{"id":"F2006B09372","name":"AD/ECUREUIL/66 Amdt 1 - Tail Rotor Hub Pitch Change Bearings","slug":"ad-ecureuil-66-amdt-1-tail-rotor-hub-pitch-change-bearings","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":53658,"registerId":"commonwealth-F2006B09372-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/ECUREUIL/66 Amdt 1 - Tail Rotor Hub Pitch Change Bearings","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)  \n\nAIRWORTHINESS DIRECTIVE\n\n![](image.001.png)\n\n![](image.001.png)  \nFor the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/ECUREUIL/66 and issues the following AD under subregulation 39.1 (1) of CAR 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\nEurocopter AS 350 (Ecureuil) Series Helicopters\n\nAD/ECUREUIL/66\n\nAmdt 1\n\n  \nTail Rotor Hub Pitch Change Bearings 11/2002\n\nApplicability: All AS 350 helicopters, versions B, BA, BB, B1, B2, B3, and D fitted with tail rotor pitch change plate SNR bearing, P/No 6010F234M16 (704A33-651-190).\n\nRequirement: Replace tail rotor pitch change bearings P/No 6010F234M16 (704A33-651-190).\n\nNote: DGAC TAD T2001-074-081(A) refers.\n\nCompliance: For AS 350 B3 version:\n\nAt 300 flight hours bearing time since new, thereafter at 300 flight bearings hours time since new.\n\nFor AS 350 B, BA, BB, B1, B2, and D versions:\n\nAt 1200 flight hours bearing time since new, thereafter at 1200 flight hours bearing time since new.\n\nThis Amendment becomes effective on 31 October 2002.\n\nBackground: This Airworthiness Directive is prompted by advice from the DGAC that cracks have been found in some tail rotor pitch change plate bearings, which can lead to malfunction of the plate and loss of control of the helicopter.\n\nThis Amendment has been issued to reflect compliance that is now relevant.\n\nThe original issue of this Airworthiness Directive became effective 7 March 2001.\n\n![Signature of James Coyne, Delegate of the Civil Aviation Safety Authority.](image.002.png)  \n\nJames Coyne\n\nDelegate of the Civil Aviation Safety Authority 24 September 2002\n\n![](image.001.png)  \n\nThe above AD is notified in the Commonwealth of Australia Gazette on 9 October 2002.\n\n  \nPage 1 of 1","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"},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"This Amendment revokes the prior AD and reissues the requirement to replace the identified tail rotor pitch change bearings, setting explicit replacement intervals (300 FH for B3; 1200 FH for other listed variants). The amendment therefore updates the compliance regime that operators must follow (as stated in the Background and Compliance sections)."},"complexity_factors":["Applicability limited to a single part number but across multiple airframe variants (requires checking fleet fitment).","Different mandatory compliance intervals for AS350 B3 (300 FH) versus other variants (1200 FH).","Safety-critical nature increases operational impact despite straightforward technical action.","Revocation and replacement of an earlier AD requires updating maintenance records and procedures."],"plain_english_summary":"This Airworthiness Directive requires owners/operators of Eurocopter AS350 helicopters fitted with tail rotor pitch change plate bearing P/No 6010F234M16 (704A33-651-190) to replace that specific bearing at set flight-hour intervals (AS350 B3: 300 hours; other listed variants: 1200 hours). CASA revoked the earlier AD and issued this one after cracks were found in those bearings that can cause pitch-plate malfunction and potential loss of control. Operators bear the replacement cost and downtime; compliance is mandatory under CAR subregulation 39.1(1)."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This amendment maintains the original scope of the Airworthiness Directive. It updates the compliance intervals (how often the bearing must be replaced) but does not expand the types of aircraft affected, the parts covered, or the nature of the safety action required. The amendment reflects revised technical data from the French aviation authority (DGAC) regarding appropriate replacement intervals."},"complexity_factors":["Single, specific technical requirement (bearing replacement)","Clear applicability limited to specific helicopter models and part numbers","Simple binary compliance structure based on helicopter version (B3 vs others)","No cross-references to other legislation beyond a single note referencing French aviation authority document","Minimal defined terms (only standard aviation terminology)","Short document (1 page) with straightforward structure: Applicability → Requirement → Compliance → Background"],"plain_english_summary":"CASA requires owners/operators of Eurocopter AS350 (Ecureuil) helicopters with tail rotor pitch change bearing P/N 6010F234M16 to replace that bearing on a mandatory schedule due to reported cracking that can lead to loss of tail-rotor control and possible crash. Compliance is legally required: AS350 B3 helicopters every 300 flight hours; AS350 B, BA, BB, B1, B2 and D every 1,200 flight hours."}},"importantCases":[],"_links":{"self":"/api/acts/ad-ecureuil-66-amdt-1-tail-rotor-hub-pitch-change-bearings","history":"/api/acts/ad-ecureuil-66-amdt-1-tail-rotor-hub-pitch-change-bearings/history","analysis":"/api/acts/ad-ecureuil-66-amdt-1-tail-rotor-hub-pitch-change-bearings/analysis","conflicts":"/api/acts/ad-ecureuil-66-amdt-1-tail-rotor-hub-pitch-change-bearings/conflicts","importantCases":"/api/acts/ad-ecureuil-66-amdt-1-tail-rotor-hub-pitch-change-bearings/important-cases","documents":"/api/acts/ad-ecureuil-66-amdt-1-tail-rotor-hub-pitch-change-bearings/documents"}}