{"id":"F2006B04387","name":"AD/BELL 205/51 Amdt 1 - Vertical Fin Spar Cap","slug":"ad-bell-205-51-amdt-1-vertical-fin-spar-cap","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":44212,"registerId":"commonwealth-F2006B04387-current","compilationNumber":null,"startDate":"2026-04-02","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/BELL 205/51 Amdt 1 - Vertical Fin Spar Cap","content":"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\nBell Helicopter Textron 205 Series Helicopters\n\nAD/BELL 205/51\n\nAmdt 1\n\n  \nVertical Fin Spar Cap 3/88\n\nApplicability: 212-030-447-001/-101. This will include S/No 30229 to 30332, as well as any earlier S/No helicopters which have had this P/No spar cap assembly installed subsequent to delivery.\n\nRequirement: 1. Inspect in accordance with Part I of Bell Alert Service Bulletin No 205-86-23, original issue dated 26 June 1986. Revision A may not be used, notwithstanding the general provisions of paragraph 3.3 of ANO 105.\n\n2. Repair discrepant spar cap assemblies in accordance with Part II of Bell Alert Service Bulletin No. 205-86-23 (any issue).\n\nCompliance: For Requirement 1: Within 20 hours time in service after 24 March 1988, but not later than 24 April 1988.\n\nFor Requirement 2: Within the next 200 hours time in service after 24 March 1988, but not later than 24 September 1988.\n\nBackground: Some spar cap assemblies P/No 212-030-447-001/-101 were milled outside tolerances, causing a reduction in the thickness of the spar cap. Fatigue cracking has been a problem even with conforming spar assemblies on similar models (212, 412), and any reduction in cap thickness will only increase the risk. This Amendment increases the serial number range for affected helicopters in line with Revision A to the ASB, but retains the 0.190 inch cap thickness lower limit of the original issue. A fatigue substantiation for the 0.155 inch limit contained in Rev A has not yet been received.","sortOrder":0}],"analysis":{"kimi_summary":{"_metrics":{"model":"kimi-k2.5","source":"moonshot-batch","completionTokens":1941},"content_quality":"ok","complexity_score":4,"scope_assessment":{"changed":true,"description":"This amendment expands the applicability of the original directive to cover additional helicopter serial numbers (30229-30332) in line with the manufacturer's updated service bulletin data, while paradoxically retaining the original inspection standard (0.190 inch minimum thickness) rather than adopting the revised 0.155 inch standard from Revision A of the service bulletin."},"complexity_factors":["Extensive use of aviation-specific part and serial numbers requiring cross-referencing","Dual-track compliance deadlines based on flight hours versus fixed calendar dates (whichever comes first)","Specific exception to general rule regarding use of revised service bulletins (override of ANO 105 para 3.3)","Reference to external technical document (Bell Alert Service Bulletin) without reproducing its contents"],"plain_english_summary":"This AD requires urgent inspection and, if needed, repair of the vertical fin spar cap on Bell 205 helicopters that have part number 212-030-447-001 or -101 installed (serials 30229–30332 and earlier airframes retrofitted).  \n\nIt enforces the original Bell Alert Service Bulletin 205-86-23 criteria (minimum spar cap thickness 0.190\") despite a later revision, with short flight-hour compliance windows to prevent spar-cap fatigue cracking and possible fin structural failure."}},"importantCases":[],"_links":{"self":"/api/acts/ad-bell-205-51-amdt-1-vertical-fin-spar-cap","history":"/api/acts/ad-bell-205-51-amdt-1-vertical-fin-spar-cap/history","analysis":"/api/acts/ad-bell-205-51-amdt-1-vertical-fin-spar-cap/analysis","conflicts":"/api/acts/ad-bell-205-51-amdt-1-vertical-fin-spar-cap/conflicts","importantCases":"/api/acts/ad-bell-205-51-amdt-1-vertical-fin-spar-cap/important-cases","documents":"/api/acts/ad-bell-205-51-amdt-1-vertical-fin-spar-cap/documents"}}