{"id":"F2009L00830","name":"AD/ECUREUIL/134 Amdt 1 - Starter-generator Damping Assembly","slug":"ad-ecureuil-134-amdt-1-starter-generator-damping-assembly","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":77990,"registerId":"commonwealth-F2009L00830-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Eurocopter AS 350 (Ecureuil) Series Heli","sectionType":"division","heading":"Eurocopter AS 350 (Ecureuil) Series Helicopters","content":"### Eurocopter AS 350 (Ecureuil) Series Helicopters\n\n| AD/ECUREUIL/134 Amdt 1 | Starter-generator Damping Assembly | 5/2009 DM |\n| ---------------------- | ---------------------------------- | --------- |\n\n| Applicability: | EUROCOPTER AS 350 B, BA, BB, B1, B2, B3 and EC 130 B4 helicopters, all serial numbers, if equipped with ARRIEL engines where Aircraft Parts Corporation (APC) starter-generators with Part Number (P/N) 150SG122Q or P/N 200SGL130Q without “004” marking on their name plates are installed.                                                                                                                                                                                                                                                                                                                                                |\n| -------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | 1. Adjust and mark the APC starter-generator in accordance with the instructions of paragraph 2.B.2 of EUROCOPTER AS350 Alert Service Bulletin (ASB) No. 80.00.07 Revision 1 or EC130 ASB No. 80A003 Revision 1, as applicable to the helicopter version.2. Do not install on a helicopter a starter-generator with P/N affected by this AD unless it has been adjusted and marked as required in the relevant ASB.The use of later revisions of the documents listed in this AD is acceptable for compliance with the requirements of this AD.Note: EASA AD 2009-0027 dated 18 February 2009 refers. This AD supersedes EASA AD 2009-0004.  |\n| Compliance:    | For Requirement 1 - Within 110 flight hours or 3 months, whichever occurs first after the effective date of this AD, unless previously accomplished.For Requirement 2 - After the effective date of this AD.                                                                                                                                                                                                                                                                                                                                                                                                                                 |\n|                | This Amendment becomes effective on 12 March 2009.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                           |\n| Background:    | EUROCOPTER has received reports of engine flame-outs in operation. In all cases of engine flame-out there was a failure of the 41-tooth pinion in the engine accessory gear box.All the concerned helicopters were equipped with starter-generators manufactured by the APC company (currently UNISON). In each case, it was found that the torque damping system of the starter-generator was inoperative.Further investigations have been conducted to assess the efficiency of the 150SG and 200SGL-type generator damping systems, which have revealed that the failure of the torque damping system was due to an incorrect adjustment. |\n\n|     | If the damping system is incorrectly adjusted, torque oscillations may not be limited and can induce bending stress on the 41-tooth pinion of the accessory gear box, contributing to the pinion failure. Such pinion failure causes the fuel pump to stop which results in an engine flame-out.Pending additional investigations, this AD required an inspection of the alignment and torque of the APC starter-generator damping assembly and, in case of discrepancies, the accomplishment of corrective actions.This amendment supersedes the original requirements of this AD, and now requires a new adjustment procedure which has proven to be more reliable and optimizes the performance of the APC starter-generator assembly. |\n| --- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n\n![](image.001.png)  \nJames Coyne  \nDelegate of the Civil Aviation Safety Authority\n\n2 March 2009","sortOrder":0},{"sectionNumber":"AD/ECUREUIL/134 Amdt 1","sectionType":"part","heading":"AD/ECUREUIL/134 Amdt 1","content":"## AD/ECUREUIL/134 Amdt 1","sortOrder":1},{"sectionNumber":"Starter-generator Damping Assembly","sectionType":"part","heading":"Starter-generator Damping Assembly","content":"## Starter-generator Damping Assembly","sortOrder":2},{"sectionNumber":"5/2009 DM","sectionType":"part","heading":"5/2009 DM","content":"## 5/2009 DM","sortOrder":3}],"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 supersedes the original AD and replaces the prior inspection/alignment requirement with a new adjustment procedure for the APC starter-generator damping assembly. The change narrows compliance to performing the revised adjustment and marking (per EUROCOPTER ASB paragraph 2.B.2) and prohibits installing unadjusted units until the new procedure is completed (Background/Requirement)."