COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 106 CIVIL AVIATION SAFETY AUTHORITY

SCHEDULE OF AIRWORTHINESS DIRECTIVES

AlliedSignal (Garrett/AiResearch) Turbine Engines - TPE 331 Series

AIRWORTHINESS DIRECTIVE

For the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (AD) under subregulation 39.1 (1) of CAR 1998. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.

AD/TPE 331/56 Second Stage Turbine Stator 12/2001

Applicability: TPE331-1, -2, -3, -5 and -6 series engines incorporating a second stage turbine stator assembly part number (P/N) 894528-1, -2, -3, -5, -6, -10 and -11.

Note 1: Stator assemblies P/N 894528-10 and 894528-11 which have been flow tested and reidentified in accordance with Honeywell Service Bulletin TPE331-72-2085RWK are no longer -10 or -11 stators and are therefore not applicable.

Requirement: Replace second stage turbine stator assembly part number (P/N) 894528-1, -2, -3, -5,

-6, -10 and -11 in accordance with Honeywell Service Bulletin TPE331-A72-2082.

Note 2: The FAA has advised they are working to issue an Airworthiness Directive mandating this requirement.

Compliance: At next access to the second stage turbine stator assembly, but no later than 3100 engine hours in service since last turbine section inspection.

This Airworthiness Directive becomes effective on 28 November 2001.

Background: This Directive has been issued to address reports of six uncontained failures of the second stage turbine wheels in TPE331-1, -2, -3, -5 and -6 series engines incorporating a second stage turbine stator assembly part number (P/N) 894528-1, -2,

-3, -5, -6, -10 and -11. The uncontained turbine failures were initiated by fatigue damage to the second stage turbine stator inner seal support, resulting in turbine wheel rub and uncontained rotor failure.

Neville Probert

Delegate of the Civil Aviation Safety Authority 23 October 2001

The above AD is notified in the Commonwealth of Australia Gazette on 7 November 2001.