{"id":"F2006B03601","name":"AD/BEA 121/7 Amdt 1 - Elevator Torque Tubes","slug":"ad-bea-121-7-amdt-1-elevator-torque-tubes","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":43192,"registerId":"commonwealth-F2006B03601-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/BEA 121/7 Amdt 1 - Elevator Torque Tubes","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)  Beagle B121 (Pup) Series Aeroplanes\n\n \n\n# AD/BEA 121/7\n\nAmdt 1\n\nApplicability: All models.\n\n# Elevator Torque Tubes 2/92\n\n \n\nRequirement: Action in accordance with mandatory British Aerospace SB B121/28 Revision 1. Compliance:              As specified in the Requirement Document.\n\nBackground: A severely corroded torque tube assembly has been found on an aircraft at a major inspection. SB has been revised and made mandatory by UK CAA.\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":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"The directive adopts a revised Service Bulletin and makes compliance with that revised bulletin mandatory. The Background states that the Service Bulletin was revised and made mandatory by the UK CAA, and the Requirement makes action in accordance with that mandatory revised bulletin compulsory (Background; Requirement). The operative scope therefore shifts enforcement from optional/technical guidance to a mandatory regulatory requirement implemented by reference to the external Requirement Document (Requirement; Compliance)."},"complexity_factors":["Directive text is short and references a single external Service Bulletin for technical detail (Requirement: \"Action in accordance with mandatory British Aerospace SB B121/28 Revision 1\").","Compliance specifics (timing, inspection intervals, exact tasks) are delegated to the Requirement Document rather than contained in the directive (Compliance: \"As specified in the Requirement Document\").","Applicability covers all models, which simplifies scope but requires every owner/operator of the model to act (Applicability: \"All models\").","Dependence on an externally revised and mandated document (SB revised and made mandatory by UK CAA) adds administrative linkage and potential version-control issues (Background).","Limited factual detail in the directive itself about costs, recommended remedies or thresholds (Background only notes a single corrosion finding)."],"plain_english_summary":"This directive makes compliance with British Aerospace Service Bulletin B121/28 Revision 1 mandatory for all Beagle B121 (Pup) aircraft, requiring the inspections, repairs or replacements of elevator torque tube assemblies specified in that SB. It affects owners/operators (who bear maintenance costs) and was issued after a severely corroded torque tube was found; the detailed timing and tasks are in the referenced Service Bulletin/Requirement Document."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a standard Airworthiness Directive maintaining its original purpose: mandating a specific safety inspection/repair for a particular aircraft type. No scope creep evident."},"complexity_factors":["Very short document (approximately 150 words of substantive content)","No defined terms section — relies on external technical reference (British Aerospace SB B121/28)","Single, straightforward requirement: comply with external service bulletin","No nested exceptions, conditional logic, or cross-references to other legislation","Minimal regulatory machinery — essentially a pointer to an external technical standard"],"plain_english_summary":"This is an **Airworthiness Directive** — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA). It applies to all models of **Beagle B121 (Pup) aircraft**, a type of light aeroplane.\n\n**What it does:**\n- Requires owners and operators of these aircraft to inspect and potentially repair or replace the **elevator torque tubes** — these are metal tubes that transfer the pilot's control inputs to the elevator (the part of the tail that makes the plane pitch up and down).\n- The work must follow a specific technical bulletin from British Aerospace (SB B121/28 Revision 1).\n\n**Why it matters:**\n- A severely corroded torque tube was discovered during a major inspection. Corrosion weakens the metal, and if the tube fails in flight, the pilot could lose control of the aircraft's pitch — a serious safety risk.\n- The UK aviation regulator (CAA) made this repair mandatory, and Australia is adopting the same requirement to keep these aircraft safe.\n\n**Who must comply:**\n- Anyone who owns, operates, or maintains a Beagle B121 series aircraft in Australia.\n\n**When to comply:**\n- As specified in the British Aerospace service bulletin referenced in the directive."}},"importantCases":[],"_links":{"self":"/api/acts/ad-bea-121-7-amdt-1-elevator-torque-tubes","history":"/api/acts/ad-bea-121-7-amdt-1-elevator-torque-tubes/history","analysis":"/api/acts/ad-bea-121-7-amdt-1-elevator-torque-tubes/analysis","conflicts":"/api/acts/ad-bea-121-7-amdt-1-elevator-torque-tubes/conflicts","importantCases":"/api/acts/ad-bea-121-7-amdt-1-elevator-torque-tubes/important-cases","documents":"/api/acts/ad-bea-121-7-amdt-1-elevator-torque-tubes/documents"}}