},"complexity_factors":["Targeted technical scope: specific helicopter models (AS350 B/BA/BB/B1/B2/B3 and EC130 B4) and precise APC starter-generator part numbers, plus absence of a “004” nameplate mark (Applicability).","Single principal action with installation prohibition: requires adjustment and marking per EUROCOPTER ASB paragraph 2.B.2 and forbids installing affected units until adjusted (Requirement).","Fixed compliance window: remedial work must be done within 110 flight hours or 3 months, whichever occurs first (Compliance).","Cross-reference to external service documents: compliance depends on following a particular Alert Service Bulletin (ASB) procedure; later ASB revisions are accepted (Requirement).","Regulatory linkage and update history: the AD supersedes an earlier AD and cites an EASA AD, creating dependence on prior regulatory instruments (Note/Background).","Operational/administrative impacts: maintenance scheduling, parts inventory control (tracking which units bear the mark), and shop capability to perform the specific adjustment increase compliance tasks (Background/Requirement).","Enforcement and allocation of cost/responsibility: owners/operators must act and bear costs; CASA (via its delegate) enforces the prohibition and effective date (Compliance/Signature)."],"plain_english_summary":"*This airworthiness directive requires adjustment and marking of specific APC starter-generators (P/N 150SG122Q or 200SGL130Q without a “004” nameplate) on Eurocopter AS350 and EC130 helicopters, and prohibits installing those units until adjusted.* It responds to incorrect torque-damper adjustment that can lead to accessory‑gear pinion failure and engine flame‑out. Owners/operators must carry out the adjustment within 110 flight hours or 3 months and bear the compliance cost; the Civil Aviation Safety Authority enforces the installation prohibition."},"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This is an amendment to an existing Airworthiness Directive, but it remains tightly focused on its original purpose: addressing the specific mechanical failure mode in APC starter-generator damping assemblies. The amendment updates the technical procedure to a more reliable method but does not expand the scope beyond the original safety issue (preventing engine flame-outs due to pinion failure). The applicability criteria remain essentially the same as the original AD."},"complexity_factors":["Highly specific technical applicability criteria involving multiple helicopter models, engine types, manufacturer part numbers, and physical markings ('004' marking exclusion)","Cross-references to external technical documents (Eurocopter Alert Service Bulletins) which are not reproduced in the directive itself","Dual compliance timelines (flight hours vs. calendar time) with an 'unless previously accomplished' exception","Nested conditional logic: applicability depends on model AND engine type AND specific part numbers AND absence of specific marking","Amendment structure that supersedes previous requirements and references superseded EASA directives (2009-0004 and 2009-0027)"],"plain_english_summary":"This AD requires owners/operators of certain Eurocopter AS350 and EC130 helicopters fitted with ARriel engines and APC starter‑generators (P/N 150SG122Q or 200SGL130Q) lacking a \"004\" nameplate mark to have the starter‑generator adjusted and marked per Eurocopter service bulletins within 110 flight hours or 3 months. It also bans installation of unadjusted units. The fix prevents vibration damage to a critical gear that can cause in‑flight engine flame‑out."}},"importantCases":[],"_links":{"self":"/api/acts/ad-ecureuil-134-amdt-1-starter-generator-damping-assembly","history":"/api/acts/ad-ecureuil-134-amdt-1-starter-generator-damping-assembly/history","analysis":"/api/acts/ad-ecureuil-134-amdt-1-starter-generator-damping-assembly/analysis","conflicts":"/api/acts/ad-ecureuil-134-amdt-1-starter-generator-damping-assembly/conflicts","importantCases":"/api/acts/ad-ecureuil-134-amdt-1-starter-generator-damping-assembly/important-cases","documents":"/api/acts/ad-ecureuil-134-amdt-1-starter-generator-damping-assembly/documents"}}