{"id":"F2006B06874","name":"AD/SD3-60/3 - Elevator Tab Linkage - Inspection and Modification","slug":"ad-sd3-60-3-elevator-tab-linkage-inspection-and-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":114754,"registerId":"commonwealth-F2006B06874-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/SD3-60/3 - Elevator Tab Linkage - 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)  Short SD3-60 Series Aeroplanes\n\n \n\nAD/SD3-60/3 Elevator Tab Linkage - Inspection and Modification 1/84\n\nApplicability: All model SD3-60 aircraft with S/Nos SH 3601 to SH 3623. Requirement: 1. Shorts S.B. SD360-55-A02.\n\n2. Shorts S.B. SD360-55-02 modification 7448.\n\n \n\nCompliance: 1. Within 60 hours (\"A\" Check) time in service after 12 December 1983 and thereafter at intervals not exceeding 60 hours (\"A\" check) until modified.\n\n \n\n2. Before 31 March 1984.\n\n \n\nBackground:  Analysis shows that in the event of elevator tab disconnect there could be an unacceptable level of vibration.\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":2,"scope_assessment":{"changed":false,"description":"The directive itself states its applicability (SD3-60 S/Ns SH3601–SH3623) and prescribes the inspection and modification actions by reference to specific Shorts Service Bulletins, with defined compliance intervals and a deadline. The document does not indicate any change to that stated scope."},"complexity_factors":["Narrow and specific applicability: only SD3-60 S/Ns SH3601–SH3623 (Applicability).","Two-step compliance path: a recurring inspection procedure and a one-off modification (Requirement).","Short, fixed timelines: 60‑hour inspection interval until modification; modification required before 31 March 1984 (Compliance).","Technical compliance depends on external documents: named Shorts Service Bulletins set the detailed procedures (Requirement).","Clear stated hazard but no procedural detail in the directive itself (Background vs Requirement) — requires obtaining the SBs for implementation."],"plain_english_summary":"What this directive does (mechanically)\n\n- Applies to all Shorts SD3-60 aircraft with serial numbers SH3601 to SH3623. (Applicability)\n- Requires two actions from the operator/maintenance organisation: 1) carry out the inspection procedure specified in Shorts Service Bulletin SD360-55-A02, and 2) carry out the modification specified in Shorts Service Bulletin SD360-55-02 (modification 7448). (Requirement)\n- Requires the inspection to be done within 60 hours time in service after 12 December 1983 and then at intervals not exceeding 60 hours (that is, during each \"A\" check) until the modification has been completed. The modification itself must be carried out before 31 March 1984. (Compliance)\n\nWhy it was issued (stated purpose)\n\n- The directive states that analysis indicates an elevator tab disconnect could produce an unacceptable level of vibration. The inspection and the modification are required to address that risk. (Background)\n\nWho this affects and who decides\n\n- The directive is addressed to the operators/owners and maintenance organisations responsible for the listed SD3-60 aircraft (Applicability; Requirement). They must decide to schedule and perform the inspections and to carry out the modification by the stated deadlines. The text cites Shorts Service Bulletins as the technical means to comply (Requirement).\n\nWho pays and what behaviour changes\n\n- The operators/owners/maintenance organisations of the affected aircraft will incur the direct costs of performing the required inspections (every 60 hours until modified) and of implementing the modification (Requirement; Compliance). To comply, affected parties must schedule recurrent \"A\" check inspections and arrange for the modification to be completed before the specified date. The directive therefore shifts operator behaviour toward immediate and recurring inspection activity until the modification is installed.\n\nCompliance burden, timing and implementation risk\n\n- The recurring inspection requirement (every 60 hours) generates an ongoing maintenance task and potential additional downtime until the modification is fitted (Compliance).\n- The modification carries a fixed deadline (before 31 March 1984). Failure to complete the modification by that date would leave the operator dependent on the recurring inspections; the directive indicates the inspections are a temporary mitigant pending modification (Compliance; Requirement).\n\nRelation of mechanism to stated purpose, and trade-offs\n\n- The stated safety problem is a potential elevator tab disconnect leading to unacceptable vibration (Background). Mechanically, the directive forces a short-term mitigation (frequent inspections) and a permanent fix (modification). The trade-off is operator time and cost for inspections and for carrying out the modification in a defined timeframe. The directive enforces a manufacturer-prescribed technical solution by reference to the named Service Bulletins (Requirement), which concentrates technical decision-making in the referenced documentation.\n\nNotes on implementation details to check when acting on this directive\n\n- The operator will need access to the two Shorts Service Bulletins named in the Requirement to know the exact inspection and modification procedures (Requirement).\n- The inspection frequency is tied to an \"A\" check cycle of 60 hours time in service in the text; operators must ensure their maintenance scheduling aligns with that interval until modification is completed. (Compliance)\n\nSource citations: Applicability; Requirement; Compliance; Background."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, time-bound safety directive addressing a specific mechanical defect in a limited fleet. It has not expanded beyond its original purpose of mandating inspection and modification of elevator tab linkages."},"complexity_factors":["Single, specific aircraft type and serial number range (narrow applicability)","Only two compliance requirements (inspection and modification)","Clear, fixed deadlines (60-hour intervals and 31 March 1984)","No defined terms section or interpretation provisions","No cross-references to other legislation beyond the parent Civil Aviation Regulations 1998","Straightforward conditional logic (inspect until modified, then stop)"],"plain_english_summary":"This is an **Airworthiness Directive** — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA) for a specific type of aircraft.\n\n**What it does:**\n- Requires owners and operators of **Short SD3-60 Series aeroplanes** (specifically serial numbers SH 3601 to SH 3623) to inspect and modify the **elevator tab linkage** — a mechanical connection that helps control the aircraft's pitch (up and down movement).\n\n**Why it matters:**\n- Engineering analysis found that if the elevator tab disconnects in flight, it could cause **dangerous vibration levels** that might compromise aircraft control. This directive prevents that safety risk.\n\n**What must be done:**\n1. **Repeated inspections:** Check the linkage every 60 flight hours (called an \"A\" Check) starting from 12 December 1983, continuing until the modification is done.\n2. **Permanent fix:** Install modification 7448 (detailed in Shorts Service Bulletin SD360-55-02) before 31 March 1984.\n\n**Who it affects:**\n- Operators of the affected Short SD3-60 aircraft registered in Australia, and any foreign aircraft operating in Australian airspace subject to CASA oversight."}},"importantCases":[],"_links":{"self":"/api/acts/ad-sd3-60-3-elevator-tab-linkage-inspection-and-modification","history":"/api/acts/ad-sd3-60-3-elevator-tab-linkage-inspection-and-modification/history","analysis":"/api/acts/ad-sd3-60-3-elevator-tab-linkage-inspection-and-modification/analysis","conflicts":"/api/acts/ad-sd3-60-3-elevator-tab-linkage-inspection-and-modification/conflicts","importantCases":"/api/acts/ad-sd3-60-3-elevator-tab-linkage-inspection-and-modification/important-cases","documents":"/api/acts/ad-sd3-60-3-elevator-tab-linkage-inspection-and-modification/documents"}}