{"id":"F2006B10743","name":"AD/HU 369/79 - Tail Rotor Transmission Output Shaft Duplex Bearings","slug":"ad-hu-369-79-tail-rotor-transmission-output-shaft-duplex-bearings","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":116747,"registerId":"commonwealth-F2006B10743-current","compilationNumber":null,"startDate":"2026-04-03","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/HU 369/79 - Tail Rotor Transmission Output Shaft Duplex Bearings","content":"---\nmeta-content-style-type: text/css\nmeta-content-type: application/xhtml+xml; charset=utf-8\nmeta-generator: Aspose.Words for .NET 22.10.0\n---\n\n?xml version=\"1.0\" encoding=\"utf-8\" standalone=\"no\"?>\n\nCOMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n \n\n![](image.001.png)  McDonnell Douglas (Hughes) and Kawasaki 369 Series Helicopters\n\n \n\nAD/HU 369/79 Tail Rotor Transmission Output Shaft Duplex Bearings\n\n\n13/89\n\n \n\nApplicability: All model 369D, 369E and 369F/FF series helicopters with P/N 369D25400 tail rotor assemblies installed.\n\n \n\nRequirement: Action in accordance with McDonnell Douglas S.I.N No DN-161, EN-51 or FN-38, as applicable.\n\n \n\nCompliance: At the next periodic inspection for issue of a Maintenance Release or by 30 June 1990, whichever occurs first.\n\n \n\nBackground: Duplex bearings fitted to the tail rotor gearbox output shaft may have been manufactured with excessive tolerances. To confirm the bearing tolerance is within limits a one time inspection for excessive play in the output shaft, is required.\n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n","sortOrder":0}],"analysis":{"kimi_summary":{"_metrics":{"model":"kimi-k2.5","source":"moonshot-batch","completionTokens":2006},"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"The directive maintains its original narrow scope: a one-time inspection requirement for specific bearings on specific helicopter models due to manufacturing tolerance concerns. No expansion of coverage or purpose is evident."},"complexity_factors":["Requires cross-referencing external manufacturer service instructions (S.I.N. numbers) not reproduced in the directive text","Technical aviation terminology (duplex bearings, output shaft, tail rotor assemblies, Maintenance Release)","Specific part number applicability filtering (P/N 369D25400)","Dual-trigger compliance deadline (periodic inspection-based OR date-based, whichever occurs first)"],"plain_english_summary":"This CASA safety directive requires operators of McDonnell Douglas (Hughes) and Kawasaki 369 series helicopters fitted with tail rotor part 369D25400 to perform a one‑time inspection for excessive play in the tail‑rotor gearbox output shaft. It addresses potentially loose duplex bearings that could compromise flight safety and must be done per the applicable manufacturer service instruction by the next maintenance‑release inspection or by 30 June 1990, whichever is earlier."}},"importantCases":[],"_links":{"self":"/api/acts/ad-hu-369-79-tail-rotor-transmission-output-shaft-duplex-bearings","history":"/api/acts/ad-hu-369-79-tail-rotor-transmission-output-shaft-duplex-bearings/history","analysis":"/api/acts/ad-hu-369-79-tail-rotor-transmission-output-shaft-duplex-bearings/analysis","conflicts":"/api/acts/ad-hu-369-79-tail-rotor-transmission-output-shaft-duplex-bearings/conflicts","importantCases":"/api/acts/ad-hu-369-79-tail-rotor-transmission-output-shaft-duplex-bearings/important-cases","documents":"/api/acts/ad-hu-369-79-tail-rotor-transmission-output-shaft-duplex-bearings/documents"}}