{"id":"F2006B09393","name":"AD/ECUREUIL/90 Amdt 1 - Flight Control Stop Screws","slug":"ad-ecureuil-90-amdt-1-flight-control-stop-screws","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":53726,"registerId":"commonwealth-F2006B09393-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/ECUREUIL/90 Amdt 1 - Flight Control Stop Screws","content":"![](image.001.png)\n\n![](image.001.png)  \nAIRWORTHINESS DIRECTIVE\n\nOn the effective date specified below, and for the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/ECUREUIL/90 and issues the following AD under subregulation 39.1 (1) of CASR 1998. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.\n\n![](image.001.png)\n\nEurocopter AS 350 (Ecureuil) Series Helicopters\n\nAD/ECUREUIL/90\n\nAmdt 1\n\n  \nFlight Control Stop Screws 9/2004\n\nApplicability: Models AS 350 B, BA, BB, B1, B2, B3, and D, and Model EC 130 B4 helicopters; without MOD 073206 or MOD 073102 incorporated.\n\nComponents affected: roll, pitch, and collective flight control stops.\n\nRequirement: 1. Action in accordance with paragraph 2.B.1. of Eurocopter Alert Service Bulletins AS 350 No. 67.00.25 R1 or EC 130 No. 67A004 R1, as applicable.\n\n2. Action in accordance with paragraph 2.B.2. of Eurocopter Alert Service Bulletins AS 350 No. 67.00.25 R1 or EC 130 No. 67A004 R1, as applicable.\n\nNote: DGAC AD F-2003-322 R1 refers.\n\nCompliance: 1. Within 100 flight hours after 30 October 2003, unless already accomplished.\n\n2. Within 500 flight hours or 1 year after 30 October 2003, whichever occurs first. The compliance times remain unchanged by this issue.\n\nThis Amendment becomes effective on 2 September 2004.\n\nBackground: A report was received of an incident during a ground run-up with a Model EC 120 helicopter, where it was possible to push the collective lever downward beyond it’s normal position. Investigation revealed that the locknut of the low pitch stop had come loose and that the stop was out of adjustment. The worst case scenario is that of collective low pitch stop maladjustment, which can result in rotor under-speed in an auto-rotation situation.\n\nAmendment 1 is issued in response to a revision of the related DGAC AD, which introduces additional applicability information and revised Requirement documents, with no change to the technical content.\n\nEurocopter AS 350 (Ecureuil) Series Helicopters\n\nAD/ECUREUIL/90 Amdt 1 (continued)\n\nThe original issue of this Airworthiness Directive became effective on 30 October 2003.\n\n![Signature of David Villiers, Delegate of the Civil Aviation Safety Authority.](image.002.png)  \n\nDavid Villiers\n\nDelegate of the Civil Aviation Safety Authority 13 July 2004\n\n![](image.001.png)  \n\nThe above AD is notified in the Commonwealth of Australia Gazette on 11 August 2004.","sortOrder":0}],"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":"Amendment 1 updates applicability wording and references the revised Eurocopter/DGAC documents but does not change the technical corrective actions or compliance times. The AD therefore remains within the original safety‑correction scope (inspection/adjustment of flight control stop screws for the specified models)."},"complexity_factors":["Short, focused instrument (single safety action) with few internal provisions","One conditional applicability clause: applies only to models without MOD 073206 or MOD 073102","Cross‑references to external documents (two Eurocopter Alert Service Bulletins) for the technical steps","Two distinct compliance timeframes (100 flight hours; 500 flight hours or 1 year)","Reference to and replacement of a prior AD (administrative cross‑reference)"],"plain_english_summary":"**What this instrument does (mechanics)\n\n- This Airworthiness Directive (AD) orders operators of certain Eurocopter helicopters to inspect and, if necessary, adjust the flight‑control stop screws for roll, pitch and collective controls.  The AD requires following specific steps set out in the Eurocopter Alert Service Bulletins cited in the Requirement section (paragraphs 2.B.1 and 2.B.2 of AS 350 No. 67.00.25 R1 or EC 130 No. 67A004 R1).\n- It applies to Eurocopter (now Airbus Helicopters) Models AS 350 B, BA, BB, B1, B2, B3 and D, and Model EC 130 B4, but only for aircraft that do not already have modification MOD 073206 or MOD 073102 incorporated (the AD explicitly excludes helicopters with those mods).\n- Compliance deadlines are twofold: the first action must be done within 100 flight hours after 30 October 2003 (unless already done); the second action must be done within 500 flight hours or 1 year after 30 October 2003, whichever comes first. The AD replaces a previous AD (AD/ECUREUIL/90) and restates those same compliance times.\n\nWho decides and who pays\n\n- The Civil Aviation Safety Authority (CASA) delegate issues and enforces the AD; operators and their maintenance organisations are required to carry out the work. Costs (labour, parts, downtime) fall on the helicopter operators/owners and on maintenance providers who carry out the tasks.\n\nWhy CASA says it matters (stated rationale)\n\n- The background explains the AD responds to a reported incident in which the low‑pitch stop locknut became loose on an EC 120 during a ground run‑up, allowing the collective lever to move beyond its normal position. If a collective low‑pitch stop is maladjusted, the stated hazard is potential rotor under‑speed during an autorotation. The amendment follows a related French DGAC AD revision and updates applicability and the referenced Eurocopter documents without changing the technical instructions.