircraft.
This amendment adopts a new airworthiness directive (AD), applicable to certain Pratt & Whitney PW4000 series turbofan engines, that requires fluorescent penetrant and eddy current inspections of 2nd stage high pressure turbine (HPT) rotating airseals for cracks, removal from service of cracked parts, incorporation of improved 2nd stage HPT rotating airseals, and modification of 2nd stage ring segments and vane clusters to increase cooling flow and reduce stress as terminating action to the inspection requirements. This amendment is prompted by reports of 2nd stage HPT rotating airseal cracking. The actions specified by this AD are intended to prevent 2nd stage HPT rotating airseal cracking, which could result in an uncontained engine failure and damage to the aircraft.
The aircraft, engines and makers this AD names, by the model designations in its text. A model listed here may still be outside the AD's serial ranges.
