{"id":"F2009L02855","name":"AD/AS 355/18 Amdt 1 - Main Rotor Sleeve Beams","slug":"ad-as-355-18-amdt-1-main-rotor-sleeve-beams","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":80182,"registerId":"commonwealth-F2009L02855-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Eurocopter AS 355 (Twin Ecureuil) Series","sectionType":"division","heading":"Eurocopter AS 355 (Twin Ecureuil) Series Helicopters","content":"### Eurocopter AS 355 (Twin Ecureuil) Series Helicopters\n\n| AD/AS 355/18 Amdt 1 | Main Rotor Sleeve Beams | 8/2009 |\n| ------------------- | ----------------------- | ------ |\n\n| Applicability: | All model AS 355 helicopters with main rotor head roving sleeve, upper and lower beams part numbers 350A31.1831.04, .05, .06 and .07.                                                                                                                                                                                                             |\n| -------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | Remove main rotor blades and visually check that sleeve bushes are not separated. If any bush separation is found, remove and replace the sleeve beams concerned. Requirement document is French AD 86-35-28 (B), paragraph B; or USA AD86-19-15, paragraph C.Note: Aerospatiale Telex Service Bulletin No. 01.12 refers (no longer distributed.) |\n| Compliance:    | Before further flight in the event of a sudden or repeated occurrence of a severe tracking defect.Compliance with the original issue of this Directive constitutes compliance with this Amendment.                                                                                                                                                |\n|                | This Amendment becomes effective on 30 July 2009.                                                                                                                                                                                                                                                                                                 |\n| Background:    | The manufacturer reports cracking in the blade attachment area of the main rotor sleeve beams of a Dauphin SA 365C helicopter. The original issue of this Airworthiness Directive became effective in May 1986.                                                                                                                                   |\n|                | This Amendment is issued to add Part Nos to Applicability; reduce reliance on Service Bulletin No. 01.12 which is no longer distributed; and to identify French and USA Airworthiness Directives.                                                                                                                                                 |\n\n![](image.001.png)  \nDavid Villiers  \nDelegate of the Civil Aviation Safety Authority\n\n18 June 2009","sortOrder":0},{"sectionNumber":"AD/AS 355/18 Amdt 1","sectionType":"part","heading":"AD/AS 355/18 Amdt 1","content":"## AD/AS 355/18 Amdt 1","sortOrder":1},{"sectionNumber":"Main Rotor Sleeve Beams","sectionType":"part","heading":"Main Rotor Sleeve Beams","content":"## Main Rotor Sleeve Beams","sortOrder":2},{"sectionNumber":"8/2009","sectionType":"part","heading":"8/2009","content":"## 8/2009","sortOrder":3}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"The amendment modifies scope by adding specific sleeve beam part numbers to the Applicability field, reducing reliance on Aerospatiale Telex Service Bulletin No. 01.12 (not distributed), and explicitly identifying the related French and U.S. airworthiness directives. It does not alter the core inspection-and-replace requirement, but clarifies which parts and external documents govern compliance (see 'Applicability', 'Requirement', 'Background')."},"complexity_factors":["Technical inspection requirement: removal of main rotor blades and visual check for sleeve bush separation (Requirement).","Clear compliance trigger: action required 'before further flight' but only 'in the event of a sudden or repeated occurrence of a severe tracking defect' — requires judgement about what constitutes that defect (Compliance).","Narrow applicability defined by specific part numbers 350A31.1831.04, .05, .06 and .07 — operators must identify fitted parts (Applicability).","Replacement obligation if separation found creates logistical and cost implications for sourcing and installing sleeve beams (Requirement).","Cross-references to external documents: French AD 86-35-28(B) and USA AD86-19-15 are cited, and reliance on Service Bulletin No. 01.12 is reduced because it is no longer distributed, which affects where operators obtain compliance detail (Requirement / Background).","Continuity with historical directive: original AD from May 1986 remains relevant and compliance with the original issue constitutes compliance with this amendment, creating potential overlap to resolve (Background).","Fixed effective date and statement about the amendment’s relation to the original directive affect timing and retrospective compliance assessment (Compliance)."],"plain_english_summary":"This directive requires operators of Eurocopter AS 355 helicopters fitted with specified main rotor sleeve beam part numbers to remove the main rotor blades and visually inspect the sleeve bushes; if any bush separation is found the sleeve beams must be removed and replaced. Compliance is required before further flight after a sudden or repeated severe tracking defect.\n\nThe amendment adds specific part numbers to applicability, stops relying on a no-longer-distributed service bulletin, and cross-references related French and U.S. airworthiness directives."},"flash_summary_failed":{"failed":true,"reason":"Unauthenticated. Configure AI_GATEWAY_API_KEY or use a provider module. Learn more: https://ai-sdk.dev/unauthenticated-ai-gateway","source":"analysis-cron"},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":true,"description":"The original 1986 directive addressed a specific safety issue with main rotor sleeve beams. This 2009 amendment has expanded the scope by adding additional part numbers to the applicability list (the .04, .05, .06, and .07 variants), effectively covering more helicopters than the original. It also shifts reliance from a manufacturer's service bulletin (now obsolete) to foreign airworthiness directives, changing the technical reference framework while maintaining the same safety intent."},"complexity_factors":["Single, specific mechanical inspection requirement with clear trigger condition","Only 4 specific part numbers listed in applicability","One main compliance pathway with straightforward exception (prior compliance accepted)","Minimal cross-referencing: references two foreign airworthiness directives and one obsolete service bulletin","No nested definitions or conditional sub-clauses","Document is approximately 250 words excluding formatting artifacts"],"plain_english_summary":"This AD requires operators of Eurocopter AS 355 helicopters with certain main rotor sleeve beams to inspect the sleeve bushes for separation whenever a sudden or repeated severe rotor-tracking problem occurs, and to remove blades for visual inspection before further flight. Damaged beams must be replaced. It prevents catastrophic rotor failure; the 2009 amendment expands affected part numbers and updates references. Previous compliance with the 1986 directive remains valid."}},"importantCases":[],"_links":{"self":"/api/acts/ad-as-355-18-amdt-1-main-rotor-sleeve-beams","history":"/api/acts/ad-as-355-18-amdt-1-main-rotor-sleeve-beams/history","analysis":"/api/acts/ad-as-355-18-amdt-1-main-rotor-sleeve-beams/analysis","conflicts":"/api/acts/ad-as-355-18-amdt-1-main-rotor-sleeve-beams/conflicts","importantCases":"/api/acts/ad-as-355-18-amdt-1-main-rotor-sleeve-beams/important-cases","documents":"/api/acts/ad-as-355-18-amdt-1-main-rotor-sleeve-beams/documents"}}