\n\nPractical effect on behaviour and choices\n\n- Operators must inspect/adjust flight‑control stop screws per the manufacturer service bulletins. If an operator has already incorporated one of the two listed modifications (MOD 073206 or MOD 073102), the AD does not apply to that aircraft.\n- The AD forces a short‑term maintenance action (two checks/adjustments on the specified schedule) and creates an operational choice: either comply with the inspection/adjustment requirements or ensure the applicable modification(s) are incorporated if those mods are an available route to remove the aircraft from the AD applicability.\n\nCosts, incentives, trade‑offs and practical risks (implementation lens)\n\n- Direct costs: maintenance labour, possible replacement parts, aircraft downtime while inspections/adjustments are done, and record‑keeping to demonstrate compliance. These costs are concentrated on the operators of the affected helicopter models.\n- Incentives created: operators have an incentive to either perform the inspections/adjustments or to incorporate the listed modification(s) if that is an economically preferable way to eliminate recurring or repetitive actions. Maintenance suppliers (including third‑party shops and authorised dealers) will capture the maintenance work demand.\n- Compliance burden: the AD relies on external documents (Eurocopter Alert Service Bulletins). Operators must obtain and follow those documents accurately; ambiguity or complexity in the service bulletins could increase maintenance risk or lead to inconsistent compliance across operators.\n- Implementation risk: enforcement depends on CASA oversight and operators' maintenance record‑keeping. Incorrect or incomplete compliance (e.g. failure to follow the precise paragraphs cited) could leave the unsafe condition uncorrected.\n- Market effects: the AD does not ban operation but imposes a maintenance obligation. It can favour maintenance providers competent in Eurocopter procedures. It does not directly alter competition in air transport markets, but it does redistribute maintenance costs to operators of the specified types.\n\nConcrete mechanism summarised\n\n- Who pays: helicopter operators/owners and their maintenance providers.  \n- Who decides: CASA delegate issues the AD; operators decide whether to comply by inspection/adjustment or to incorporate the specified mods (if available and allowed).  \n- What behaviour changes: mandatory inspection/adjustment of roll, pitch and collective stop screws per the cited Eurocopter Alert Service Bulletins within the two specified compliance windows; exclusion of aircraft that already have MOD 073206 or MOD 073102.\n\nSource pointers (where to look in the AD)\n\n- Applicability: lists affected models and the exclusion for MOD 073206 or MOD 073102.  \n- Requirement: mandates work “in accordance with paragraph 2.B.1.” and “paragraph 2.B.2.” of the respective Eurocopter Alert Service Bulletins.  \n- Compliance: gives the 100 flight‑hour and 500 flight‑hour/1‑year deadlines.  \n- Background and Amendment summary: explains the incident prompting the AD and notes the amendment aligns with a DGAC AD revision without changing technical content."},"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This amendment maintains the original scope. The document explicitly states that Amendment 1 introduces 'no change to the technical content' and only updates applicability information and referenced documents in response to a French aviation authority (DGAC) revision. The safety action, affected components, and compliance times remain identical to the original October 2003 directive."},"complexity_factors":["Short, single-purpose document (1 page)","Only 2 defined compliance timeframes (100 hours and 500 hours/1 year)","Clear applicability section listing specific helicopter models","Simple two-part requirement structure referencing external technical documents (service bulletins)","Minimal conditional logic (only 'unless already accomplished' and 'whichever occurs first')","No nested exceptions or complex cross-referencing within the document itself","Background provides clear safety rationale in plain language"],"plain_english_summary":"This CASA safety order (replacing an earlier one) requires operators of Eurocopter AS350 and EC130 B4 helicopters that lack factory MOD 073206 or 073102 to inspect and adjust the flight‑control “stop screws” per Eurocopter service bulletins. Inspections are mandated within 100 flight hours and follow‑up action within 500 hours or one year after 30 Oct 2003. It prevents collective overtravel during autorotation that could slow the rotor and cause loss of control."}},"importantCases":[],"_links":{"self":"/api/acts/ad-ecureuil-90-amdt-1-flight-control-stop-screws","history":"/api/acts/ad-ecureuil-90-amdt-1-flight-control-stop-screws/history","analysis":"/api/acts/ad-ecureuil-90-amdt-1-flight-control-stop-screws/analysis","conflicts":"/api/acts/ad-ecureuil-90-amdt-1-flight-control-stop-screws/conflicts","importantCases":"/api/acts/ad-ecureuil-90-amdt-1-flight-control-stop-screws/important-cases","documents":"/api/acts/ad-ecureuil-90-amdt-1-flight-control-stop-screws/documents"}}