{"id":"F2006B10640","name":"AD/HU 269/81 - Main Transmission Assembly","slug":"ad-hu-269-81-main-transmission-assembly","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":116544,"registerId":"commonwealth-F2006B10640-current","compilationNumber":null,"startDate":"2026-04-03","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/HU 269/81 - Main Transmission Assembly","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)  Schweizer (Hughes) 269 Series Helicopters\n\n \n\nAD/HU 269/81 Main Transmission Assembly 6/86\n\nApplicability: All Model 269A, 269B and 269C Helicopters fitted with main transmission P/No. 269A5175-11, -13, -15 and -17 equipped with P/No. 269A5103-21 or -31 pinion assembly.\n\n \n\nRequirement: Action in accordance with Schweizer Service Information No. N195. Compliance: 1. At the next 300 or 400 hour inspection after 30 June 1986.\n\n2. For spares, prior to installation in an aircraft.\n\n \n\nBackground: A wrong lock washer may have been used on assembly of a number of main transmission assemblies upper pulley nut. This may lead to loss of torque on the aft pinion nut and possible premature wear of the input pinion shaft.\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":2890},"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This amendment (6/86) maintains the original 1981 directive's scope focused on the main transmission assembly lock washer defect. The scope remains limited to specific helicopter models and the identified mechanical issue without expansion into unrelated systems."},"complexity_factors":["Single-issue directive with straightforward mechanical scope","Only two compliance pathways (in-service aircraft vs spare parts)","Heavy reliance on external technical reference (Schweizer Service Information No. N195) without reproducing its content","Specific part number identification required for applicability (4 transmission part numbers and 2 pinion assembly numbers)"],"plain_english_summary":"This AD requires owners of certain Schweizer (Hughes) 269A/B/C helicopters with specified transmission parts to inspect and correct a potentially incorrect lock washer on the main transmission upper pulley nut per Service Information No. N195. Inspections must be done at the next scheduled maintenance after 30 June 1986 (or before installing affected spare parts). The action prevents loss of pinion nut torque and premature input pinion shaft wear, protecting transmission safety."}},"importantCases":[],"_links":{"self":"/api/acts/ad-hu-269-81-main-transmission-assembly","history":"/api/acts/ad-hu-269-81-main-transmission-assembly/history","analysis":"/api/acts/ad-hu-269-81-main-transmission-assembly/analysis","conflicts":"/api/acts/ad-hu-269-81-main-transmission-assembly/conflicts","importantCases":"/api/acts/ad-hu-269-81-main-transmission-assembly/important-cases","documents":"/api/acts/ad-hu-269-81-main-transmission-assembly/documents"}}