{"id":"F2006B11072","name":"AD/LA-4/21 - Auxiliary Fuel Tank Lines - Inspection and Replacement, Modification","slug":"ad-la-4-21-auxiliary-fuel-tank-lines-inspection-and-replacement-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":56707,"registerId":"commonwealth-F2006B11072-current","compilationNumber":null,"startDate":"2026-04-02","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/LA-4/21 - Auxiliary Fuel Tank Lines - Inspection and Replacement, 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)  Consolidated Aeronautics, Colonial and LA-4 Series Aeroplanes\n\n \n\nAD/LA-4/21 Auxiliary Fuel Tank Lines - Inspection\n\nand Replacement, Modification\n\n\n2/84\n\n \n\nApplicability: All models LA-4 and LA-4-200 up to S/No. 1091 and Model LA-4-250 with S/Nos 2 and 3 fitted with AEROFAB 180004 Auxiliary Fuel system to supplemental type certificate SA B76EA.\n\n \n\nDocument: Lake Aircraft Division Consolidated Aeronautics SB No. B-65. Compliance: Within 100 hours time in service after 30 April 1984.\n\nBackground: The manufacturer has advised that there is a possibility of chafing of the fuel line from the auxiliary fuel tank pump to the main fuel tank.\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":1874},"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This directive maintains its original narrow scope addressing a specific mechanical defect (fuel line chafing) in defined aircraft models. There is no evidence of scope creep or expansion beyond the original safety issue identified in the manufacturer's service bulletin."},"complexity_factors":["Single operative requirement with no exceptions or sub-clauses","Narrow applicability limited to specific aircraft serial numbers and equipment configuration","Clear compliance metric (100 hours time in service)","Only one external reference (manufacturer Service Bulletin B-65)","No defined terms section or interpretive provisions"],"plain_english_summary":"Mandatory Airworthiness Directive requires owners of Lake LA-4 and LA-4-200 (serials ≤1091) and LA-4-250 (S/N 2–3) aircraft fitted with the AEROFAB 180004 auxiliary fuel system to inspect and, if necessary, replace or modify the fuel line from the auxiliary pump to the main tank per Service Bulletin B-65 within 100 flight hours after 30 April 1984.\n\nIt addresses chafing that can cause fuel leaks, risking engine failure or fire."}},"importantCases":[],"_links":{"self":"/api/acts/ad-la-4-21-auxiliary-fuel-tank-lines-inspection-and-replacement-modification","history":"/api/acts/ad-la-4-21-auxiliary-fuel-tank-lines-inspection-and-replacement-modification/history","analysis":"/api/acts/ad-la-4-21-auxiliary-fuel-tank-lines-inspection-and-replacement-modification/analysis","conflicts":"/api/acts/ad-la-4-21-auxiliary-fuel-tank-lines-inspection-and-replacement-modification/conflicts","importantCases":"/api/acts/ad-la-4-21-auxiliary-fuel-tank-lines-inspection-and-replacement-modification/important-cases","documents":"/api/acts/ad-la-4-21-auxiliary-fuel-tank-lines-inspection-and-replacement-modification/documents"}}