{"id":"F2008L02969","name":"AD/OH-58/5 - Main Rotor Trunnion","slug":"ad-oh-58-5-main-rotor-trunnion","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":74940,"registerId":"commonwealth-F2008L02969-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Bell OH-58A (206A-1) Series Helicopters","sectionType":"division","heading":"Bell OH-58A (206A-1) Series Helicopters","content":"### Bell OH-58A (206A-1) Series Helicopters\n\n| AD/OH-58/5 | Main Rotor Trunnion | 9/2008 |\n| ---------- | ------------------- | ------ |\n\n| Applicability: | Model OH-58A (Bell 206A-1) series helicopters, including all certificated versions; with main rotor trunnions part number 206-010-104-3, 206-011-113-001, or206-011-120-001, installed.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |\n| -------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | 1. For trunnions with less than 1,100 hours total time in service, accomplish a magnetic particle inspection in accordance with Bell Helicopter Alert Service Bulletin 206-80-7 Rev. A, or later FAA approved revision.2. For trunnions with more than 1,100 hours total time in service and less than 1,700 hours total time in service, accomplish a magnetic particle inspection in accordance with Bell Helicopter Alert Service Bulletin 206-80-7 Rev. A, or later FAA approved revision.3. For trunnions with 1,700 hours or more total time in service accomplish a magnetic particle inspection in accordance with Bell Helicopter Alert Service Bulletin 206-80-7 Rev. A, or later FAA approved revision.4. For trunnions with time unknown, accomplish a magnetic particle inspection in accordance with Bell Helicopter Alert Service Bulletin 206-80-7 Rev. A, or later FAA approved revision.If a crack is detected during any inspection, before further flight, replace the cracked trunnion with a serviceable trunnion.If no cracking is detected, reassemble and install the main rotor hub on the helicopter in accordance with the applicable Model 206 Maintenance and Overhaul Manual.Installation of trunnion part number 206-011-113-103 constitutes terminating action to the requirements of this Directive.Note: FAA AD 80-18-04 R1 Amdt 39-3954 refers. |\n| Compliance:    | 1. Before accumulating 1,200 hours and repeat before accumulating 2,400 hours, and thereafter at intervals not to exceed 600 hours.2. Within the next 100 hours time in service and repeat before accumulating 2,400 hours, and thereafter at intervals not to exceed 600 hours.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |\n\n|             | 3. Within the next 100 hours time in service, and thereafter at intervals not to exceed 600 hours.4. Within the next 100 hours time in service, and thereafter at intervals not to exceed 600 hours. |\n| ----------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n|             | This Airworthiness Directive becomes effective on 28 August 2008.                                                                                                                                    |\n| Background: | The FAA requires certain actions to prevent failure of the main rotor trunnion due to fatigue cracking.                                                                                              |\n\n![](image.001.png)  \nDavid Villiers  \nDelegate of the Civil Aviation Safety Authority\n\n14 July 2008","sortOrder":0},{"sectionNumber":"AD/OH-58/5","sectionType":"part","heading":"AD/OH-58/5","content":"## AD/OH-58/5","sortOrder":1},{"sectionNumber":"Main Rotor Trunnion","sectionType":"part","heading":"Main Rotor Trunnion","content":"## Main Rotor Trunnion","sortOrder":2},{"sectionNumber":"9/2008","sectionType":"part","heading":"9/2008","content":"## 9/2008","sortOrder":3}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The directive confines scope to Bell OH-58A (206A-1) helicopters with the listed trunnion part numbers (Applicability). It mirrors an FAA airworthiness requirement aimed at preventing trunnion fatigue failure (Background; Note referencing FAA AD). It does not expand applicability beyond those models/parts and provides a specific terminating action (installation of P/N 206-011-113-103) (Requirement)."},"complexity_factors":["Narrow applicability: limited to Model OH-58A (206A-1) helicopters with trunnion P/Ns 206-010-104-3, 206-011-113-001, or 206-011-120-001 (Applicability).","Multiple hour-based thresholds: different inspection triggers for <1,100 h, 1,100–1,699 h, ≥1,700 h and unknown time (Requirement).","Recurring compliance schedule tied to flight hours: inspections at specified TIS intervals and repeats every 600 hours after initial windows (Compliance) — increases recordkeeping and maintenance planning.","Immediate operational constraint on defect detection: any detected crack requires replacement before further flight (Requirement) — direct cost to operators for parts and downtime.","Dependence on an external document: inspections must follow Bell Alert Service Bulletin 206-80-7 Rev. A or later FAA-approved revision (Requirement) — introduces dependency on supplier/manufacturer and FAA approvals.","Terminative action specified: installation of trunnion P/N 206-011-113-103 ends the directive’s requirements (Requirement).","Low administrative discretion: directive sets mandatory actions and intervals, with no exception or alternative methods provided in the text (Requirement, Compliance).","Cross-reference to FAA AD creates regulatory linkage: Note references FAA AD 80-18-04 R1 Amdt 39-3954 and Background cites FAA requirement (Note, Background)."],"plain_english_summary":"Requires operators of Bell OH-58A (206A-1) helicopters fitted with specific main rotor trunnion part numbers to carry out repeated magnetic particle inspections and to replace any cracked trunnion before further flight. Inspections must follow Bell Helicopter Alert Service Bulletin 206-80-7 Rev. A (or a later FAA-approved revision) on hour-based schedules to reduce the risk of trunnion fatigue failure."},"kimi_summary":{"content_quality":"ok","complexity_score":4,"scope_assessment":{"changed":false,"description":"This AD maintains its original narrow scope — safety inspection of a specific helicopter part. It has not expanded beyond its initial purpose of preventing main rotor trunnion failures."},"complexity_factors":["Multiple conditional inspection schedules based on four distinct flight-hour thresholds (under 1,100 hrs; 1,100-1,700 hrs; over 1,700 hrs; unknown hours)","Cross-reference to external technical documents: Bell Helicopter Alert Service Bulletin 206-80-7 Rev. A and FAA AD 80-18-04 R1 Amdt 39-3954","Nested compliance timelines with repeating intervals (600-hour recurring inspections after initial deadlines)","Terminating action clause requiring specific replacement part number to end obligations","Immediate grounding requirement ('before further flight') if cracks detected"],"plain_english_summary":"This AD requires owners/operators of Bell OH-58A (Bell 206A-1) helicopters to perform magnetic-particle inspections of main rotor trunnions with certain part numbers, on a schedule tied to accumulated flight hours. Any crack found must be fixed with immediate part replacement and the helicopter is grounded until repaired. An upgraded trunnion part is accepted as a terminating action. \n\nIt prevents catastrophic rotor failure by catching fatigue cracks early and aligns Australian rules with the FAA."},"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"}},"importantCases":[],"_links":{"self":"/api/acts/ad-oh-58-5-main-rotor-trunnion","history":"/api/acts/ad-oh-58-5-main-rotor-trunnion/history","analysis":"/api/acts/ad-oh-58-5-main-rotor-trunnion/analysis","conflicts":"/api/acts/ad-oh-58-5-main-rotor-trunnion/conflicts","importantCases":"/api/acts/ad-oh-58-5-main-rotor-trunnion/important-cases","documents":"/api/acts/ad-oh-58-5-main-rotor-trunnion/documents"}}