{"id":"F2006B07421","name":"AD/TPE 331/13 - Short Torsion Shaft Spline Wear - Inspection","slug":"ad-tpe-331-13-short-torsion-shaft-spline-wear-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":49675,"registerId":"commonwealth-F2006B07421-current","compilationNumber":null,"startDate":"2026-04-02","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/TPE 331/13 - Short Torsion Shaft Spline Wear - Inspection","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 331/13 Short Torsion Shaft Spline Wear - Inspection 3/86\n\nApplicability: TPE-331-1-100F, -101B, -101E, -101F, -101J, -101L, -101Z, -151A, -151G, -151K. TPE-331-2-201A, -201C.\n\n \n\nTPE-331-2UA-203D.\n\n \n\nDocument: AiResearch TPE-331-72-0024, Rev. 3, or AD/AIR-T/15A. Compliance:  As detailed in reference document.\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\n \n\n \n\n \n\n \n\n \n","sortOrder":0}],"analysis":{"kimi_summary":{"_metrics":{"model":"kimi-k2.5","source":"moonshot-batch","completionTokens":1951},"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"The directive maintains its original narrow scope addressing specific mechanical wear in specific TPE 331 engine models. There is no indication of scope expansion beyond the original safety issue."},"complexity_factors":["Single operative requirement directing compliance with an external technical document","No interpretation section or defined legal terms","Straightforward applicability list (specific engine model numbers) without conditional logic or exceptions","No procedural steps embedded in the instrument itself — all technical detail deferred to referenced manufacturer documentation"],"plain_english_summary":"This CASA Airworthiness Directive mandates inspections for wear on the short torsion shaft spline in specified AlliedSignal (formerly Garrett/AiResearch) TPE331 turbine engines, using the manufacturer’s referenced service bulletin procedures. \n\nIt applies to owners/operators of those engine models and is safety-critical: unchecked wear can cause engine failure, and non‑compliance renders the aircraft unairworthy."}},"importantCases":[],"_links":{"self":"/api/acts/ad-tpe-331-13-short-torsion-shaft-spline-wear-inspection","history":"/api/acts/ad-tpe-331-13-short-torsion-shaft-spline-wear-inspection/history","analysis":"/api/acts/ad-tpe-331-13-short-torsion-shaft-spline-wear-inspection/analysis","conflicts":"/api/acts/ad-tpe-331-13-short-torsion-shaft-spline-wear-inspection/conflicts","importantCases":"/api/acts/ad-tpe-331-13-short-torsion-shaft-spline-wear-inspection/important-cases","documents":"/api/acts/ad-tpe-331-13-short-torsion-shaft-spline-wear-inspection/documents"}}