{"id":"F2006B10612","name":"AD/HU 269/50 Amdt 1 - Main Rotor Mast and Tailboom Supports - Inspection and Modification","slug":"ad-hu-269-50-amdt-1-main-rotor-mast-and-tailboom-supports-inspection-and-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":116487,"registerId":"commonwealth-F2006B10612-current","compilationNumber":null,"startDate":"2026-04-03","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/HU 269/50 Amdt 1 - Main Rotor Mast and Tailboom Supports - Inspection and Modification","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 269/50\n\nAmdt 1\n\n\nMain Rotor Mast and Tailboom Supports - Inspection and Modification\n\n\n2/76\n\n \n\nApplicability: All models which have achieved 300 hours or more time in service. Document: Hughes SIN No. N-124.1.\n\nCompliance: For Part I: Unless already accomplished, within 100 hours time in service after 27 February 1976.\n\n \n\nFor Part II: With 300 hours time in service after 27 February 1976.\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\n \n\n \n\n \n","sortOrder":0}],"analysis":{"kimi_summary":{"_metrics":{"model":"kimi-k2.5","source":"moonshot-batch","completionTokens":2863},"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"As Amendment 1 to AD/HU 269/50, this appears to maintain the original scope focused on main rotor mast and tailboom support safety, likely adjusting compliance dates or applicability rather than expanding into new regulatory areas."},"complexity_factors":["Incorporation by reference to external technical document (Hughes SIN N-124.1) rather than spelling out requirements","Specific applicability threshold (300 hours time in service)","Two-part compliance schedule with different deadlines and conditions","Vintage 1976 legislative format with minimal definitional scaffolding"],"plain_english_summary":"**What this is:** An Airworthiness Directive (safety regulation) requiring specific safety work on Schweizer (Hughes) 269 Series helicopters.\n\n**Who it affects:** Owners and operators of these helicopters that have flown **300 hours or more** (\"time in service\" means flight hours).\n\n**What must be done:**\n*   **Inspection and modification** of the **main rotor mast** and **tailboom supports** (critical structural components).\n*   The exact technical steps aren't written in this document; instead, you must follow the manufacturer's instructions in **Hughes Service Information Notice No. N-124.1** (this is called \"incorporation by reference\").\n\n**When it must be done:**\n*   **Part I:** Within 100 flight hours after 27 February 1976 (unless already done).\n*   **Part II:** By the time the aircraft reaches 300 flight hours after 27 February 1976.\n\n**Why it matters:** This prevents structural failures in flight-critical components that could lead to catastrophic accidents."}},"importantCases":[],"_links":{"self":"/api/acts/ad-hu-269-50-amdt-1-main-rotor-mast-and-tailboom-supports-inspection-and-modification","history":"/api/acts/ad-hu-269-50-amdt-1-main-rotor-mast-and-tailboom-supports-inspection-and-modification/history","analysis":"/api/acts/ad-hu-269-50-amdt-1-main-rotor-mast-and-tailboom-supports-inspection-and-modification/analysis","conflicts":"/api/acts/ad-hu-269-50-amdt-1-main-rotor-mast-and-tailboom-supports-inspection-and-modification/conflicts","importantCases":"/api/acts/ad-hu-269-50-amdt-1-main-rotor-mast-and-tailboom-supports-inspection-and-modification/important-cases","documents":"/api/acts/ad-hu-269-50-amdt-1-main-rotor-mast-and-tailboom-supports-inspection-and-modification/documents"}}