{"id":"F2006B07565","name":"AD/VAT/31 Amdt 1 - Control Torque Tube Assembly - Inspection","slug":"ad-vat-31-amdt-1-control-torque-tube-assembly-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":50160,"registerId":"commonwealth-F2006B07565-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/VAT/31 Amdt 1 - Control Torque Tube Assembly - 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)  Victa and A.E.S.L. Airtourer Series Aeroplanes\n\n \n\nAD/VAT/31\n\nAmdt 1\n\n\nControl Torque Tube Assembly - Inspection 9/79\n\n \n\nApplicability: Airtourer 100 and 115.\n\n \n\nRequirement: Inspect both upper and lower cut outs in the Control Column Torque Tube P/N 52131/30 for cracking. The area can be inspected by removing the arm rest front panel P/N 53018/1.\n\n \n\nCompliance: At intervals not exceeding 100 hours time in service after 30 September 1979.\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":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a standard, narrow Airworthiness Directive focused on a specific safety-critical inspection for a particular aircraft type. It has not expanded beyond its original purpose of ensuring structural integrity of the control system."},"complexity_factors":["Very short document (approximately 150 words)","Only 2 defined terms implicitly referenced (part numbers)","No cross-references to other legislation or regulations","Simple conditional logic: single compliance deadline with recurring interval","No exceptions, exemptions, or nested conditions","Single applicability criterion (aircraft model)","Straightforward mechanical inspection requirement"],"plain_english_summary":"This is an **Airworthiness Directive** — a mandatory safety instruction issued by Australia's Civil Aviation Safety Authority (CASA) for specific aircraft.\n\n**What it does:**\nOrders owners and operators of **Victa and A.E.S.L. Airtourer 100 and 115 aeroplanes** to inspect a specific part called the **Control Column Torque Tube** (part number 52131/30) for cracks. The inspection focuses on the upper and lower cut-outs in this tube.\n\n**How to do it:**\nRemove the arm rest front panel (part number 53018/1) to access the area.\n\n**When to do it:**\nEvery **100 hours of flight time** (\"time in service\") after 30 September 1979.\n\n**Why it matters:**\nCracks in the control torque tube could lead to control system failure — potentially causing loss of aircraft control. This directive prevents accidents by catching fatigue damage before it becomes critical.\n\n**Who it affects:**\nAnyone operating or maintaining the specified Airtourer aircraft models in Australia."},"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The supplied text contains a single, focused directive: periodic inspection of the Control Column Torque Tube P/N 52131/30 for cracking on Airtourer 100 and 115, with access via arm rest front panel P/N 53018/1 and a 100-hour interval after 30 September 1979 (Applicability, Requirement, Compliance). The instrument as provided does not indicate any change in scope from an earlier or original intent; it sets out the applicable aircraft, the part to be inspected, the access method, and the inspection interval."},"complexity_factors":["Narrow technical scope: applies only to Airtourer 100 and 115 (Applicability).","Prescriptive, single-step requirement: inspect specified cut-outs on P/N 52131/30 (Requirement).","Fixed, simple compliance interval: every 100 hours after a specified date (Compliance).","Technical detail requires parts identification (P/N 52131/30 and P/N 53018/1), which may require maintenance documentation to implement (Requirement).","Lack of specified acceptance criteria or mandated corrective actions increases implementation judgment for maintenance providers (Requirement)."],"plain_english_summary":"What this instrument does\n\n- This Airworthiness Directive (AD) requires a recurring inspection of a specific part on certain small aircraft. It applies to Victa/A.E.S.L. Airtourer models 100 and 115. (Applicability)\n\n- The required action is a visual inspection of both the upper and lower cut-outs in the Control Column Torque Tube, part number (P/N) 52131/30, looking for cracking. The inspection can be carried out by removing the arm rest front panel, P/N 53018/1, to access the area. (Requirement)\n\n- The inspection must be carried out at intervals not exceeding 100 hours time in service, starting after 30 September 1979. (Compliance)\n\nWho is affected and who decides\n\n- Aircraft owners/operators of Airtourer 100 and 115 must ensure the inspections are done on the listed torque tube part. (Applicability, Requirement, Compliance)\n\n- The Civil Aviation Safety Authority (CASA), acting under the Civil Aviation Regulations and the Schedule of Airworthiness Directives, has issued this directive; operators and maintenance providers implement it. (header: Schedule of Airworthiness Directives)\n\nWhy it matters and how it changes behaviour\n\n- The directive changes maintenance practice for the affected aircraft by introducing a mandatory, periodic inspection for cracking in a named torque-tube component. Operators must schedule and pay for inspections at the prescribed 100-hour intervals and, if cracks are found, will likely need additional maintenance or part replacement (the AD does not specify follow-up repairs in this text). (Requirement, Compliance)\n\nCosts, incentives and trade-offs (mechanical, not normative)\n\n- Who pays: Owners/operators bear the direct costs of inspection labour, possible downtime, and any repairs or part replacements discovered by inspections. (Applicability, Requirement, Compliance)\n\n- Incentives: The AD creates an incentive for operators to monitor and maintain the specified torque tube to avoid airworthiness non-compliance. Maintenance providers receive work from inspections and any required repairs.\n\n- Compliance burden and implementation risk: The inspection requires removal of a specific panel (P/N 53018/1) to access the cut-outs, which imposes a repeated maintenance task every 100 hours. The AD specifies what to inspect but does not set out tolerances, detailed inspection technique, or mandatory corrective actions in the supplied text, leaving judgment about defect severity and remedial steps to the operator or maintenance organisation. (Requirement)\n\n- Trade-offs and opportunity costs: Regular inspections consume maintenance shop time and resources that could be used for other maintenance tasks. If cracking is found, replacing or repairing the torque tube will add parts and labour costs and aircraft downtime.\n\nEffects on private choice and market participants\n\n- The directive constrains operator choices by mandating inspection intervals and a defined inspection area for a particular part; operators can choose how to perform the inspection (in-house or contract a maintenance provider) but must meet the interval. The AD concentrates obligations on owners/operators of the two listed aircraft models and generates recurring business for maintenance providers familiar with the specified part numbers. (Applicability, Requirement, Compliance)\n\nImplementation note\n\n- The AD is prescriptive about what to inspect, where (P/N 52131/30 cut-outs), and how often (every 100 hours after 30/9/1979), but the supplied text does not describe inspection acceptance criteria, non-compliance consequences, or corrective procedures if cracking is found. That omission creates scope for maintenance judgment when deciding next steps after a crack is detected. (Requirement, Compliance)"}},"importantCases":[],"_links":{"self":"/api/acts/ad-vat-31-amdt-1-control-torque-tube-assembly-inspection","history":"/api/acts/ad-vat-31-amdt-1-control-torque-tube-assembly-inspection/history","analysis":"/api/acts/ad-vat-31-amdt-1-control-torque-tube-assembly-inspection/analysis","conflicts":"/api/acts/ad-vat-31-amdt-1-control-torque-tube-assembly-inspection/conflicts","importantCases":"/api/acts/ad-vat-31-amdt-1-control-torque-tube-assembly-inspection/important-cases","documents":"/api/acts/ad-vat-31-amdt-1-control-torque-tube-assembly-inspection/documents"}}