{"id":"F2006B02035","name":"AD/AA-1/4 - Fuel Tank Contents Manometer Vent Lines - Modification","slug":"ad-aa-1-4-fuel-tank-contents-manometer-vent-lines-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":41257,"registerId":"commonwealth-F2006B02035-current","compilationNumber":null,"startDate":"2026-04-01","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/AA-1/4 - Fuel Tank Contents Manometer Vent Lines - Modification","content":"---\nmeta-content-style-type: text/css\nmeta-content-type: application/xhtml+xml; charset=utf-8\nmeta-description: CASA Airworthiness Directive\nmeta-generator: Aspose.Words for .NET 22.10.0\nmeta-keywords: Issue NK,Aircraft below 5700 kg,Gulfstream (Grumman American/ American Aviation) AA-1 Series Aeroplanes,Fuel Tank Contents Manometer Vent Lines - Modification,4\ntitle: Airworthiness Directive - AD/AA-1/4 - Fuel Tank Contents Manometer Vent Lines - Modification\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)  Gulfstream (Grumman American/ American Aviation) AA-1 Series Aeroplanes\n\n \n\nAD/AA-1/4 Fuel Tank Contents Manometer NK\n\nVent Lines - Modification\n\n \n\nApplicability: Model AA-1A.\n\n \n\nRequirement: Inspect each fuel tank contents manometer vent line P/N 401131-3 and ensure that the plastic vent line is not kinked or likely to kink in service.\n\n \n\nCompliance: Before issue of a Certificate of Airworthiness.\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":1563},"content_quality":"ok","complexity_score":1,"scope_assessment":{"changed":false,"description":"This directive maintains a narrow, targeted scope addressing a specific mechanical defect (kinked plastic vent lines) on a single aircraft model. There is no evidence of scope creep or expansion beyond the original airworthiness safety concern."},"complexity_factors":["Extremely brief text (approximately 50 words of operative provisions)","Single applicability criterion (Model AA-1A only)","One straightforward inspection task with no alternative methods or exceptions","No defined terms, cross-references, or conditional logic","Simple temporal trigger (before Certificate of Airworthiness issuance)"],"plain_english_summary":"**What this does:** This is a safety rule for owners and operators of **Gulfstream AA-1A light aircraft** (small planes under 5,700 kg).\n\n**The requirement:** Before an aircraft can receive its **Certificate of Airworthiness** (the official document certifying a plane is safe to fly), the fuel tank vent line (part number 401131-3) must be physically inspected. The inspector must verify that the plastic vent tube is **not kinked** (sharply bent or pinched) and is not likely to kink during normal operation.\n\n**Why it matters:** A kinked fuel vent line can block airflow to the fuel tank, potentially causing incorrect fuel readings, fuel starvation, or engine failure. This one-time check prevents a known safety hazard before the aircraft enters service."}},"importantCases":[],"_links":{"self":"/api/acts/ad-aa-1-4-fuel-tank-contents-manometer-vent-lines-modification","history":"/api/acts/ad-aa-1-4-fuel-tank-contents-manometer-vent-lines-modification/history","analysis":"/api/acts/ad-aa-1-4-fuel-tank-contents-manometer-vent-lines-modification/analysis","conflicts":"/api/acts/ad-aa-1-4-fuel-tank-contents-manometer-vent-lines-modification/conflicts","importantCases":"/api/acts/ad-aa-1-4-fuel-tank-contents-manometer-vent-lines-modification/important-cases","documents":"/api/acts/ad-aa-1-4-fuel-tank-contents-manometer-vent-lines-modification/documents"}}