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 AD/TPE 331/33 Amdt 3 Second Stage Turbine Rotor/Seal Interference 10/87 TX Applicability: TPE 331-25, -43, -47, -55 and -61 series engines as listed in the Requirement Document. Requirement: 1. Accomplish interim rotational check in accordance with (IAW) GTEC SB TPE 331-A72-0522 Revision 2 Para 2.A.(1). 2. Radiographically inspect the second stage turbine rotor and seal plate assemblies in accordance with GTEC SB TPE 331-A72-0522, Rev 2 dated 1 July 1987. Para 2. A(2)(3) and (4). Note: FAA AD 86-08-06 Amdt 39-5275 refers to SB TPE 331-72-0522 Rev 1. Compliance: For Item 1 above: Within 25 operating hours after 3 August 1987 and thereafter at 25 hourly intervals until the initial radiographic inspection IAW Item 2 is completed. Note: Initial radiographic inspection is completed when the radiographic film has been submitted and acceptable analysis results received from Garrett. For Item 2 above: Unless already accomplished, initially within 100 engine operating hours after 31 August 1986 or prior to achieving 500 engine operating hours since last engine overhaul whichever is the later, and thereafter at intervals not exceeding 300 hours of engine operation. Background: This Directive is amended to reflect the manufacturers Alert Status of SB TPE 331- A72-0522 Rev 2 which also includes the TPE 331-61A engine in applicability. SB TPE 331-A72-0522 Rev 2 also makes reference to Alert SB TPE 331-A72-0560 which is the Requirement Document for new AD/TPE 331/35 which is issued concurrent with this Directive.