{"id":"F2006B10703","name":"AD/HU 369/41 Amdt 10 - Main Rotor Blade Root Fitting Assembly and Hub Lead-Lag Link Assemblies","slug":"ad-hu-369-41-amdt-10-main-rotor-blade-root-fitting-assembly-and-hub-lead-lag-link-assemblies","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":116669,"registerId":"commonwealth-F2006B10703-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"AIRWORTHINESS DIRECTIVE","sectionType":"part","heading":"AIRWORTHINESS DIRECTIVE","content":"# AIRWORTHINESS DIRECTIVE\n\n![](image.002.png)\n\n![](image.002.png)  \nFor the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/HU 369/41 Amdt 9 and issues the following AD under subregulation 39.1 (1) of CAR 1998. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.","sortOrder":0},{"sectionNumber":"AD/HU 369/41","sectionType":"part","heading":"AD/HU 369/41","content":"# AD/HU 369/41\n\nAmdt 10\n\n  \n\nMain Rotor Blade Root Fitting Assembly and Hub Lead-Lag Link Assemblies\n\n  \n7/2000","sortOrder":1},{"sectionNumber":"DM","sectionType":"part","heading":"DM","content":"# AD/HU 369/41\n\nAmdt 10\n\n  \n\nMain Rotor Blade Root Fitting Assembly and Hub Lead-Lag Link Assemblies\n\n  \n7/2000\n\n# DM","sortOrder":2}],"analysis":{"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":true,"description":"The instrument explicitly revokes Airworthiness Directive AD/HU 369/41 Amdt 9 and issues AD/HU 369/41 Amdt 10, so the regulatory instrument has been replaced. The supplied excerpt does not include the Requirement, Applicability or Compliance content that would show how the substantive scope (which parts, which aircraft, what actions, and timing) has been altered, so the assessment is limited to noting that the applicable AD version has changed and that operators must follow Amdt 10 rather than Amdt 9 (revocation and re‑issue language; Requirement/Applicability/Compliance sections referenced)."},"complexity_factors":["Technical subject matter: main rotor blade root fitting assemblies and hub lead–lag link assemblies (aviation structural and component issues).","Delegated regulatory power: issuance under subregulation 39.1(1) of CAR 1998 gives CASA delegate discretion to set required corrective actions.","Document structure dependence: key obligations and effects are contained in Requirement, Applicability and Compliance sections which are not included here, requiring cross‑reference to fully understand duties.","Change management: revocation of a prior amendment (Amdt 9) and replacement by Amdt 10 requires operators to track versioning and ensure they comply with the current AD.","Operational and cost uncertainty: compliance implies possible inspections/repairs/downtime but the excerpt lacks specifics, complicating impact assessment."],"plain_english_summary":"This instrument revokes AD/HU 369/41 Amendment 9 and replaces it with Amendment 10 addressing main rotor blade root fitting assemblies and hub lead–lag link assemblies. Issued by a CASA delegate under subreg 39.1(1) CAR 1998, it requires owners/operators of the listed aircraft to carry out the actions and timings specified in the AD’s Requirement and Compliance sections to correct an identified unsafe condition. Practical effect: affected operators must plan, fund and complete the mandated work to remain compliant."},"kimi_summary":{"content_quality":"ok","complexity_score":4,"scope_assessment":{"changed":false,"description":"This appears to be a routine amendment (Amdt 10) to an existing Airworthiness Directive. The scope remains focused on the specific helicopter components (main rotor blade root fittings and hub lead-lag link assemblies) as indicated by the consistent title across amendments. Without the full text of previous amendments, there is no evidence of scope creep beyond the original safety purpose."},"complexity_factors":["Multiple cross-references to other document sections (applicability, requirement, compliance, background) that are not fully reproduced in this excerpt","Regulatory framework requires understanding of CAR 1998 (Civil Aviation Regulations) and subregulation 39.1(1)","Technical aviation terminology (\"lead-lag link assemblies\", \"blade root fitting\") assumes specialised knowledge","Amendment structure creates version control complexity — revokes Amdt 9, issues Amdt 10","Conditional compliance structure (circumstances, instructions, timing) creates layered obligations","Document appears to be an excerpt or cover page — full directive would contain detailed technical specifications, serial number ranges, and compliance timelines not shown here"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** — a mandatory safety order issued by the Civil Aviation Safety Authority (CASA) that requires specific maintenance actions on certain helicopter parts.\n\n**What it does:**\n- **Revokes** the previous version (Amendment 9) of this directive\n- **Issues a new, updated version** (Amendment 10) under aviation safety regulations\n- Requires owners/operators to take specific safety actions on **main rotor blade root fittings** and **hub lead-lag link assemblies** on certain helicopters\n\n**Who it affects:**\n- Owners and operators of specific **Hughes 369/MD 500 series helicopters** (indicated by \"HU 369\" in the reference number)\n- Maintenance organisations servicing these aircraft\n\n**Why it matters:**\nThese helicopter components are critical to flight safety. The \"lead-lag\" links allow rotor blades to move slightly back and forth during rotation, while blade root fittings attach the blades to the hub. Failures in these parts can cause catastrophic rotor system failure. This AD mandates inspection or replacement to address an identified **unsafe condition**.\n\n**What must happen:**\n- The required actions must be performed:\n  - In the specified circumstances\n  - Following the exact instructions in the requirement section\n  - By the deadline in the compliance section\n\nFailure to comply makes the aircraft unairworthy — it cannot legally fly."}},"importantCases":[],"_links":{"self":"/api/acts/ad-hu-369-41-amdt-10-main-rotor-blade-root-fitting-assembly-and-hub-lead-lag-link-assemblies","history":"/api/acts/ad-hu-369-41-amdt-10-main-rotor-blade-root-fitting-assembly-and-hub-lead-lag-link-assemblies/history","analysis":"/api/acts/ad-hu-369-41-amdt-10-main-rotor-blade-root-fitting-assembly-and-hub-lead-lag-link-assemblies/analysis","conflicts":"/api/acts/ad-hu-369-41-amdt-10-main-rotor-blade-root-fitting-assembly-and-hub-lead-lag-link-assemblies/conflicts","importantCases":"/api/acts/ad-hu-369-41-amdt-10-main-rotor-blade-root-fitting-assembly-and-hub-lead-lag-link-assemblies/important-cases","documents":"/api/acts/ad-hu-369-41-amdt-10-main-rotor-blade-root-fitting-assembly-and-hub-lead-lag-link-assemblies/documents"}}