{"id":"F2006B08862","name":"AD/DH 104/18 Amdt 1 - Trim Tab Connecting Rod Eye End","slug":"ad-dh-104-18-amdt-1-trim-tab-connecting-rod-eye-end","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":52061,"registerId":"commonwealth-F2006B08862-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/DH 104/18 Amdt 1 - Trim Tab Connecting Rod Eye End","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 104/18\n\nAmdt 1\n\n\nTrim Tab Connecting Rod Eye End 11/91\n\n \n\nApplicability: Model DH 104 series.\n\n \n\nRequirement: Remove the rudder and elevators, and the rudder and elevator trim tab connecting rod assemblies; carry out an inspection for cracking of the eye ends P/N CM-2A and\n\nCM-2B.\n\n \n\nNote: Hawker Siddeley Technical News sheet CT (104) No. 187 issue 1 refers.\n\n \n\nCompliance: At each check 4 inspection. The compliance time of the previous issue of this Directive was at intervals not exceeding 500 hours time in service.\n\n \n\nBackground: A cracked eye end was found on a Heron aircraft elevator trim tab connecting rod.\n\nThe same part is fitted to Dove aircraft. This amendment extends compliance to align with Country of Origin AD.\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 amendment maintains the original safety purpose (preventing trim tab failures due to cracked eye ends). The only change is aligning the inspection interval with existing maintenance schedules rather than a standalone hourly limit — this is an administrative simplification, not scope creep."},"complexity_factors":["Very short document (under 200 words)","Only 2 defined part numbers (CM-2A, CM-2B)","Single mechanical inspection requirement with clear physical actions","No cross-references to other legislation beyond a technical news sheet citation","Simple compliance trigger (scheduled maintenance interval)","Narrow applicability (single aircraft model series)"],"plain_english_summary":"This CASA Airworthiness Directive requires owners, operators and maintainers of de Havilland DH 104 Dove aircraft to inspect the eye end of rudder and elevator trim-tab connecting rods (parts CM-2A/CM-2B) for cracks. \n\nAmendment 1 shifts the inspection timing from every 500 flight hours to the existing \"check 4\" maintenance interval to match UK practice, reducing the risk of trim-system failure after a similar crack was found on a Heron."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"Amendment alters the compliance timing. The prior directive required inspections at intervals not exceeding 500 hours time in service; the amendment requires inspection at each \"check 4\" maintenance inspection to align with the Country of Origin AD, changing when operators must perform the inspection and thus the maintenance scheduling burden."},"complexity_factors":["Technical specificity: inspection targets identified by part numbers (P/N CM-2A, CM-2B).","Physical work scope: requires removal of rudder, elevators and connecting rod assemblies for inspection.","Compliance-timing ambiguity: uses the maintenance term \"check 4\" which requires reference to approved maintenance schedules to determine exact interval.","Cross-jurisdiction alignment: amendment synchronises timing with Country of Origin AD, creating reliance on foreign AD cadence.","Procedural dependency: refers to Hawker Siddeley Technical News CT (104) No.187 for additional guidance.","Fleet effect: applies to entire DH 104 series, concentrating costs on operators of that type."],"plain_english_summary":"Requires operators of DH 104 (Dove) aircraft to remove the rudder and elevators and the rudder/elevator trim‑tab connecting rod assemblies to inspect the rod eye ends (P/N CM‑2A and CM‑2B) for cracking. Operators must carry out this inspection at each \"check 4\" maintenance inspection.\n\nThe change responds to a cracked eye end found on a Heron and aligns the inspection timing with the Country of Origin AD. Aircraft operators bear the inspection, removal and reinstallation costs; the regulator enforces compliance."}},"importantCases":[],"_links":{"self":"/api/acts/ad-dh-104-18-amdt-1-trim-tab-connecting-rod-eye-end","history":"/api/acts/ad-dh-104-18-amdt-1-trim-tab-connecting-rod-eye-end/history","analysis":"/api/acts/ad-dh-104-18-amdt-1-trim-tab-connecting-rod-eye-end/analysis","conflicts":"/api/acts/ad-dh-104-18-amdt-1-trim-tab-connecting-rod-eye-end/conflicts","importantCases":"/api/acts/ad-dh-104-18-amdt-1-trim-tab-connecting-rod-eye-end/important-cases","documents":"/api/acts/ad-dh-104-18-amdt-1-trim-tab-connecting-rod-eye-end/documents"}}