John Joseph Bianco

Gentlemen, I am the Principal Maintenance Inspector for Empire Airlines based in Hayden Idaho. On 11/15/2012, Empire Airlines, Inc. reported that one of their ATR 42's experienced what they believed to be an engine fire on the #1 engine.(PW121) The engine was shutdown and the aircraft landed safely. An engine tear down report recently received from Pratt & Whitney Canada revealed that a fracture of one LPT blade near the platform was by fatigue propagation from the trailing edge until final fracture by overload. The fatigue fracture most likely originated at the trailing edge tip from a casting anomaly that also resulted in the formation of numerous cracks. Summary: Pratt & Whitney report number: 13GS00001 high pressure turbine vane ring segment (HPT)---Heat eroded Low Pressure Turbine (LPT)---Fractured Based on the engineering analysis contained in this report I have to ask why this particular engine model was omitted from the affectivity list for the proposed AD?