Airworthiness Directives; AlliedSignal Inc. TPE331 Series Turboprop and TSE331 Turboshaft Engines

摘要

This document proposes the adoption of a new airworthiness directive (AD) that is applicable to AlliedSignal Inc., (formerly Garrett Engine Division, Garrett Turbine Engine Company and AiResearch Manufacturing Company of Arizona) TPE331 series turboprop and TSE331 turboshaft engines. This proposal would require replacement or radiographic inspection, and replacement , if necessary, of certain third stage turbine stators with serviceable parts. This proposal is prompted by a report of an outer band weld that cracked subsequent to a radiographic inspection required by a previous AD. The actions specified by the proposed AD are intended to prevent third stage turbine wheel separation due to thermal fatigue cracking and shifting of the third stage turbine stator, which could contact the third stage turbine wheel and result in an uncontained engine failure and damage to the aircraft.