{"id":"F2006B07448","name":"AD/TPE 331/38 - Second Stage Turbine Wheel Assembly","slug":"ad-tpe-331-38-second-stage-turbine-wheel-assembly","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":49771,"registerId":"commonwealth-F2006B07448-current","compilationNumber":null,"startDate":"2026-04-02","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/TPE 331/38 - Second Stage Turbine Wheel Assembly","content":"---\nmeta-content-style-type: text/css\nmeta-content-type: application/xhtml+xml; charset=utf-8\nmeta-generator: Aspose.Words for .NET 22.10.0\n---\n\n?xml version=\"1.0\" encoding=\"utf-8\" standalone=\"no\"?>\n\nCOMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 106 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n \n\n![](image.001.png)  AlliedSignal (Garrett/AiResearch) Turbine Engines - TPE 331 Series\n\n \n\nAD/TPE 331/38 Second Stage Turbine Wheel Assembly 9/88\n\nDM\n\nApplicability: TPE 331 - 25; -43; -47; -55 and -61 series engines with second stage turbine wheels whose serial numbers are listed in the Requirement document.\n\n \n\nRequirement: Inspect (and replace if necessary) the second stage turbine wheel assy in accordance with Garrett S.B. TPE 331-A72-0577.\n\n \n\nCompliance: 1. For turbine wheels 0 to 650 hours time since new (TSN) prior to 700 hours TSN.\n\n \n\n2. For turbine wheels more than 650 hours TSN within 50 engine operating hours after 30 June 1988.\n\n \n\nBackground: This Directive is issued to remove from service second stage turbine wheel assemblies which have been manufactured incorrectly.\n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n","sortOrder":0}],"analysis":{"kimi_summary":{"_metrics":{"model":"kimi-k2.5","source":"moonshot-batch","completionTokens":1498},"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"The directive maintains its original narrow scope targeting specifically identified defective turbine wheel assemblies in the TPE 331 engine series. It has not expanded beyond the initial safety remediation for manufacturing defects."},"complexity_factors":["Single mechanical component targeted (second stage turbine wheel)","Simple binary compliance structure based solely on flight hours threshold","Only five specific engine series variants affected","Direct reference to only one external technical document","No exemptions, exceptions, or conditional clauses"],"plain_english_summary":"This CASA airworthiness directive mandates inspection and, if required, replacement of second-stage turbine wheels on specified AlliedSignal (Garrett/AiResearch) TPE331 engines that have wheels with serial numbers listed in the referenced service bulletin. It affects owners/operators of the TPE331-25, -43, -47, -55, and -61 series engines.\n\nInspections must be done by set TSN-based deadlines (soon for low-time wheels; within 50 hours after 30 June 1988 for high-time wheels) to remove a manufacturing-defective wheel that could fail in flight."}},"importantCases":[],"_links":{"self":"/api/acts/ad-tpe-331-38-second-stage-turbine-wheel-assembly","history":"/api/acts/ad-tpe-331-38-second-stage-turbine-wheel-assembly/history","analysis":"/api/acts/ad-tpe-331-38-second-stage-turbine-wheel-assembly/analysis","conflicts":"/api/acts/ad-tpe-331-38-second-stage-turbine-wheel-assembly/conflicts","importantCases":"/api/acts/ad-tpe-331-38-second-stage-turbine-wheel-assembly/important-cases","documents":"/api/acts/ad-tpe-331-38-second-stage-turbine-wheel-assembly/documents"}}