{"id":"F2006B10588","name":"AD/HU 269/12 - Main Rotor Blade Flapping Hinge - Inspection","slug":"ad-hu-269-12-main-rotor-blade-flapping-hinge-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":116439,"registerId":"commonwealth-F2006B10588-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/HU 269/12 - Main Rotor Blade Flapping Hinge - Inspection","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 269/12 Main Rotor Blade Flapping Hinge - Inspection 12/64\n\nApplicability: Models 269A and 269B.\n\n \n\nDocument: 1. Hughes SINs 2A-391, 2A-1, -06.1 or 2B-07.1 where applicable; or\n\n \n\n2. Hughes SIN N-47.\n\n \n\nCompliance: At intervals not exceeding 400 hours time in service after 9 December 1964.\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\n \n\n \n","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The supplied directive sets a clear, narrow scope: it applies to Model 269A and 269B helicopters and requires inspections per specified Hughes SINs at intervals not exceeding 400 hours time in service after 9 December 1964. The document as provided does not indicate any change from a prior scope or any amendment; it only states the current applicability and compliance interval."},"complexity_factors":["Narrow applicability: limited to Hughes/Schweizer Model 269A and 269B (Applicability).","Fixed, recurring compliance interval: inspections required no less frequently than every 400 hours time in service after the baseline date (Compliance).","Cross-reference to external technical documents (Hughes SINs) rather than containing detailed procedures in-line, requiring operators to obtain and interpret those documents (Document).","Regulatory mandatory nature: compliance is required under Part 39 airworthiness directives, so failure to comply has regulatory consequences (header/title).","Date baseline specified (9 December 1964) which creates a historical compliance reference that operators must interpret relative to aircraft time-in-service records (Compliance)."],"plain_english_summary":"This directive mandates recurring inspections of the main rotor blade flapping hinge on Hughes/Schweizer Model 269A and 269B helicopters, at intervals not exceeding 400 flight hours measured from the baseline date.  \n\nOwners/operators must arrange and pay for inspections, repairs, and follow the referenced Hughes structural inspection notices (SINs) for procedures, creating an ongoing scheduling, administrative and compliance cost while delegating detailed inspection methods to the manufacturer documents."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, single-issue safety directive focused specifically on rotor blade hinge inspection for two specific helicopter models. It has not expanded beyond its original narrow technical purpose."},"complexity_factors":["Very short document (approximately 150 words)","Only 2 defined applicability criteria (Models 269A and 269B)","Single compliance requirement with clear time interval (400 hours)","No nested exceptions or conditional logic","Simple cross-reference to manufacturer documents (SINs) rather than legislative provisions","No interpretation section or defined terms within the instrument itself"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** — essentially a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA). It requires owners and operators of specific **Schweizer (formerly Hughes) 269A and 269B helicopters** to inspect the **main rotor blade flapping hinge** at regular intervals.\n\n**What it does:**\n- Mandates inspection of a critical helicopter component (the flapping hinge allows rotor blades to move up and down during flight, which is essential for stable flight)\n- Requires this inspection every **400 hours of flight time** (\"time in service\")\n- The requirement took effect from **9 December 1964**\n\n**Who it affects:**\n- Owners and operators of Hughes/Schweizer 269A and 269B helicopter models\n- Maintenance engineers responsible for keeping these aircraft airworthy\n\n**Why it matters:**\nThe flapping hinge is a vital part of helicopter flight mechanics. If it fails, the rotor system could malfunction with catastrophic consequences. This AD ensures potential defects are caught before they cause accidents. The reference to specific Service Information Notices (SINs) means inspectors must follow manufacturer guidelines when conducting these checks.\n\n**Key terms explained:**\n- **Airworthiness Directive (AD):** A legally enforceable safety notice that must be complied with to keep an aircraft certified to fly\n- **Time in service:** Actual flight hours (not just calendar time or engine running time)\n- **SIN (Service Information Notice):** Manufacturer-issued technical bulletins with maintenance instructions"}},"importantCases":[],"_links":{"self":"/api/acts/ad-hu-269-12-main-rotor-blade-flapping-hinge-inspection","history":"/api/acts/ad-hu-269-12-main-rotor-blade-flapping-hinge-inspection/history","analysis":"/api/acts/ad-hu-269-12-main-rotor-blade-flapping-hinge-inspection/analysis","conflicts":"/api/acts/ad-hu-269-12-main-rotor-blade-flapping-hinge-inspection/conflicts","importantCases":"/api/acts/ad-hu-269-12-main-rotor-blade-flapping-hinge-inspection/important-cases","documents":"/api/acts/ad-hu-269-12-main-rotor-blade-flapping-hinge-inspection/documents"}}