Airworthiness Directive · Amendment 39-12129 · Pratt & Whitney Canada (PWC) Model PW305 and PW305A Turbofan Engines
Pratt & Whitney Canada (PWC) Model PW305 and PW305A Turbofan Engines
Pratt & Whitney Canada (PWC) Models PW305 and PW305A turbofan engines with stage 4 low pressure turbine (LPT) disks, part numbers (P/N's) 30A1457 and 30A1499. These engines are installed on but not limited to British Aerospace BAe. 125 1000A, BAe. 125 1000B, Hawker 1000, and Learjet 60 series airplanes.
This amendment adopts a new airworthiness directive (AD), applicable to Pratt & Whitney Canada (PWC) Models PW305 and PW305A turbofan engines, that requires removing stage 4 low pressure turbine (LPT) disks from service before exceeding new, lower cyclic life limits. This amendment is prompted by the results of a spin pit test analysis which indicate that the stage 4 LPT disk does not have full published life. The actions specified by this AD are intended to prevent LPT disk failure resulting from premature cracking of the LPT disks, which could result in an uncontained engine failure and damage to the airplane.
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.
