{"id":"F2008L03745","name":"AD/EC 225/10 - Rotor Flight Controls - Tail Servo-control","slug":"ad-ec-225-10-rotor-flight-controls-tail-servo-control","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":75495,"registerId":"commonwealth-F2008L03745-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Eurocopter EC 225 Series Helicopters","sectionType":"division","heading":"Eurocopter EC 225 Series Helicopters","content":"### Eurocopter EC 225 Series Helicopters\n\n| AD/EC 225/10 | Rotor Flight Controls - Tail Servo-control | 11/2008 |\n| ------------ | ------------------------------------------ | ------- |\n\n| Applicability: | Eurocopter EC 225LP helicopters fitted with tail servo-control P/N SC7252 before amendment A.                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |\n| -------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | 1. Apply the tightening torque in specified in paragraph 2.B.2. of EUROCOPTER EC 225 Alert Service Bulletin (ASB) No. 67A001 or later NAA approved revision.2. Manually check for absence of axial play of the two control levers along the distributor shafts of the tail servo-control, in accordance with paragraph 2.B.3. of ASB No. 67A001 or later NAA approved revision.3. In case of play, replace the servo-control in accordance with paragraph 2.B.3. of the ASB 67A001 or later NAA approved revision.Note: DGAC AD F-2005-138 dated 3 August 2005 refers. |\n| Compliance:    | For Requirement 1 - No later than within 110 flying hours after the effective date of this AD.For Tail Servo Controls held as spares - Before installation on a helicopter.For Requirement 2 - No later than within a period of 135 to 165 flying hours following completion of Requirement 1 of this AD.For Requirement 3 - Before further flight.                                                                                                                                                                                                                    |\n|                | This Airworthiness Directive becomes effective on 23 October 2008.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     |\n| Background:    | This AD is in response to a case of control lever slipping along the shaft of one of the distributors, discovered upon removal of a tail servo-control for repair on an AS 332 helicopter.The control lever could have totally separated from the distributor shaft, which could lead to the loss of the tail rotor control.The attaching principle of the control lever/shaft connection of tail servo-control distributors on AS 332 and EC 225 is identical.                                                                                                        |\n\n|     | Consequently, the purpose of this AD is to eliminate the risk of disconnection of tail servo-control distributor control levers. |\n| --- | -------------------------------------------------------------------------------------------------------------------------------- |\n\n![](image.001.png)  \nCharles Lenarcic  \nDelegate of the Civil Aviation Safety Authority\n\n8 September 2008","sortOrder":0},{"sectionNumber":"AD/EC 225/10","sectionType":"part","heading":"AD/EC 225/10","content":"## AD/EC 225/10","sortOrder":1},{"sectionNumber":"Rotor Flight Controls - Tail Servo-contr","sectionType":"part","heading":"Rotor Flight Controls - Tail Servo-control","content":"## Rotor Flight Controls - Tail Servo-control","sortOrder":2},{"sectionNumber":"11/2008","sectionType":"part","heading":"11/2008","content":"## 11/2008","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":4,"scope_assessment":{"changed":false,"description":"The AD confines action to EC 225LP helicopters fitted with a specific tail servo‑control part number (P/N SC7252 before amendment A) and to spares before installation. The instrument implements targeted inspection, torque and replacement measures to eliminate the risk of control‑lever disconnection described in the Background; it does not expand to other models or parts beyond that stated Applicability."},"complexity_factors":["Technical maintenance actions required: precise torque application and manual axial‑play check; replacement if play is found (Requirement 1–3).","Multiple, staggered compliance windows creating scheduling complexity: 110 flight hours, 135–165 flight hours after initial task, spares-before-installation, and immediate grounding if play found (Compliance).","Part‑number and configuration limited applicability (EC 225LP with tail servo-control P/N SC7252 before amendment A), requiring owner/operator traceability of component history (Applicability).","Normative reference to EUROCOPTER ASB No. 67A001 or later NAA‑approved revision introduces regulatory dependency and possible variation over time (Requirement).","Immediate operational impact where play is detected — replacement required before further flight — which can disrupt service and increase downtime (Requirement 3; Compliance).","Costs fall to operators/owners and maintenance organisations for inspections, torque work, part replacement and potential aircraft downtime (Compliance; Requirement).","Risk management focus is narrow and component‑specific (tail servo distributor control levers), limiting scope but concentrating consequences on affected aircraft (Background; Applicability).","Implementation requires maintainer competence and recordkeeping to show ASB compliance and that spares are inspected before installation (Requirement; Compliance)."],"plain_english_summary":"This Airworthiness Directive requires operators of Eurocopter EC 225LP helicopters fitted with tail servo-control P/N SC7252 (pre‑amendment A) to apply a specified tightening torque, manually check for axial play of two control levers, and replace the servo if play is detected, following EUROCOPTER ASB No. 67A001 (or later NAA‑approved revision). Compliance deadlines differ by task (in‑service hours, spares-before-installation, and ‘before further flight’ if play is found), so operators and owners must inspect, maintain or replace affected parts."},"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This is a targeted safety directive addressing a specific mechanical defect in a specific helicopter model. The scope remains precisely limited to the tail servo-control issue identified in the background. There is no evidence of scope creep; it does not expand to other aircraft systems or models beyond the EC 225LP (and the referenced AS 332 in the background for context only)."},"complexity_factors":["Short, single-purpose directive with only 3 requirements","Clear sequential compliance timeline (110 hours, then 135-165 hours after)","Single defined part number (SC7252) and single helicopter model (EC 225LP)","References external technical document (Eurocopter ASB No. 67A001) but does not reproduce its content","Simple conditional logic: only Requirement 3 triggers if play is detected in Requirement 2","No nested definitions, no cross-references to other legislation, no exceptions to exceptions"],"plain_english_summary":"This CASA Airworthiness Directive requires owners/operators of Eurocopter EC225LP helicopters fitted with tail servo-control P/N SC7252 (unless modified to Amendment A) to inspect and, if necessary, replace the unit. It responds to reports that an internal control lever can slip or detach, risking loss of tail-rotor directional control.\n\nActions include torquing a bolt within 110 flight hours, a manual play check at 135–165 hours, replacing any servo with detected play before flight, and ensuring spares are corrected before installation."}},"importantCases":[],"_links":{"self":"/api/acts/ad-ec-225-10-rotor-flight-controls-tail-servo-control","history":"/api/acts/ad-ec-225-10-rotor-flight-controls-tail-servo-control/history","analysis":"/api/acts/ad-ec-225-10-rotor-flight-controls-tail-servo-control/analysis","conflicts":"/api/acts/ad-ec-225-10-rotor-flight-controls-tail-servo-control/conflicts","importantCases":"/api/acts/ad-ec-225-10-rotor-flight-controls-tail-servo-control/important-cases","documents":"/api/acts/ad-ec-225-10-rotor-flight-controls-tail-servo-control/documents"}}