{"id":"F2006B08730","name":"AD/DAUPHIN/2 - Tail Fin Ballast Weight - Installation","slug":"ad-dauphin-2-tail-fin-ballast-weight-installation","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":51961,"registerId":"commonwealth-F2006B08730-current","compilationNumber":null,"startDate":"2026-04-02","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/DAUPHIN/2 - Tail Fin Ballast Weight - Installation","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)  Eurocopter SA 360 and SA 365 (Dauphin) Series Helicopters\n\n \n\nAD/DAUPHIN/2 Tail Fin Ballast Weight - Installation 9/79\n\nApplicability: All models SA 365C and 365C1 fitted with skid type landing gear. Document:  Dauphin SB No. 53.04.\n\nCompliance: Before certification.\n\n \n\nBackground:  Addition of ballast weight is required to reduce vibration levels in the tail boom rear section.\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":2243},"content_quality":"ok","complexity_score":1,"scope_assessment":{"changed":false,"description":"The directive maintains its original narrow scope targeting specific Dauphin helicopter variants for a specific vibration-reduction safety modification."},"complexity_factors":["Single-page directive with no subsections or defined terms section","Single unconditional requirement (install ballast weight before certification)","Straightforward applicability limited to two specific aircraft model numbers","No cross-references to other legislative provisions or conditional exceptions"],"plain_english_summary":"**What it is:** This is a safety directive (called an Airworthiness Directive) issued by the Civil Aviation Safety Authority (CASA) under aviation safety law.\n\n**What it requires:** Owners and operators of specific Eurocopter Dauphin helicopters (models SA 365C and 365C1 with skid-type landing gear) must install ballast weights on the tail fin.\n\n**Why:** To reduce dangerous vibration levels in the rear section of the tail boom that could affect aircraft structural integrity and safety.\n\n**When:** This modification must be completed before the aircraft is certified as airworthy (before certification).\n\n**Key details:**\n- **Applies to:** SA 365C and 365C1 models fitted with skid landing gear only\n- **Technical standard:** Follow the instructions in Dauphin Service Bulletin No. 53.04\n- **First issued:** September 1979"}},"importantCases":[],"_links":{"self":"/api/acts/ad-dauphin-2-tail-fin-ballast-weight-installation","history":"/api/acts/ad-dauphin-2-tail-fin-ballast-weight-installation/history","analysis":"/api/acts/ad-dauphin-2-tail-fin-ballast-weight-installation/analysis","conflicts":"/api/acts/ad-dauphin-2-tail-fin-ballast-weight-installation/conflicts","importantCases":"/api/acts/ad-dauphin-2-tail-fin-ballast-weight-installation/important-cases","documents":"/api/acts/ad-dauphin-2-tail-fin-ballast-weight-installation/documents"}}