{"id":"F2006B04442","name":"AD/BELL 206/128 - Main Rotor Blade and Trim Tab","slug":"ad-bell-206-128-main-rotor-blade-and-trim-tab","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":44279,"registerId":"commonwealth-F2006B04442-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/BELL 206/128 - Main Rotor Blade and Trim Tab","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)  \nBell Helicopter Textron Canada (BHTC) 206 and Agusta Bell 206 Series Helicopters\n\nAD/BELL 206/128 Main Rotor Blade and Trim Tab 2/95\n\nApplicability: All Bell 206A, 206B, 206L, 206L-1, 206L-3 and 206L-4 helicopters equipped with main rotor blade P/N 206-015-001-107 or P/N 206-010-200-133 and having a serial number beginning with prefix “A”. Those blades P/N 206-010-200-133 or P/N 206- 015-001-107 with “A” prefixed serial numbers listed in Bell Alert Service Bulletins 206-93-77 or 206L-93-92 are not affected by this AD.\n\nRequirement: 1. Visually inspect, for cracking, the inboard trim tab and the upper and lower surfaces of the main rotor blade in the area of the inboard trim tab.\n\nInspect using a 10X magnifying glass and polish out any grinding or sanding marks in accordance with Part I of the applicable Bell Alert Service Bulletins.\n\n2. Blades with cracks in the inboard trim tab may be returned to service after reworking in accordance with Part II of the applicable Bell Alert Service Bulletins. Blades with cracks at other locations shall be removed from service.\n\nNote: FAA AD 94-15-07 refers.\n\nCompliance: Inspect and rework as required within 50 hours time in service from 2 February 1995.\n\nBackground: A number of cracks have been reported in the main rotor blade trailing edge near the inboard trim tab. Timely inspection will prevent failure of the rotor blade and loss of the helicopter.","sortOrder":0}],"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"},"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This is a discrete, time-limited safety directive focused on a specific mechanical defect. Airworthiness Directives by nature are narrow in scope — they address particular safety issues rather than expanding regulatory frameworks. The scope remains tightly confined to the original safety concern (cracking in main rotor blades near trim tabs) with no evidence of mission creep or expansion beyond the initial safety imperative."},"complexity_factors":["Single, specific mechanical issue (cracking in one component location)","Limited applicability — only 2 specific part numbers with 'A' serial prefix, with explicit exclusions","Straightforward binary compliance: inspect by specific date, repair or replace based on crack location","Only 2 defined part numbers and 6 helicopter models specified","Single cross-reference to FAA directive for background context","No nested exceptions or conditional logic beyond the initial applicability carve-out"],"plain_english_summary":"This CASA Airworthiness Directive mandates immediate inspection of main rotor blades on affected Bell 206 series helicopters for cracks near the trim tab, with polishing of scratches per manufacturer instructions. Cracks in the trim tab may be repaired; any other blade cracking requires removing the blade from service.\n\nIt’s compulsory for operators of listed Bell 206 models with specified blade serials and is time-critical due to risk of catastrophic blade failure."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The directive targets specific Bell 206 models with two main-rotor-blade part numbers and 'A'‑prefix serial numbers, excluding blades listed in the referenced Bell Alert Service Bulletins. It imposes an inspection and either rework (for trim-tab cracks) or removal (for other cracks) within 50 hours; it does not expand or narrow that applicability beyond what the AD text describes."},"complexity_factors":["Narrow applicability by model, part numbers and serial-number prefix increases need for accurate parts/serial identification (Applicability).","Simple visual inspection requirement but with a specified tool (10× magnifier) and polishing step — technical but routine (Requirement).","Two-tier outcome: allowable rework for trim-tab cracks versus mandatory removal for other cracks — requires judgment on crack location and adherence to service-bulletin criteria (Requirement, Part II).","Dependence on external service bulletins for rework instructions introduces procedural dependency and potential variability in maintenance cost/time (Requirement).","Short compliance window (50 hours time in service) imposes scheduling and operational disruption risk for operators (Compliance).","Exclusion of blades listed in Bell Alert Service Bulletins adds an exception list that operators must cross-check (Applicability).","Reference to an FAA AD indicates coordination with another regulator but does not change domestic procedural steps (Note).","Safety-critical outcome (prevent rotor-blade failure) raises the consequence of incorrect inspection or non-compliance (Background)."],"plain_english_summary":"Requires operators of specified Bell 206 helicopters fitted with certain main rotor blades to inspect the inboard trim tab and adjacent blade surfaces for cracks using a 10× magnifier. Blades with trim-tab cracks may be reworked per Bell Alert Service Bulletins; blades with cracks elsewhere must be removed from service. Work must be completed within *50 hours* time in service. Operators pay for inspections and repairs; maintenance must follow the service bulletins to address reported trailing‑edge cracking."}},"importantCases":[],"_links":{"self":"/api/acts/ad-bell-206-128-main-rotor-blade-and-trim-tab","history":"/api/acts/ad-bell-206-128-main-rotor-blade-and-trim-tab/history","analysis":"/api/acts/ad-bell-206-128-main-rotor-blade-and-trim-tab/analysis","conflicts":"/api/acts/ad-bell-206-128-main-rotor-blade-and-trim-tab/conflicts","importantCases":"/api/acts/ad-bell-206-128-main-rotor-blade-and-trim-tab/important-cases","documents":"/api/acts/ad-bell-206-128-main-rotor-blade-and-trim-tab/documents"}}