{"id":"F2019L00127","name":"AD/BELL 206/99 Amdt 4 Cyclic Control Stick Assembly","slug":"ad-bell-206-99-amdt-4-cyclic-control-stick-assembly","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":98751,"registerId":"commonwealth-F2019L00127-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Bell Helicopter Textron Canada (BHTC) 20","sectionType":"part","heading":"Bell Helicopter Textron Canada (BHTC) 206 and Leonardo Helicopters (Agusta) AB206 Series Helicopters","content":"# Bell Helicopter Textron Canada (BHTC) 206 and Leonardo Helicopters (Agusta) AB206 Series Helicopters\n\n| AD/BELL 206/99 Amdt 4 | Cyclic Control Stick Assembly | 4/2019 |\n| --------------------- | ----------------------------- | ------ |\n\n| Applicability: | All models of Bell Helicopter Textron Canada (BHTC) 206A, 206B, 206B‑JRIII, 206L, 206L-1, 206L-3, and Agusta Bell AB206A and AB206B helicopters. |\n| -------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement: | 1. (a) For all BHTC 206A, 206B, 206B‑JRIII, 206L, 206L-1, and 206L-3 helicopters, inspect the helicopter data plate and determine the serial number of each helicopter.(b) If the inspection identifies any serial number listed in the applicability / affected helicopter section of BHTC Alert Service Bulletin 206-85-29 dated 21 June 1985, as in force at the date of commencement of this Airworthiness Directive (AD) or BHTC Alert Service Bulletin 206L-85-36 dated 21 June 1985, as in force at the date of commencement of this AD, as applicable, then carry out all the technical requirements of the applicable service bulletin.2. (a) For all Bell 206A helicopters equipped with dual control kits Part Numbers 206-7-6-006-3, -5 and -7, carry out all the technical requirements of BHTC Alert Service Bulletin 206-85-29 dated 21 June 1985, as in force at the date of commencement of this AD.(b) For all Agusta Bell AB206A and AB206 helicopters and all Agusta Bell AB206A helicopters equipped with dual control kit part number 206‑706‑006 (all dash numbers), carry out all the technical requirements of Agusta Bell Service Bulletin 206-169 Revision A dated 11 December 1985, as in force at the date of commencement of this AD. |\n| Compliance: | Unless previously accomplished, within 25 hours’ time in service after the commencement date of this AD and thereafter, for both BHTC and Agusta Bell helicopters, at intervals not to exceed every 600 hours’ time in service or 24 months, whichever occurs first. |\n| | This AD commences on 22 February 2019. |\n| Background: | An incident has been reported of a cyclic control stick failing while the pilot was performing his pre-flight checks. The fracture, which occurred at the base of the stick tube has been attributed to low cycle fatigue and corrosion. |\n\n| | Amendment 2 of this AD was issued to include Agusta Bell AB206A and AB206B helicopters. Agusta Bell have followed BHTC Alert Service Bulletin 206-85-29, and have also called for a repetitive inspection which has been included to cover both Agusta Bell and Bell helicopters.Amendment 3 of this AD was issued to clarify the applicability range affected by this AD. There were no additional technical requirements introduced by this amendment.Amendment 4 is issued to further clarify the applicability section and to align the applicability of the AD with that of the requirement documents. |\n| --- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n\n![](image.001.jpeg)\n\nPieter van Dijk \nDelegate of the Civil Aviation Safety Authority\n\n8 February 2019","sortOrder":0},{"sectionNumber":"AD/BELL 206/99 Amdt 4","sectionType":"part","heading":"AD/BELL 206/99 Amdt 4","content":"## AD/BELL 206/99 Amdt 4","sortOrder":1},{"sectionNumber":"Cyclic Control Stick Assembly","sectionType":"part","heading":"Cyclic Control Stick Assembly","content":"## Cyclic Control Stick Assembly","sortOrder":2},{"sectionNumber":"4/2019","sectionType":"part","heading":"4/2019","content":"## 4/2019","sortOrder":3}],"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":4,"scope_assessment":{"changed":true,"description":"Originally focused on Bell helicopters only. Amendment 2 expanded scope to include Agusta Bell AB206A and AB206B helicopters. Amendment 3 and 4 further expanded/clarified applicability rather than narrowing it. The directive has grown from its original Bell-only scope to cover licensed/derivative production by Agusta, effectively broadening from one manufacturer to two distinct manufacturing lines with different service bulletin requirements."