{"id":"F2006B10111","name":"AD/G164/6 - Carburettor Air Duct - Modification","slug":"ad-g164-6-carburettor-air-duct-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":55632,"registerId":"commonwealth-F2006B10111-current","compilationNumber":null,"startDate":"2026-04-02","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/G164/6 - Carburettor Air Duct - Modification","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 - 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n \n\n![](image.001.png)  Schweizer (Grumman) G-164 (Ag-Cat) Series Aeroplanes\n\n \n\nAD/G164/6 Carburettor Air Duct - Modification 9/66\n\nApplicability: All model G164A with S/Nos. 401 to 406, 408 to 417, 419 and 420. Document:  Grumman G164 SB No. 37.\n\nCompliance: Forthwith.\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\n \n\n \n","sortOrder":0}],"analysis":{"kimi_summary":{"_metrics":{"model":"kimi-k2.5","source":"moonshot-batch","completionTokens":2087},"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"The directive maintains its original narrow scope: mandating a specific airworthiness modification to the carburettor air ducts of identified Schweizer G-164A aircraft by serial number. There is no evidence of scope creep or expansion beyond this specific technical safety issue."},"complexity_factors":["Requires operators to obtain and follow an external technical document (Grumman Service Bulletin No. 37) not reproduced in the directive","Uses aviation industry abbreviations without definitions (S/Nos for serial numbers, SB for Service Bulletin)","Technical subject matter assumes familiarity with aircraft engine induction systems"],"plain_english_summary":"This is a mandatory safety order from the Civil Aviation Safety Authority (CASA) requiring an immediate fix to the **carburettor air duct** (the tube that feeds air into the engine's fuel system) on specific agricultural aircraft.\n\n**Who it affects:**\n- Owners and operators of **Schweizer (Grumman) G-164A Ag-Cat** aeroplanes with serial numbers 401–406, 408–417, 419, and 420\n\n**What you must do:**\n- Modify the carburettor air duct according to **Grumman Service Bulletin No. 37** (the manufacturer's official repair instructions)\n- Do this **immediately** (the legal term used is \"forthwith\")\n\n**Why it matters:**\nProblems with carburettor air ducts can cause engines to run poorly or fail completely. This directive ensures these specific aircraft receive a critical safety upgrade to prevent dangerous in-flight engine issues."}},"importantCases":[],"_links":{"self":"/api/acts/ad-g164-6-carburettor-air-duct-modification","history":"/api/acts/ad-g164-6-carburettor-air-duct-modification/history","analysis":"/api/acts/ad-g164-6-carburettor-air-duct-modification/analysis","conflicts":"/api/acts/ad-g164-6-carburettor-air-duct-modification/conflicts","importantCases":"/api/acts/ad-g164-6-carburettor-air-duct-modification/important-cases","documents":"/api/acts/ad-g164-6-carburettor-air-duct-modification/documents"}}