{"id":"F2006B07256","name":"AD/T53/8 - Second Stage Power Turbine Rotor Disc - Rework","slug":"ad-t53-8-second-stage-power-turbine-rotor-disc-rework","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":49156,"registerId":"commonwealth-F2006B07256-current","compilationNumber":null,"startDate":"2026-04-02","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/T53/8 - Second Stage Power Turbine Rotor Disc - Rework","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 (Lycoming) Turbine Engines - T53 Series\n\n \n\nAD/T53/8 Second Stage Power Turbine Rotor Disc - Rework 1/86\n\nApplicability: T5313A, T5313A S/N Suffix \"A\", T5313B.\n\n \n\nDocument: 1. Lycoming Overhaul Modification Bulletin No. 0041, Rev. 3; or\n\n \n\n2. AD/LYC-T/9B.\n\n \n\nCompliance: Prior to installation in an aircraft following next reconditioning completed after 31 July 1973.\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":1671},"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This airworthiness directive remains tightly focused on its original technical purpose: mandating safety modifications to specific T53 engine rotor discs. The scope has not expanded beyond the original safety requirement for these particular engine models."},"complexity_factors":["Single-page document with no interpretation section","Only 3 specific engine models listed in applicability","Simple conditional trigger (reconditioning post-July 1973)","No nested exceptions or cross-references to other legislative provisions","Clear compliance action (follow specified technical bulletin)"],"plain_english_summary":"This safety rule requires a specific repair to certain Lycoming aircraft turbine engines (models T5313A and T5313B). \n\n**What it does:**\n- Mandates a rework (modification/repair) of the **second stage power turbine rotor disc** — a critical rotating component that helps power the engine.\n\n**Who it affects:**\n- Aircraft operators or maintenance organisations with these specific engine models.\n\n**When it applies:**\n- Before reinstalling the engine in an aircraft following its next overhaul or reconditioning (if that reconditioning was completed after 31 July 1973).\n\n**What must be done:**\n- The rework must follow specific technical guidelines in **Lycoming Overhaul Modification Bulletin No. 0041** (or comply with an earlier safety directive AD/LYC-T/9B).\n\n**Why it matters:**\n- This prevents dangerous failures of the turbine disc that could cause catastrophic engine failure during flight."}},"importantCases":[],"_links":{"self":"/api/acts/ad-t53-8-second-stage-power-turbine-rotor-disc-rework","history":"/api/acts/ad-t53-8-second-stage-power-turbine-rotor-disc-rework/history","analysis":"/api/acts/ad-t53-8-second-stage-power-turbine-rotor-disc-rework/analysis","conflicts":"/api/acts/ad-t53-8-second-stage-power-turbine-rotor-disc-rework/conflicts","importantCases":"/api/acts/ad-t53-8-second-stage-power-turbine-rotor-disc-rework/important-cases","documents":"/api/acts/ad-t53-8-second-stage-power-turbine-rotor-disc-rework/documents"}}