{"id":"F2006B10697","name":"AD/HU 369/35 Amdt 1 - Tail Rotor Hub - Inspection and Modification","slug":"ad-hu-369-35-amdt-1-tail-rotor-hub-inspection-and-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":116658,"registerId":"commonwealth-F2006B10697-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/HU 369/35 Amdt 1 - Tail Rotor Hub - 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)  McDonnell Douglas (Hughes) and Kawasaki 369 Series Helicopters\n\n \n\nAD/HU 369/35\n\nAmdt 1\n\n\nTail Rotor Hub - Inspection and Modification 4/79\n\n \n\nApplicability: All 500 model 369D series with tail rotor hub assemblies and tail rotor blade attachment bolts as listed in Hughes SIN No. DN-27.1.\n\n \n\nDocument: Hughes SIN No. DN-27.1. Compliance:  As per requirement document.\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":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a standard, narrow Airworthiness Directive focused on a specific mechanical component (tail rotor hub) on a specific aircraft model. It has not expanded beyond its original safety purpose. The 'Amdt 1' indicates this is an amendment to a previous directive, likely updating applicability or reference documents, but the core scope remains targeted at the same safety issue."},"complexity_factors":["Very short document (approximately 150 words of substantive content)","Only 1 defined reference (Hughes SIN No. DN-27.1) — the actual technical requirements are outsourced to this external document","No conditional logic or nested exceptions within the directive itself","Simple applicability test: specific model series with specific components","Single compliance pathway: 'As per requirement document'","No cross-references to other legislation or regulations beyond the enabling authority (Civil Aviation Regulations 1998, Part 39)"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** — essentially a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA) for specific helicopters.\n\n**What it does:**\n- Requires owners and operators of certain McDonnell Douglas (formerly Hughes) and Kawasaki 369 series helicopters to inspect and modify the **tail rotor hub** — the part that holds the tail rotor blades.\n- The work must follow the instructions in a specific Hughes Service Information Notice (SIN No. DN-27.1).\n\n**Who it affects:**\n- Owners and operators of **500 model 369D series helicopters** that have specific tail rotor hub assemblies and blade attachment bolts listed in that service document.\n\n**Why it matters:**\n- Tail rotor failures can cause catastrophic accidents. This directive ensures potentially dangerous components are identified and fixed before they fail in flight. Compliance is **mandatory** — you cannot legally fly the aircraft until the work is done as specified."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The amendment text provided restates applicability and mandates compliance with Hughes SIN No. DN-27.1 for inspection and modification of the tail rotor hub and blade attachment bolts (Applicability; Document; Compliance). The excerpt does not indicate an expansion or narrowing of the class of affected aircraft or a change in the substantive requirement compared to the base AD text; no explicit scope change is stated in this amendment excerpt."},"complexity_factors":["Short, single-purpose directive — the AD imposes one requirement (inspection/modification) rather than multiple interlocking obligations.","Relies on an external technical document (Hughes SIN No. DN-27.1) for all substantive procedures and acceptance criteria, shifting complexity to that document (Document: Hughes SIN No. DN-27.1; Compliance: As per requirement document).","Applicability is narrowly defined to a specific model and listed parts, which simplifies identification but requires cross-checking serials/parts lists in the referenced SIN (Applicability).","The AD excerpt does not include timing, enforcement, or alternative compliance pathways, which reduces textual complexity but increases practical uncertainty for implementers.","Administrative clarity in who is covered (all specified 369D 500 models) lowers legal ambiguity but leaves operational details to maintenance organisations and the SIN."],"plain_english_summary":"This directive requires owners/operators of 500‑model 369D helicopters with the specified tail rotor hub assemblies and blade attachment bolts to perform inspections and any modifications per Hughes Service Information Notice No. DN‑27.1. It creates a legal obligation on operators (and their maintenance providers) to obtain and follow that document and bear the cost; the AD delegates technical detail, timeframes, and compliance specifics to the referenced SIN."}},"importantCases":[],"_links":{"self":"/api/acts/ad-hu-369-35-amdt-1-tail-rotor-hub-inspection-and-modification","history":"/api/acts/ad-hu-369-35-amdt-1-tail-rotor-hub-inspection-and-modification/history","analysis":"/api/acts/ad-hu-369-35-amdt-1-tail-rotor-hub-inspection-and-modification/analysis","conflicts":"/api/acts/ad-hu-369-35-amdt-1-tail-rotor-hub-inspection-and-modification/conflicts","importantCases":"/api/acts/ad-hu-369-35-amdt-1-tail-rotor-hub-inspection-and-modification/important-cases","documents":"/api/acts/ad-hu-369-35-amdt-1-tail-rotor-hub-inspection-and-modification/documents"}}