{"id":"F2006B06362","name":"AD/PT6A/23 - Replacement of Compressor Delivery Heated Air Tube by a Non-Metallic Hose","slug":"ad-pt6a-23-replacement-of-compressor-delivery-heated-air-tube-by-a-non-metallic-hose","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":47601,"registerId":"commonwealth-F2006B06362-current","compilationNumber":null,"startDate":"2026-04-02","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/PT6A/23 - Replacement of Compressor Delivery Heated Air Tube by a Non-Metallic Hose","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/23 Replacement of Compressor Delivery Heated\n\nAir Tube by a Non-Metallic Hose\n\n\n10/85\n\n \n\nApplicability: PT6A-11AG engines with S/Nos. prior to PC-E10139. PT6A-15AG engines with S/Nos. prior to PC-E14012.\n\n \n\nDocument: 1. Pratt & Whitney Aircraft of Canada Ltd. SB No. 12024 R1, or\n\n \n\n2. AD/UAC-T/38.\n\n \n\nCompliance: At first opportunity consistent with availability of parts but not later than next HSI or next overhaul whichever is sooner.\n\n \n\nBackground: Overseas, failures of the rigid compressor delivery heated air tubes have occurred.\n\nThis Directive is issued in order to preclude further failures.\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":1419},"content_quality":"ok","complexity_score":1,"scope_assessment":{"changed":false,"description":"The directive remains strictly limited to its original purpose of replacing specific compressor air tubes on the designated engine models to address known failures."},"complexity_factors":["Single-page directive with no defined terms or legislative cross-references","Limited applicability to only two specific engine models by serial number range","Single, unambiguous mechanical task (part replacement)","Simple compliance deadline without nested exceptions or conditional logic"],"plain_english_summary":"This Airworthiness Directive is a mandatory safety order requiring owners and operators of specific Pratt & Whitney Canada PT6A turbine engines to replace a faulty part.\n\n**What it requires:**\nYou must swap out the rigid metal **compressor delivery heated air tube** (a component that carries hot compressed air within the engine) and replace it with a flexible non-metallic hose.\n\n**Who it affects:**\n- PT6A-11AG engines with serial numbers before PC-E10139\n- PT6A-15AG engines with serial numbers before PC-E14012\n\n**Why it matters:**\nThe original rigid tubes have been failing in other countries, creating potential safety hazards. This directive prevents engine damage or failure by switching to a more durable hose design.\n\n**When you must comply:**\nMake the replacement at the first opportunity when parts are available, but no later than your next **Hot Section Inspection** (a major engine check) or engine overhaul — whichever happens first."}},"importantCases":[],"_links":{"self":"/api/acts/ad-pt6a-23-replacement-of-compressor-delivery-heated-air-tube-by-a-non-metallic-hose","history":"/api/acts/ad-pt6a-23-replacement-of-compressor-delivery-heated-air-tube-by-a-non-metallic-hose/history","analysis":"/api/acts/ad-pt6a-23-replacement-of-compressor-delivery-heated-air-tube-by-a-non-metallic-hose/analysis","conflicts":"/api/acts/ad-pt6a-23-replacement-of-compressor-delivery-heated-air-tube-by-a-non-metallic-hose/conflicts","importantCases":"/api/acts/ad-pt6a-23-replacement-of-compressor-delivery-heated-air-tube-by-a-non-metallic-hose/important-cases","documents":"/api/acts/ad-pt6a-23-replacement-of-compressor-delivery-heated-air-tube-by-a-non-metallic-hose/documents"}}