{"id":"F2006B09329","name":"AD/ECUREUIL/11 Amdt 2 - Main Gear Box - Spectrometric Analysis of Lubricating Oil","slug":"ad-ecureuil-11-amdt-2-main-gear-box-spectrometric-analysis-of-lubricating-oil","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":53498,"registerId":"commonwealth-F2006B09329-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/ECUREUIL/11 Amdt 2 - Main Gear Box - Spectrometric Analysis of Lubricating Oil","content":"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n![](image.001.png)  \nEurocopter AS 350 (Ecureuil) Series Helicopters\n\nAD/ECUREUIL/11\n\nAmdt 2\n\n  \n\nMain Gear Box \\- Spectrometric Analysis of Lubricating Oil\n\n  \n10/88\n\nApplicability: All model AS 350 helicopters fitted with bevel reduction gear modules P/N 350 A32- 0300-00 or 01.\n\nNote: Reduction gear module P/N 350A32-0300-02 with vertical shaft modified to AMS 07-7027 or modules P/N 350 A32-0300-00 or 01 modified to either AMS 07- 7042 or AMS 07-7027 are exempt from the requirement of this Directive.\n\nRequirement: Action in accordance with SB No 05.06 Revision 2\\. Compliance: As detailed in the requirement document.\n\nBackground: This AD supersedes AD/ECUREUIL/9, which is CANCELLED. The manufacturer considers that the wear check to the bevel gear module shaft splines called up in Telex Service 05-05 (AD/ECUREUIL/9) was inaccurate, and has introduced a spectrometric monitoring programme for the main gearbox oil. The manufacturer has further advised that modified bevel gear reduction modules do not require inspection. Amendment 2 to this Directive details those modules.","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This amendment remains tightly scoped to its original purpose: monitoring wear in specific bevel gear modules. Amendment 2 simply refines the exemption list based on manufacturer data about which modified parts no longer require monitoring. The scope has not expanded beyond the specific mechanical issue it was designed to address."},"complexity_factors":["Single, specific technical requirement (oil spectrometric analysis)","Clear applicability clause with explicit part numbers","Single exemption note with specific modification standards referenced","No nested conditional logic or cross-references to other legislation","Short document (approximately 150 words)","Only 3 defined technical terms (part numbers and service bulletin reference)"],"plain_english_summary":"This AD mandates regular spectrometric analysis of main gearbox lubricating oil on Eurocopter AS350 (Ecureuil) helicopters to detect early bevel reduction-gear wear, replacing a prior, unreliable spline inspection. It applies to owners, operators and maintenance organisations for affected gear part numbers, but exempts gear modules upgraded to newer specifications. The change aims to prevent catastrophic gearbox failure by catching internal wear sooner."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"The directive supersedes the prior AD that required a bevel gear spline-wear check and instead mandates spectrometric monitoring of gearbox oil per SB No. 05.06 Rev 2. It narrows affected actions to oil analysis and exempts specific modified reduction modules (P/N 350A32-0300-02 and 00/01 modified to AMS 07-7042 or AMS 07-7027), shifting ongoing compliance costs and procedures onto operators of non-exempt modules."},"complexity_factors":["Technical monitoring requirement: spectrometric oil analysis (requires laboratory capability or contracted service and sample handling procedures)","Precise applicability by part number (P/N 350A32-0300-00/01) and explicit exemptions for modified modules","Normative reference to an external compliance document (Service Bulletin No. 05.06 Revision 2) that prescribes the detailed procedure","Operational impact on maintenance programmes (sampling frequency, record-keeping, and potential follow-up actions)","Transition from a prior inspection method (spline-wear check) to ongoing oil monitoring, changing logistics and possible training needs"],"plain_english_summary":"This airworthiness directive requires operators of AS350 (Ecureuil) helicopters fitted with bevel reduction gear modules P/N 350A32-0300-00 or 01 to carry out spectrometric analysis of main gearbox lubricating oil in accordance with Service Bulletin No. 05.06 Revision 2. The Civil Aviation Safety Authority mandates compliance and operators pay for sampling, analysis and any follow-up. The measure replaces a prior spline-wear inspection; certain modified modules (P/N 350A32-0300-02 or 00/01 modified to AMS 07-7042 or AMS 07-7027) are exempt."}},"importantCases":[],"_links":{"self":"/api/acts/ad-ecureuil-11-amdt-2-main-gear-box-spectrometric-analysis-of-lubricating-oil","history":"/api/acts/ad-ecureuil-11-amdt-2-main-gear-box-spectrometric-analysis-of-lubricating-oil/history","analysis":"/api/acts/ad-ecureuil-11-amdt-2-main-gear-box-spectrometric-analysis-of-lubricating-oil/analysis","conflicts":"/api/acts/ad-ecureuil-11-amdt-2-main-gear-box-spectrometric-analysis-of-lubricating-oil/conflicts","importantCases":"/api/acts/ad-ecureuil-11-amdt-2-main-gear-box-spectrometric-analysis-of-lubricating-oil/important-cases","documents":"/api/acts/ad-ecureuil-11-amdt-2-main-gear-box-spectrometric-analysis-of-lubricating-oil/documents"}}