{"id":"F2006B02471","name":"AD/AS 355/14 Amdt 1 - Combiner Gearbox R.H. and L.H.","slug":"ad-as-355-14-amdt-1-combiner-gearbox-r-h-and-l-h","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":41727,"registerId":"commonwealth-F2006B02471-current","compilationNumber":null,"startDate":"2026-04-01","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/AS 355/14 Amdt 1 - Combiner Gearbox R.H. and L.H.","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)  \nEurocopter AS 355 (Twin Ecureuil) Series Helicopters\n\nAD/AS 355/14\n\nAmdt 1\n\n  \nCombiner Gearbox R.H. and L.H. 5/88\n\nApplicability: All model AS355 aircraft fitted with input flanges P/No 355A32-2095-20 and 21 on which either modification AMS 350A07-9527 or AMS 350A07-9534 has not been embodied.\n\nRequirement: Action in accordance with Aerospatiale SB 05-09 Revision 2.\n\nCompliance: (a) For those aircraft whose main gearbox has completed 250 hours time in service or more; within the next 50 hours time in service after 19 May 1988 or by\n\n30 September 1988 whichever occurs first.\n\n    (b) For those aircraft whose main gearbox has completed less than 250 hours time in service; prior to exceeding 300 hours gearbox time in service.\n\n    (c) Thereafter, at intervals not exceeding 300 hours time in service.\n\nBackground: The manufacturer has reported several cases of deep wear found on the combiner gearbox input flanges due to contact between the engine coupling shaft and the input flanges. This directive has been amended to reflect Revision 1 of the Requirement Document.","sortOrder":0}],"analysis":{"kimi_summary":{"_metrics":{"model":"kimi-k2.5","source":"moonshot-batch","completionTokens":2005},"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This amendment updates the technical reference from the original Service Bulletin to Revision 2, reflecting updated manufacturer guidance. It does not expand the scope beyond the original purpose of addressing wear on specific combiner gearbox input flanges."},"complexity_factors":["Conditional compliance deadlines based on aircraft flight hours (three separate timing pathways)","Reference to external technical document (Aerospatiale Service Bulletin 05-09 Revision 2) without reproducing its contents","Technical aviation part numbers (P/No 355A32-2095-20/21) and modification identifiers (AMS 350A07-9527)","Amendment context requiring comparison with previous version to understand full current requirements"],"plain_english_summary":"This mandatory safety rule requires owners of Eurocopter AS 355 (Twin Ecureuil) helicopters fitted with specified combiner gearbox input flanges to inspect and, if necessary, replace worn parts per Aerospatiale Service Bulletin 05-09 Rev.2. Owners with exemptions from AMS 350A07-9527 or -9534 are not affected.\n\nInspections must be done promptly (high-hour gearboxes within 50 flight hours or by 30 Sep 1988; low-hour before 300 total hours) and repeated at least every 300 hours to prevent gearbox failure and loss of rotor power."}},"importantCases":[],"_links":{"self":"/api/acts/ad-as-355-14-amdt-1-combiner-gearbox-r-h-and-l-h","history":"/api/acts/ad-as-355-14-amdt-1-combiner-gearbox-r-h-and-l-h/history","analysis":"/api/acts/ad-as-355-14-amdt-1-combiner-gearbox-r-h-and-l-h/analysis","conflicts":"/api/acts/ad-as-355-14-amdt-1-combiner-gearbox-r-h-and-l-h/conflicts","importantCases":"/api/acts/ad-as-355-14-amdt-1-combiner-gearbox-r-h-and-l-h/important-cases","documents":"/api/acts/ad-as-355-14-amdt-1-combiner-gearbox-r-h-and-l-h/documents"}}