{"id":"F2006B09367","name":"AD/ECUREUIL/61 Amdt 1 - TR Head Pitch Change Plate Bearing Spacer","slug":"ad-ecureuil-61-amdt-1-tr-head-pitch-change-plate-bearing-spacer","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":53642,"registerId":"commonwealth-F2006B09367-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/ECUREUIL/61 Amdt 1 - TR Head Pitch Change Plate Bearing Spacer","content":"![](image.001.png)\n\n![](image.001.png)  \nAIRWORTHINESS DIRECTIVE\n\nFor the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/ECUREUIL/61 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/61\n\nAmdt 1\n\n  \n\nTR Head Pitch Change Plate Bearing Spacer\n\n  \n13/2004\n\nApplicability: AS 350 helicopters, versions B, B1, B2, B3, BA, BB and D, fitted with the tail rotor pitch change rotating plates, all part numbers, on which Eurocopter modification (Mod) 07 6554 has not been embodied.\n\nThis Airworthiness Directive (AD) does not apply to post-mod 076550 pitch change plate assembly part number 350A33-2030-00.\n\nRequirement: 1. Identify position of the spacer and the tail rotor pitch change rotating plate as per provisions of paragraph 2.B.1 of Eurocopter AS350 Alert Service Bulletin (ASB)\n\n05.00.33 R1 dated 15 March 2004 or later revision approved by DGAC / EASA.\n\n2. a. Monitor position of the spacer and the tail rotor pitch change rotating plate for alignment as per provisions of paragraph 2.B.2 of ASB 05.00.33 R1.\n\nThe inspection detailed in requirement 2 may be performed by the pilot-in- command, in which case, a certification is to be made by entering AD/ECUREUILl/61 Amdt 1 against the daily inspection certification on the maintenance release. A copy of this directive and of the requirement document must be carried in the helicopter.\n\n2. b. If the paint index marks are aligned, embody Mod 076550 as per the provisions of paragraph 2.B.3 of ASB 05.00.33 R1 or later revision approved by DGAC / EASA.\n\n    2. c. If the paint index marks are mis-aligned, embody Mod 076550 as per the provisions of paragraph 2.B.4 of ASB 05.00.33 R1 or later revision approved by DGAC / EASA.\n\nNote 1: DGAC Airworthiness Directive F-2000-222-079R1 as approved by EASA reference number 2004-9369 dated 7 September 2004 refers.\n\nCompliance: 1. Unless previously accomplished, at the latest within 10 flying hours after the effective date of this AD.\n\n    2.a. Daily, after the last flight of the day.\n\n    2.b. Not later than the next “T” basic inspection.\n\nEurocopter AS 350 (Ecureuil) Series Helicopters\n\nAD/ECUREUIL/61 Amdt 1 (continued)\n\n    2.c. With-in 25 flying hours from detection of the misalignment.\n\nNote 2: Compliance to the original version of AD/ECUREUILl/61 is an acceptable alternate to this amendment and no further action is required.\n\nThis Amendment becomes effective on 23 December 2004.\n\nBackground: This amendment of the Airworthiness Directive reflects changes in the document referred to, in the original issue of the AD, namely revision 1 of Eurocopter AS 350 ASB 05.00.33 and revision 1 of DGAC AD F-2000-222-079. The changes are in the effectivity list and there is no difference in the technical contents.\n\nThere have been reports of rotation of the bearing spacers in AS350 tail rotor. Such rotation indicates that the inner bearing race may be rotating on its shaft. Rotation may cause excessive wear and cut the rotating plate, which will cause deterioration and loss of pitch control of the tail rotor.\n\nThe original issue of the directive addressed unsafe condition caused by the loss of pitch control of the tail rotor.\n\nThe original issue of this Airworthiness Directive became effective on 14 June 2000.\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 8 November 2004\n\n![](image.001.png)  \n\nThe above AD is notified in the Commonwealth of Australia Gazette on 1 December 2004.","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":5,"scope_assessment":{"changed":true,"description":"Amdt 1 revokes the original AD and reflects revision 1 of Eurocopter ASB 05.00.33 and DGAC AD F-2000-222-079; the amendment changes the effectivity list (which aircraft/parts are covered) but states the technical content is unchanged. The amendment also expressly accepts prior compliance with the original AD as an alternative (Background; Note 2)."