{"id":"F2006B09321","name":"AD/EC 135/7 Amdt 1 - Automatic Engine Control","slug":"ad-ec-135-7-amdt-1-automatic-engine-control","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":53465,"registerId":"commonwealth-F2006B09321-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/EC 135/7 Amdt 1 - Automatic Engine Control","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![](image.002.png)  \nEurocopter EC 135 Series Helicopters\n\nAIRWORTHINESS DIRECTIVE\n\n![](image.002.png)\n\n![](image.003.png)For the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/EC 135/7 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\nBackground: The German Luftfahrt-Bundesamt has advised that several instances have been reported of a FADEC FAIL caution indication being displayed for one engine. The caution display was caused by a parameter discrepancy, which was generated within the Fuel Main Metering Unit and transmitted to the FADEC. This discrepancy may lead to “freezing” of the Fuel Main Metering Valve at its momentary position, resulting in loss of the automatic engine control in the affected system.\n\n![](image.004.png)The original issue of this Directive introduced a synchronisation procedure that prevented the occurrence of the discrepancy between the parameters and thus sustained the automatic engine control.\n\nThis amendment limits the applicability to EC 135 T1 helicopters fitted with Arrius 2B1 engines and requires the installation of a new software version designed to prevent failure of the automatic engine control in those helicopters.\n\nCOMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n![](image.005.png)The original issue of this Directive became effective on 2 November 2001.\n\n![Signature of Eugene Paul Holzapfel, Delegate of the Civil Aviation Safety Authority.](image.006.png)  \n\nEugene Paul Holzapfel\n\nDelegate of the Civil Aviation Safety Authority 5 December 2001\n\n![](image.002.png)  \n\nThe above AD is notified in the Commonwealth of Australia Gazette on 9 January 2002.","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"The amendment narrows scope from the original, limiting applicability specifically to EC135 T1 helicopters with Arrius 2B1 engines and replaces the previously mandated synchronisation procedure with a required FADEC software version intended to prevent automatic engine control failure."},"complexity_factors":["Technical specificity: action is a targeted FADEC software update addressing a fuel metering parameter discrepancy.","Narrow applicability: limited to Eurocopter EC135 T1 helicopters with Arrius 2B1 engines.","Regulatory change: revokes and replaces a prior AD, altering the mandated corrective method (from a synchronisation procedure to a software install).","Operational impact: requires maintenance scheduling and aircraft downtime to install software.","Compliance burden falls on aircraft owners/operators to fund and execute the update per the AD."],"plain_english_summary":"This Airworthiness Directive revokes the prior AD and requires operators of Eurocopter EC135 T1 helicopters fitted with Arrius 2B1 engines to install a FADEC software update. The update is designed to stop a parameter discrepancy in the Fuel Main Metering Unit that can freeze the metering valve and display a FADEC FAIL, causing loss of automatic engine control.\n\nThe Civil Aviation Safety Authority’s delegate requires compliance; aircraft owners/operators must arrange and pay for the software installation within the AD’s compliance timeframe."},"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"},"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":true,"description":"The amendment significantly narrows scope compared to the original directive. The original AD applied more broadly to EC 135 series helicopters; this amendment limits applicability specifically to EC 135 T1 helicopters fitted with Arrius 2B1 engines. The technical solution also changed from a 'synchronisation procedure' to installation of new software."},"complexity_factors":["Single, clearly defined applicability (one helicopter model with specific engine type)","Straightforward amendment structure: revokes previous AD, replaces with narrowed scope","No nested conditional logic or extensive cross-referencing to other legislation","Clear, sequential sections: Background → Applicability → Requirement → Compliance","Technical aviation terminology present but explained in context (FADEC, Fuel Main Metering Unit)","Short document (approximately 300 words of substantive text)"],"plain_english_summary":"This AD replaces an earlier order and narrows requirements to EC135 T1 helicopters with Arrius 2B1 engines, mandating installation of updated engine-control software.  \n\nIt addresses FADEC FAIL events caused by a Fuel Main Metering Unit data mismatch that can freeze the fuel valve and disable automatic engine control. Affects owners, operators, and maintenance organisations; the software fix prevents the parameter mismatch and reduces risk of in-flight engine control loss."}},"importantCases":[],"_links":{"self":"/api/acts/ad-ec-135-7-amdt-1-automatic-engine-control","history":"/api/acts/ad-ec-135-7-amdt-1-automatic-engine-control/history","analysis":"/api/acts/ad-ec-135-7-amdt-1-automatic-engine-control/analysis","conflicts":"/api/acts/ad-ec-135-7-amdt-1-automatic-engine-control/conflicts","importantCases":"/api/acts/ad-ec-135-7-amdt-1-automatic-engine-control/important-cases","documents":"/api/acts/ad-ec-135-7-amdt-1-automatic-engine-control/documents"}}