{"id":"F2006B09397","name":"AD/ECUREUIL/96 - Rear Structure Junction Frame","slug":"ad-ecureuil-96-rear-structure-junction-frame","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":53738,"registerId":"commonwealth-F2006B09397-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"AIRWORTHINESS DIRECTIVE","sectionType":"part","heading":"AIRWORTHINESS DIRECTIVE","content":"# AIRWORTHINESS DIRECTIVE\n\n![](image.001.png)  \n\nFor the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (AD) under subregulation 39.1 (1) of CASR 1998. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.\n\n![](image.001.png)  \n\nEurocopter AS 350 (Ecureuil) Series Helicopters","sortOrder":0},{"sectionNumber":"AD/ECUREUIL/96 Rear Structure Junction F","sectionType":"part","heading":"AD/ECUREUIL/96 Rear Structure Junction Frame 5/2004","content":"# AD/ECUREUIL/96 Rear Structure Junction Frame 5/2004\n\nApplicability: Model AS 350 B, BA, BB, B1, B2, B3, and D helicopters:\n\n    \\- pre-Mod 073215, or\n\n    \\- not equipped with the four reinforcement angles, part numbers 350A08.2493.20 /\n\n.21 / .22 / .23, following the repair carried out in accordance with MRM Work Card 53.10.22.772.\n\nRequirement: Action in accordance with Eurocopter Alert Service Bulletin No. 05.00.43 original issue, or Revision 1.\n\nNote: DGAC AD F-2004-035 refers.\n\nCompliance: As specified in the Requirement document, with the effective date of this Directive substituted for receipt date of the Requirement document.\n\nThis Airworthiness Directive becomes effective on 13 May 2004.\n\nBackground: Reports were received by the manufacturer of cracks in the rear structure / tail boom junction frame during unscheduled inspections. In some cases, the crack lengths were significant and were not visible externally on the tail boom skin. Undetected cracking combined with a high thrust load from the tail rotor, may result in failure due to insufficient strength margins of the junction frame.\n\n![Signature of David Villiers, Delegate of the Civil Aviation Safety Authority.](image.002.png)  \n\nDavid Villiers\n\nDelegate of the Civil Aviation Safety Authority 2 April 2004\n\n![](image.001.png)","sortOrder":1}],"analysis":{"flash_summary_failed":{"failed":true,"reason":"A positive credit balance is required for all requests, including BYOK, so fallback providers remain available. Add credits at https://vercel.com/d?to=%2F%5Bteam%5D%2F%7E%2Fai%3Fmodal%3Dtop-up to continue.","source":"analysis-cron"},"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":false,"description":"The Directive applies narrowly to specified AS350 model helicopters lacking a particular mod or reinforcement parts and mandates action per the referenced Eurocopter service bulletin. The text shows no expansion or narrowing beyond that stated applicability; it implements a targeted corrective inspection/repair regime as described."},"complexity_factors":["Dependency on external technical documents: Eurocopter Alert Service Bulletin No. 05.00.43 is the operative instruction (Requirement).","Conditional applicability based on modification status (pre‑Mod 073215) or absence of specific reinforcement angles (part numbers 350A08.2493.20/.21/.22/.23) after a repair (Applicability).","Reference to a specific repair procedure (MRM Work Card 53.10.22.772) creates procedural linkage to other maintenance records and practices (Applicability).","Compliance timing is tied to the Directive's effective date substituted for the ASB receipt date, affecting scheduling and recordkeeping (Compliance).","Technical inspection complexity: cracks may be internal and not visible externally, requiring intrusive inspection techniques and possible repair (Background).","Cross-reference to an overseas airworthiness directive (DGAC AD F-2004-035) may require operators to consult additional regulator guidance (Note)."],"plain_english_summary":"This Airworthiness Directive requires operators of certain Eurocopter AS350 B/BA/BB/B1/B2/B3 and D helicopters that are pre‑Mod 073215, or that lack four specified reinforcement angles after a prior repair, to perform inspections and any necessary repairs to the rear‑structure / tail‑boom junction frame in accordance with Eurocopter Alert Service Bulletin No. 05.00.43 (original or Rev 1). Aircraft owners/operators must pay for and carry out the work; the CASA delegate enforces compliance and set the effective date (13 May 2004). The action addresses hidden cracking that can lead to structural failure under tail‑rotor loads."},"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This is a standard airworthiness directive addressing a specific safety-critical structural defect. It remains tightly focused on its original purpose: mandating inspection and repair of the rear structure junction frame on affected helicopter models. No scope creep is evident."},"complexity_factors":["Short, single-purpose directive with one specific mechanical issue","Only 7 defined model variants in applicability section","Single cross-reference to manufacturer service bulletin (Eurocopter Alert Service Bulletin No. 05.00.43)","One conditional applicability criterion (pre-modification status or absence of specific part numbers)","No nested exceptions or complex conditional logic","Incorporates external technical document by reference rather than reproducing instructions"],"plain_english_summary":"This CASA safety order requires owners/operators of certain Eurocopter AS350 helicopters (B/BA/BB/B1/B2/B3/D) that haven’t had reinforced parts fitted to inspect and repair the tail‑boom junction frame where cracks were found.  \n\nThe work must follow Eurocopter Alert Service Bulletin No. 05.00.43 by the compliance times set in that bulletin (counting from 13 May 2004) because undetected cracks could cause tail failure and loss of control."}},"importantCases":[],"_links":{"self":"/api/acts/ad-ecureuil-96-rear-structure-junction-frame","history":"/api/acts/ad-ecureuil-96-rear-structure-junction-frame/history","analysis":"/api/acts/ad-ecureuil-96-rear-structure-junction-frame/analysis","conflicts":"/api/acts/ad-ecureuil-96-rear-structure-junction-frame/conflicts","importantCases":"/api/acts/ad-ecureuil-96-rear-structure-junction-frame/important-cases","documents":"/api/acts/ad-ecureuil-96-rear-structure-junction-frame/documents"}}