},"complexity_factors":["Multiple amendment history (Amendments 2, 3, and 4) with cross-references to previous versions","Dual manufacturer applicability (Bell Helicopter Textron Canada and Agusta/Leonardo Helicopters)","Conditional logic: different service bulletins apply depending on helicopter model and specific dual control kit part numbers","External document incorporation by reference (BHTC Alert Service Bulletins 206-85-29, 206L-85-36, and Agusta Bell Service Bulletin 206-169 Revision A)","Specific part number identification required for dual control kits (206-7-6-006-3, -5, -7 and 206-706-006)","Time-based compliance with 'whichever occurs first' logic (600 hours OR 24 months)","Serial number cross-checking against manufacturer lists required to determine applicability"],"plain_english_summary":"This AD mandates inspection and maintenance of the cyclic control stick on specified Bell and Agusta (AB206/206 series) helicopters after reports of cracking from low‑cycle fatigue and corrosion that can cause loss of directional control. Affected operators must check serial numbers against manufacturer service bulletins and, if applicable, follow their procedures with repetitive inspections every 600 flight hours or 24 months, starting within 25 flight hours. This fourth amendment clarifies coverage and aligns requirements with the service bulletins."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"The AD as amended expanded applicability beyond the original set of Bell 206 helicopters to explicitly include Agusta Bell AB206A and AB206B models (Amendment 2) and later amendments clarified and aligned the applicability language with the manufacturer service bulletins (Amendments 3 and 4). Those changes increased the population of affected aircraft and brought Agusta‑produced variants under the same repetitive inspection/corrective regime. Amendment 4 itself clarifies applicability and aligns wording; it did not add new technical requirements beyond those already contained in the referenced service bulletins."},"complexity_factors":["Short standalone AD with limited sections (Applicability, Requirement, Compliance, Background)","Cross‑references to three external manufacturer service bulletins (BHTC Alert Service Bulletin 206‑85‑29; BHTC Alert Service Bulletin 206L‑85‑36; Agusta Bell Service Bulletin 206‑169 Rev A)","Conditional logic based on serial numbers and fitted dual‑control kit part numbers (Requirement 1(b), 2(a)–(b))","Repetitive compliance schedule (initial action within 25 hours; repeat every 600 hours or 24 months)","Multiple helicopter model variants listed in applicability (several BHTC 206 and Agusta AB206 variants)","History of amendments that alter applicability (Amendments 2–4) requiring users to check amendment history for full scope"],"plain_english_summary":"**What this instrument does (mechanically)\n\n- Requires inspections and, where indicated, corrective work on the cyclic control stick assembly (the pilot's control column) for a set of Bell 206 and Agusta Bell AB206 helicopters.\n- Operators must check the helicopter data plate to determine the helicopter serial number and then follow the specific manufacturer service bulletin instructions for affected serial numbers (Requirement 1(a)–(b)).\n- For certain Bell 206A helicopters fitted with specific dual‑control kits, the AD mandates the technical steps in Bell Helicopter Textron Canada (BHTC) Alert Service Bulletin 206‑85‑29 (Requirement 2(a)).\n- For Agusta Bell AB206A/AB206B helicopters (and AB206A helicopters with a specified dual‑control kit), the AD directs compliance with Agusta Bell Service Bulletin 206‑169 Rev A (Requirement 2(b)).\n- Timing: if not already done, the initial action must be completed within 25 hours’ time in service after the AD starts; thereafter the inspections/actions repeat at intervals not exceeding every 600 hours’ time in service or every 24 months, whichever comes first (Compliance).\n- Commencement date listed: 22 February 2019.\n\n**Who is affected\n\n- Owners and operators of the listed Bell Helicopter Textron Canada 206 variants: 206A, 206B, 206B‑JRIII, 206L, 206L‑1, 206L‑3.\n- Owners and operators of Agusta Bell AB206A and AB206B helicopters (included by amendment).\n- Maintenance organisations, certificated mechanics, and parts suppliers who perform the inspections and repairs mandated by the referenced service bulletins.