{"id":"F2006B06355","name":"AD/PT6A/14 - Sungear Coupling Shaft Retaining Rings","slug":"ad-pt6a-14-sungear-coupling-shaft-retaining-rings","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":47578,"registerId":"commonwealth-F2006B06355-current","compilationNumber":null,"startDate":"2026-04-02","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/PT6A/14 - Sungear Coupling Shaft Retaining Rings","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)  Pratt and Whitney Canada Turbine Engines - PT6A Series\n\n \n\nAD/PT6A/14 Sungear Coupling Shaft Retaining Rings 10/85\n\nApplicability: All PT6A-6, -6A, -6B, -20, -27, -28 and -34 with S/Nos. as listed in the requirement document.\n\n \n\nDocument: 1. UACL SB No. 249;\n\n \n\n2.    UACL SB No. 1173, or\n\n \n\n3.    AD/UAC-T/12.\n\n \n\nCompliance:  Before installation in an aircraft following next reconditioning completed after 31 October 1972 or next time the affected area becomes accessible whichever occurs first.\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":3287},"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This directive maintains its original narrow technical scope addressing a specific mechanical safety issue with retaining rings in specific PT6A engine models. There is no evidence of scope creep or expansion beyond the original sungear coupling shaft issue."},"complexity_factors":["Extremely short text (under 150 words)","No definitions section or interpretive provisions","Simple conditional compliance trigger (whichever occurs first)","Relies entirely on external technical documents (service bulletins) for substantive requirements","Narrow, specific applicability limited to enumerated engine models"],"plain_english_summary":"**What this does:** This Airworthiness Directive (a legally binding aviation safety rule) mandates specific maintenance actions for certain Pratt & Whitney Canada PT6A aircraft engines. It requires compliance with technical service bulletins regarding **sungear coupling shaft retaining rings** — small mechanical components that secure parts on the engine's sun gear shaft.\n\n**Who it affects:** Owners and operators of aircraft with PT6A-6, -6A, -6B, -20, -27, -28, or -34 model engines, specifically those with serial numbers listed in the referenced technical documents.\n\n**What must be done:** Operators must follow the instructions in United Aircraft of Canada Limited (UACL) Service Bulletin No. 249, No. 1173, or Airworthiness Directive AD/UAC-T/12 (whichever applies to their specific engine).\n\n**When:** Before installing the engine in an aircraft following its next reconditioning (overhaul) after 31 October 1972, or the next time the affected area becomes accessible during maintenance — whichever happens first."}},"importantCases":[],"_links":{"self":"/api/acts/ad-pt6a-14-sungear-coupling-shaft-retaining-rings","history":"/api/acts/ad-pt6a-14-sungear-coupling-shaft-retaining-rings/history","analysis":"/api/acts/ad-pt6a-14-sungear-coupling-shaft-retaining-rings/analysis","conflicts":"/api/acts/ad-pt6a-14-sungear-coupling-shaft-retaining-rings/conflicts","importantCases":"/api/acts/ad-pt6a-14-sungear-coupling-shaft-retaining-rings/important-cases","documents":"/api/acts/ad-pt6a-14-sungear-coupling-shaft-retaining-rings/documents"}}