{"id":"F2007L01401","name":"AD/BELL 206/169 - Exhaust Duct Grooved Clamps","slug":"ad-bell-206-169-exhaust-duct-grooved-clamps","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":65757,"registerId":"commonwealth-F2007L01401-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Bell Helicopter Textron Canada (BHTC) 20","sectionType":"division","heading":"Bell Helicopter Textron Canada (BHTC) 206 and Agusta Bell 206 Series Helicopters","content":"### Bell Helicopter Textron Canada (BHTC) 206 and Agusta Bell 206 Series Helicopters\n\n| AD/BELL 206/169 | Exhaust Duct Grooved Clamps | 6/2007 |\n| --------------- | --------------------------- | ------ |\n\n| Applicability: | Agusta AB206A and AB206B series helicopters.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |\n| -------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | 1. Inspect the grooved clamps P/N 4656AA or P/N 4606AC fixing the engine exhaust duct in accordance with Agusta “Bollettino Tecnico” 206-242 dated18 December 2006 or later approved revisions.2. In any cracks and/or corrosion are found, discard and replace the affected grooved clamp.Note: EASA AD 2007-0043 dated 21 February 2007 refers.                                                                                                                                                                                                                                                         |\n| Compliance:    | 1. Within the next 50 hours time in service (TIS) or within 30 days after the effective date of this AD whichever occurs first. Thereafter repeat every 100 flight hours or yearly, whichever occurs first.2. Before further flight after the effective date of this AD.                                                                                                                                                                                                                                                                                                                                  |\n|                | This Airworthiness Directive becomes effective on 7 June 2007.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |\n| Background:    | An A109A helicopter had a failure of the grooved clamp fixing the engine exhaust duct, with the consequent loss of the duct. The duct hit the main and tail rotor producing the loss of the tail rotor and the emergency landing of the helicopter.Taking into account the occurrence reported above as well as the commonality between the exhaust duct installations for A109 and AB206 helicopters, Agusta issued “Bollettino Tecnico” 206-242 to require a visual inspection of the grooved damps for cracks and/or for corrosion, in order to ensure the continued airworthiness of the helicopters. |\n\n![](image.001.png)  \nDavid Punshon  \nDelegate of the Civil Aviation Safety Authority\n\n26 April 2007","sortOrder":0},{"sectionNumber":"AD/BELL 206/169","sectionType":"part","heading":"AD/BELL 206/169","content":"## AD/BELL 206/169","sortOrder":1},{"sectionNumber":"Exhaust Duct Grooved Clamps","sectionType":"part","heading":"Exhaust Duct Grooved Clamps","content":"## Exhaust Duct Grooved Clamps","sortOrder":2},{"sectionNumber":"6/2007","sectionType":"part","heading":"6/2007","content":"## 6/2007","sortOrder":3}],"analysis":{"flash_summary_failed":{"failed":true,"reason":"Unauthenticated. Configure AI_GATEWAY_API_KEY or use a provider module. Learn more: https://ai-sdk.dev/unauthenticated-ai-gateway","source":"analysis-cron"},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"Scope remains focused on inspecting and replacing specified grooved clamps on Agusta AB206A/B to prevent exhaust-duct separation. The directive’s obligations (Applicability, Requirement, Compliance) align with the stated safety objective and do not expand beyond that targeted corrective action."},"complexity_factors":["Targeted applicability to Agusta AB206A and AB206B helicopters (Applicability) — narrows affected population and simplifies compliance.","Specific part numbers required for inspection and replacement (Requirement: P/N 4656AA, P/N 4606AC) — reduces ambiguity but requires parts tracking.","Reference to an external service bulletin (Agusta Bollettino Tecnico 206-242) — adds dependence on manufacturer documentation and any approved revisions (Requirement).","Clear compliance windows: initial within 50 TIS or 30 days, then repeat every 100 flight hours or yearly (Compliance) — multiple timing triggers increase procedural planning.","Mandatory discard-and-replace remedy for detected cracks/corrosion (Requirement) — creates direct spare-parts cost and downtime.","Safety-critical consequence described in Background (exhaust duct loss hitting rotors) — imposes strict ‘before further flight’ action when defects found, limiting operator discretion."],"plain_english_summary":"Requires operators of Agusta AB206A and AB206B helicopters to inspect two specific grooved clamps (P/N 4656AA or 4606AC) that secure the engine exhaust duct and to discard and replace any clamp with cracks or corrosion. Initial inspection is due within 50 flight hours or 30 days, whichever is first, with repeat inspections every 100 flight hours or yearly; defects must be fixed before further flight. The rule addresses risk of exhaust-duct separation that can strike rotors and cause an emergency landing."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This AD maintains its original narrow scope — addressing a specific safety defect in specific helicopter models. It has not expanded beyond the original intent of preventing exhaust duct clamp failures."},"complexity_factors":["Single, specific mechanical component targeted (grooved clamps)","Straightforward two-step requirement: inspect, then replace if defective","Simple compliance timeline with clear alternatives (hours OR days)","Only two part numbers specified","No nested exceptions, conditional clauses, or cross-references to other legislation","Background narrative explains the safety rationale in plain language","Total length is approximately 300 words"],"plain_english_summary":"This AD mandates inspections of the grooved clamps (4656AA/4606AC) securing the engine exhaust duct on Agusta AB206A/B helicopters, with an initial check shortly after the AD's effective date and recurring checks thereafter. Any cracked or corroded clamps must be replaced before flight.\n\nIt responds to a catastrophic A109A failure where a broken clamp let the exhaust duct detach and damage rotors; it affects AB206 owners, operators and maintenance personnel in Australia."}},"importantCases":[],"_links":{"self":"/api/acts/ad-bell-206-169-exhaust-duct-grooved-clamps","history":"/api/acts/ad-bell-206-169-exhaust-duct-grooved-clamps/history","analysis":"/api/acts/ad-bell-206-169-exhaust-duct-grooved-clamps/analysis","conflicts":"/api/acts/ad-bell-206-169-exhaust-duct-grooved-clamps/conflicts","importantCases":"/api/acts/ad-bell-206-169-exhaust-duct-grooved-clamps/important-cases","documents":"/api/acts/ad-bell-206-169-exhaust-duct-grooved-clamps/documents"}}