{"id":"F2006B08946","name":"AD/DH114/35 Amdt 2 - Aircraft Life Extension","slug":"ad-dh114-35-amdt-2-aircraft-life-extension","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":52573,"registerId":"commonwealth-F2006B08946-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/DH114/35 Amdt 2 - Aircraft Life Extension","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)  DH114 (Heron) Series Aeroplanes\n\n \n\nAD/DH114/35\n\nAmdt 2\n\n\nAircraft Life Extension NK\n\n \n\nApplicability: All models incorporating life extension by wing modification or replacement. Document:               For Series 1B aeroplanes: British Aerospace TNS Heron (114) No. M.11, Issue 2.\n\nFor Series 2 aeroplanes: British Aerospace TNS Heron (114) No. M.9, Issue 4.\n\n \n\nCompliance: As detailed in the requirement documents.\n\n \n\nNote: The safe lives referred to in para. 1.1 of each requirement document are superseded by those promulgated in the current issue of AD/DH114/13. The manufacturer has advised that the aircraft life cannot be extended beyond two wing spar boom lifetimes.\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":true,"description":"This amendment updates which safe-life figures apply by stating that the safe lives in paragraph 1.1 of each requirement document are superseded by the safe lives promulgated in the current issue of AD/DH114/13, and it records the manufacturer’s advice that aircraft life cannot be extended beyond two wing spar boom lifetimes. These points alter the applicable life limits and cap the extent of allowable life extension compared with the earlier text of the requirement documents. (Document; Note)"},"complexity_factors":["Short, narrowly focused directive with few operative paragraphs (low textual complexity).","Dependence on external technical documents (British Aerospace TNS Heron No. M.11 and M.9) for substantive requirements increases practical complexity for implementers.","Cross-reference to another AD (AD/DH114/13) requires readers to consult multiple instruments to determine applicable safe lives.","Technical subject-matter (airframe life limits, wing spar boom lifetimes) requires specialised engineering knowledge to apply; the AD itself is not technical but points to technical sources.","The directive uses broad compliance phrasing (\"As detailed in the requirement documents\"), which creates interpretive work for operators and inspectors."],"plain_english_summary":"This AD applies to DH114 (Heron) aeroplanes whose service life was extended by wing modification or replacement: it makes following the named British Aerospace TNS Heron technical documents mandatory, and replaces the documents’ safe‑life figures with those in AD/DH114/13. The manufacturer also advises no extension beyond two wing spar boom lifetimes.\n\nIt matters to operators and maintenance providers because it fixes the technical standard they must use, limits remaining usable life, and drives inspection, modification, retirement and cost decisions."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This amendment maintains the original narrow scope of regulating life-extended Heron aircraft. It updates document references and clarifies the relationship with the safe life limits in AD/DH114/13, but does not expand beyond the specific aircraft type and modification scenario originally targeted."},"complexity_factors":["Very short document (approximately 150 words of substantive content)","Only 2 defined applicability categories (Series 1B and Series 2)","No nested conditional logic or exceptions","Single cross-reference to another directive (AD/DH114/13)","Straightforward compliance requirement ('as detailed in the requirement documents')","No interpretation section or defined terms"],"plain_english_summary":"This is an **Airworthiness Directive** (a mandatory safety instruction) for a specific type of old British aircraft called the **de Havilland DH114 Heron**.\n\n**What it does:**\n- Sets safety rules for Heron aircraft that have had their **wings modified or replaced** to extend how long they can fly (their \"life extension\").\n- Tells owners which technical documents they must follow depending on their aircraft model (Series 1B or Series 2).\n- **Important limitation:** Even with wing modifications, the manufacturer says these planes **cannot fly longer than two wing spar boom lifetimes** (the spar boom is a critical structural part of the wing).\n\n**Who it affects:**\n- Owners and operators of DH114 Heron aircraft in Australia.\n- Anyone maintaining these vintage aircraft.\n\n**Why it matters:**\nThese are elderly aircraft (first flew in the 1950s). Metal fatigue in wings is a serious safety risk. This directive prevents catastrophic structural failure by capping how long modified wings can be used, even after repairs or replacements. It essentially says: \"You can extend the life, but there's a hard limit — you can't keep patching these planes forever.\""}},"importantCases":[],"_links":{"self":"/api/acts/ad-dh114-35-amdt-2-aircraft-life-extension","history":"/api/acts/ad-dh114-35-amdt-2-aircraft-life-extension/history","analysis":"/api/acts/ad-dh114-35-amdt-2-aircraft-life-extension/analysis","conflicts":"/api/acts/ad-dh114-35-amdt-2-aircraft-life-extension/conflicts","importantCases":"/api/acts/ad-dh114-35-amdt-2-aircraft-life-extension/important-cases","documents":"/api/acts/ad-dh114-35-amdt-2-aircraft-life-extension/documents"}}