},"complexity_factors":["Applicability conditions list several AS350 variants and exclude post‑Mod 076550 assemblies, so parts/aircraft status must be checked (Applicability).","Requirement is split into identification, daily monitoring, and conditional modification (1, 2.a, 2.b, 2.c) with different actions depending on alignment (Requirement).","Pilot-in-command may perform the daily inspection but must record a specific AD entry on the maintenance release and carry the directive aboard, adding operational record-keeping and carriage obligations (Requirement 2.a).","Multiple and differing compliance timeframes: within 10 flying hours, daily after last flight, by next 'T' basic inspection, or within 25 flying hours of detection (Compliance).","Mandatory embodiment of Mod 076550 is tied to findings and to procedures in an external Eurocopter Alert Service Bulletin (ASB 05.00.33 R1) and requires DGAC/EASA‑approved revisions, creating dependency on external documents and approvals (Requirement; Note 1).","The AD revokes and replaces a prior AD but allows compliance to the original AD as an acceptable alternative, creating an interaction between instruments (opening/Note 2/Background).","Technical risk is specific (bearing spacer rotation, inner race rotation, wear and cutting of rotating plate leading to loss of pitch control) but relies on inspection-derived detection rather than continuous monitoring (Background)."],"plain_english_summary":"This Airworthiness Directive requires operators of Eurocopter AS350 (Ecureuil) variants without Mod 076550 to identify and then daily monitor the alignment of the tail-rotor pitch-change plate spacer, and to embody Mod 076550 where instructed. It affects owners, pilots and maintenance organisations who must perform inspections, keep a maintenance-certification entry (pilots may perform the daily check) and carry the directive aboard to prevent spacer rotation that can wear or cut the rotating plate and lead to loss of tail-rotor pitch control."},"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This is an amendment to an existing Airworthiness Directive. The background explicitly states this amendment only reflects changes to the 'effectivity list' (which aircraft are affected) with no difference in technical contents. The scope remains tightly focused on the original safety issue: preventing tail rotor pitch control failure due to bearing spacer rotation."},"complexity_factors":["Multiple cross-references to external technical documents (Eurocopter ASB 05.00.33 R1, DGAC/EASA directives) without reproducing their contents","Conditional logic requiring different actions based on inspection outcomes (aligned vs misaligned paint marks)","Specific applicability exclusions (post-mod 076550 part number 350A33-2030-00)","Multiple compliance timelines (10 flying hours, daily, next 'T' inspection, 25 flying hours from detection)","Administrative note about acceptable alternate compliance with original AD version"],"plain_english_summary":"This CASA safety order targets Eurocopter AS350 (Ecureuil/Squirrel) helicopters without a specific factory tail-rotor modification. A tail-rotor bearing spacer can rotate and rub a nearby plate, risking loss of tail control and catastrophic rotor failure. Operators must identify affected components within 10 flying hours, pilots perform daily paint‑mark alignment checks (recorded in the maintenance log and carry the directive), and install the mandated modification either at the next T inspection if aligned or within 25 flying hours if misaligned."}},"importantCases":[],"_links":{"self":"/api/acts/ad-ecureuil-61-amdt-1-tr-head-pitch-change-plate-bearing-spacer","history":"/api/acts/ad-ecureuil-61-amdt-1-tr-head-pitch-change-plate-bearing-spacer/history","analysis":"/api/acts/ad-ecureuil-61-amdt-1-tr-head-pitch-change-plate-bearing-spacer/analysis","conflicts":"/api/acts/ad-ecureuil-61-amdt-1-tr-head-pitch-change-plate-bearing-spacer/conflicts","importantCases":"/api/acts/ad-ecureuil-61-amdt-1-tr-head-pitch-change-plate-bearing-spacer/important-cases","documents":"/api/acts/ad-ecureuil-61-amdt-1-tr-head-pitch-change-plate-bearing-spacer/documents"}}