{"id":"F2006B08854","name":"AD/DH 104/10 Amdt 1 - Mainplane Upper and Lower Spar Booms - Inspection","slug":"ad-dh-104-10-amdt-1-mainplane-upper-and-lower-spar-booms-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":52053,"registerId":"commonwealth-F2006B08854-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/DH 104/10 Amdt 1 - Mainplane Upper and Lower Spar Booms - 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)  DH 104 (Dove) Series Aeroplanes\n\n \n\nAD/DH 104/10\n\nAmdt 1\n\nApplicability: All models.\n\n\nMainplane Upper and Lower Spar Booms - Inspection\n\n\n2/73\n\n \n\nRequirement: 1. Inspect the wing upper and lower spar booms for signs of corrosion, and carry out any necessary repairs, in accordance with Hawker Siddeley Aviation Technical News Sheet CT(104) No. 125 Issue 6.\n\n \n\n2. All instances of corrosion are to be reported to the Secretary.\n\n \n\nCompliance: Between ribs 5 and 7 - within 6 months of the previous inspection (DCA/DH 104/10) and thereafter at intervals not exceeding 6 months. Inboard of rib 5 and outboard of rib 7 - within 12 months of the previous inspection (DCA/DH 104/10) and thereafter at intervals not exceeding 12 months.\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 targeted safety directive for a specific aircraft type's wing structure. It remains focused on its original purpose: ensuring structural integrity of DH 104 Dove aircraft through periodic inspection. The amendment appears to update inspection intervals or procedures without expanding beyond the original safety scope."},"complexity_factors":["Very short document (approximately 200 words)","Only 2 substantive requirements plus compliance timing","Single defined technical reference (Hawker Siddeley Technical News Sheet)","Simple conditional structure based on wing rib locations (ribs 5-7 vs other areas)","No nested exceptions or complex cross-referencing to other legislation","Straightforward compliance timeline (6-month and 12-month intervals)"],"plain_english_summary":"**What this is:** This is an Airworthiness Directive (AD) — essentially a mandatory safety notice issued by Australia's Civil Aviation Safety Authority (CASA) for a specific aircraft type.\n\n**Who it affects:** Owners and operators of **DH 104 (Dove) series aeroplanes** — a British twin-engine aircraft from the 1940s-60s still flying in Australia.\n\n**What it requires:**\n- **Inspection of wing spar booms** — the main structural beams running through the wings that carry flight loads. These must be checked for **corrosion** (rust or deterioration of the metal).\n- **Repairs** must be done if corrosion is found, following a specific technical guide (Hawker Siddeley Technical News Sheet CT(104) No. 125 Issue 6).\n- **Reporting** — any corrosion found must be reported to the Secretary (of the Department responsible for aviation).\n\n**When it must be done:**\n- **Between ribs 5 and 7** (a specific section of the wing): Every **6 months**\n- **Other wing sections** (inboard of rib 5 and outboard of rib 7): Every **12 months**\n\n**Why it matters:** Wing spar booms are critical structural components. If they corrode and fail, the wing could break off in flight. This AD ensures ongoing monitoring of aging aircraft structures to prevent catastrophic accidents.\n\n**Note:** This is **Amendment 1** (Amdt 1) of an existing directive, meaning it updates or revises earlier requirements (originally issued as DCA/DH 104/10)."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"This instrument is labelled Amendment 1 to AD/DH 104/10 and prescribes model‑wide inspection intervals and mandatory reporting (Amdt 1; Applicability; Requirement; Compliance). The source text here is the amendment itself; the original AD text is not included, so a line‑by‑line comparison cannot be made from this document alone, but the amendment status indicates the AD modifies the prior instrument."},"complexity_factors":["Cross-reference to external technical document (Hawker Siddeley CT(104) No.125 Issue 6) creates dependency on an external specification (Requirement 1).","Two-tiered calendar inspection intervals create recurring compliance scheduling (Compliance: 6‑month and 12‑month intervals).","Mandatory reporting requirement centralises information flow to the Secretary (Requirement 2), adding administrative burden.","Applicability to all DH 104 models broadens operational scope (Applicability: All models).","Amendment status (Amdt 1) and references to the prior AD (DCA/DH 104/10) require cross-checking earlier material to determine exact changes."],"plain_english_summary":"This airworthiness directive (AD/DH 104/10 Amdt 1) requires operators of DH 104 (Dove) series aeroplanes to inspect the wing upper and lower spar booms for corrosion and carry out any necessary repairs, following Hawker Siddeley Aviation Technical News Sheet CT(104) No.125 Issue 6 (Requirement 1). All corrosion must be reported to the Secretary (Requirement 2). Inspections are recurring: between ribs 5–7 every 6 months; inboard of rib 5 and outboard of rib 7 every 12 months (Compliance). Operators pay for inspections/repairs and must file reports; the AD creates a recurring compliance cost and administrative reporting obligation."}},"importantCases":[],"_links":{"self":"/api/acts/ad-dh-104-10-amdt-1-mainplane-upper-and-lower-spar-booms-inspection","history":"/api/acts/ad-dh-104-10-amdt-1-mainplane-upper-and-lower-spar-booms-inspection/history","analysis":"/api/acts/ad-dh-104-10-amdt-1-mainplane-upper-and-lower-spar-booms-inspection/analysis","conflicts":"/api/acts/ad-dh-104-10-amdt-1-mainplane-upper-and-lower-spar-booms-inspection/conflicts","importantCases":"/api/acts/ad-dh-104-10-amdt-1-mainplane-upper-and-lower-spar-booms-inspection/important-cases","documents":"/api/acts/ad-dh-104-10-amdt-1-mainplane-upper-and-lower-spar-booms-inspection/documents"}}