\n\n**Why it matters (stated reason and practical effect)\n\n- Stated reason: an incident occurred where a cyclic control stick fractured at the base due to low‑cycle fatigue and corrosion during pre‑flight checks. The AD’s stated purpose is to detect and correct similar defects to prevent in‑flight or pre‑flight failure (Background).\n- Practical effect: operators must schedule inspections and any required repairs or replacements per the manufacturer service bulletins. That imposes direct compliance costs (labour, parts, downtime) on operators, and it creates recurring maintenance obligations (every 600 hours or 24 months).\n\n**How the AD works in practice and who pays/decides\n\n- Who pays: helicopter owners/operators pay for inspections, parts and labour required by the service bulletins. If an operator has warranty coverage or other commercial arrangements with a manufacturer/maintenance provider, costs may be shared according to those contracts — but the AD itself imposes the obligation on the operator.\n- Who decides: the Civil Aviation Safety Authority (CASA) (via its delegate) issues the AD; operators and maintenance providers decide how to schedule and carry out the mandated inspections/repairs subject to the technical steps in the referenced service bulletins (Requirement 1–2). Certificate‑holding maintenance organisations implement the work and sign off compliance.\n- Behavioural change required: regular inspection of the cyclic stick per the mandated interval; where serial numbers or kit part numbers trigger the requirement, operators must follow the manufacturer’s corrective procedures (including any replacements or modifications specified).\n\n**Costs, incentives and trade‑offs (practical assessment)\n\n- Direct costs and downtime: compliance requires initial inspection within 25 hours and repeated inspections at the specified intervals. Inspections and any corrective work create direct costs (labour, replacement parts) and opportunity cost from aircraft downtime. That burden is concentrated on owners/operators of the affected models.\n- Supply and service demand: the AD directs compliance with manufacturer service bulletins, which channels work and parts purchases to qualified maintenance providers and parts suppliers. This concentrates the commercial benefit on those suppliers and maintenance providers able to service these helicopters.\n- Safety benefit concentrated, cost concentrated: the safety benefit (reduced risk of cyclic stick failure) accrues to pilots, passengers and operators; the compliance cost is borne directly by the operators of affected machines.\n- Implementation risk: effective compliance requires operators to obtain and follow the external manufacturer service bulletins referenced in the AD. Any ambiguity or variation in those external documents can create compliance uncertainty or additional queries to the regulator or manufacturer.\n- No change to ownership or contract freedom: the AD is a regulatory maintenance requirement; it does not transfer ownership, change contractual relationships directly, or restrict aircraft sale — but it may affect market value and operating economics of affected airframes.\n\n**What changed across amendments (short note)\n\n- Earlier amendments expanded the listed applicability to explicitly include Agusta Bell AB206A and AB206B helicopters (Amendment 2) and later amendments clarified the applicability language to align the AD with the service bulletins (Amendments 3 and 4). The technical work required remains driven by the manufacturer service bulletins referenced in the AD.\n\n**Where to look in the text for the obligations\n\n- Inspection/serial number check and service bulletin compliance: Requirement 1(a)–(b).\n- Specific requirements for Bell 206A dual control kits and Agusta Bell helicopters: Requirement 2(a)–(b).\n- Timing and repeat interval: Compliance paragraph.\n- Stated reason for the AD (failure incident): Background.\n\n(References in parentheses indicate the paragraph headings/specific requirement numbers from the AD.)"}},"importantCases":[],"_links":{"self":"/api/acts/ad-bell-206-99-amdt-4-cyclic-control-stick-assembly","history":"/api/acts/ad-bell-206-99-amdt-4-cyclic-control-stick-assembly/history","analysis":"/api/acts/ad-bell-206-99-amdt-4-cyclic-control-stick-assembly/analysis","conflicts":"/api/acts/ad-bell-206-99-amdt-4-cyclic-control-stick-assembly/conflicts","importantCases":"/api/acts/ad-bell-206-99-amdt-4-cyclic-control-stick-assembly/important-cases","documents":"/api/acts/ad-bell-206-99-amdt-4-cyclic-control-stick-assembly/documents"}}