{"id":"F2006B07548","name":"AD/VAT/16 - Elevator Stops on Torque Shaft - Modification","slug":"ad-vat-16-elevator-stops-on-torque-shaft-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":50142,"registerId":"commonwealth-F2006B07548-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/VAT/16 - Elevator Stops on Torque Shaft - 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)  Victa and A.E.S.L. Airtourer Series Aeroplanes\n\n \n\nAD/VAT/16 Elevator Stops on Torque Shaft - Modification 5/64\n\nApplicability: Victa Airtourer 100 and 115. Document:  1. Victa SB No. 30; or\n\n2. Victa Mod. B87. Compliance: Before 1 September 1971.\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\n \n","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The AD as written is narrowly targeted and prescriptive: it applies only to Victa Airtourer 100 and 115 and requires a single physical modification by reference to named technical documents, to be completed by a fixed date. The instrument itself does not indicate any expansion or contraction of scope from an earlier or broader intent within the provided text; it states the applicability, the acceptable documents, and the compliance deadline without amendments or conditional carve-outs."},"complexity_factors":["Narrow applicability: only Victa Airtourer models 100 and 115 are affected (low scope breadth).","Single technical action required (modification of elevator stops on torque shaft) reduces procedural complexity.","Compliance method is constrained to two specified documents, which simplifies decision-making but creates dependency on those documents.","Hard compliance deadline (historical date) but no staged or conditional requirements; timeline simplicity lowers complexity.","Implementation complexity depends on availability and clarity of the referenced technical documents and parts, which are external to the AD text.","No multiple parties, exemptions, or varying thresholds described in the AD itself (reduces regulatory complexity)."],"plain_english_summary":"What this instrument does (mechanics first)\n\n- AD/VAT/16 requires a physical modification to the elevator stop arrangement on the torque shaft of certain small aeroplanes. The modification must be carried out in accordance with one of two specified technical documents: Victa Service Bulletin No. 30 or Victa Modification B87. (AD/VAT/16; Documents: Victa SB No. 30; Victa Mod. B87.)\n\nWho is affected and who decides\n\n- The requirement applies only to Victa Airtourer model 100 and model 115 aircraft. (Applicability: Victa Airtourer 100 and 115.)\n- The Civil Aviation Safety Authority (as publisher of the Schedule of Airworthiness Directives) is the regulatory source issuing the directive; aircraft owners/operators and the mechanics or maintenance organisations that service these aircraft are the parties who must act to comply. (COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 – Schedule of Airworthiness Directives; AD/VAT/16.)\n\nWhat must be done and by when\n\n- Operators must carry out the specified modification before 1 September 1971. (Compliance: Before 1 September 1971.)\n- The directive gives two alternative documents that, if followed, satisfy the requirement: Victa SB No. 30 or Victa Mod. B87. The owner/operator (or their chosen maintenance provider) decides which of those documents to use.\n\nWhy it matters (official claim and practical implications)\n\n- The AD is titled “Elevator Stops on Torque Shaft - Modification,” which identifies the technical target of the intervention; the title implies the action is intended to change the physical stop arrangement on the elevator torque shaft (a control-surface linkage component). The text of the AD itself does not state a narrative safety rationale; it prescribes a mandatory modification by reference to the specified technical documents. (AD/VAT/16.)\n\n- Practical effects: the owner/operator pays for parts, labour and any aircraft downtime required to effect the modification. Compliance shifts maintenance decisions and timing onto owners/operators and their chosen maintenance providers. The AD constrains technical freedom by requiring compliance with one of the two named documents rather than leaving the method open.\n\nCosts, incentives, trade-offs and implementation risks (mechanics, not judgments)\n\n- Who pays: aircraft owners/operators. Costs include parts specified in the bulletin/modification, labour, and opportunity cost from taking the aeroplane out of service to perform the work. (Documents: Victa SB No. 30; Victa Mod. B87; Compliance: Before 1 September 1971.)\n\n- Incentives: owners gain the ability to fly legally only if they comply with the AD (the AD sets the mandatory action). Operators have the discrete choice between two prescribed technical documents; that choice determines which parts and procedures are used and which maintenance organisation can perform the work effectively.\n\n- Trade-offs and risks: following a specified service bulletin or modification reduces ambiguity about what must be done, but it creates dependency on the availability and clarity of those documents and any parts they require. If the documents are scarce or unclear, implementation may be delayed, increasing downtime and cost. The AD does not itself allocate funding or technical support; responsibility rests with owners/operators and maintenance providers.\n\n- Effects on private enterprise and markets: the AD imposes a compliance cost on owners and creates possible demand for parts and maintenance labour for those specific Victa Airtourer models. Independent maintenance organisations can perform the work provided they follow the specified documents; the AD does not on its face limit who may perform the work.\n\nSummary sentence\n\n- In short, AD/VAT/16 requires owners/operators of Victa Airtourer 100 and 115 aeroplanes to modify the elevator stops on the torque shaft according to Victa SB No. 30 or Victa Mod. B87, and to complete that work before 1 September 1971. (AD/VAT/16; Applicability; Documents; Compliance.)"},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, single-purpose airworthiness directive targeting a specific mechanical modification on specific aircraft models. It has not expanded beyond its original safety purpose."},"complexity_factors":["Extremely short document (approximately 150 words)","Only 2 defined applicability criteria (specific aircraft models)","Single compliance requirement with clear deadline","No cross-references to other legislation or regulations beyond the parent Civil Aviation Regulations 1998","No conditional logic or nested exceptions","Simple binary compliance path (follow either Document 1 OR Document 2)"],"plain_english_summary":"**What this is:** This is an **Airworthiness Directive (AD)** — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA) that requires specific repairs or modifications to aircraft.\n\n**What it does:** This directive (AD/VAT/16) orders owners and operators of **Victa Airtourer 100 and 115** aircraft to modify the **elevator stops on the torque shaft**. The elevator is the control surface that makes the plane pitch up and down; the \"stops\" are physical limits that prevent the elevator from moving too far. The torque shaft is part of the control mechanism. This modification prevents potential control system failures.\n\n**Who it affects:** Anyone who owns or operates these specific Victa Airtourer aircraft models.\n\n**What they must do:** \n- Follow either **Victa Service Bulletin No. 30** or **Victa Modification B87** (these are manufacturer instructions for the fix)\n- Complete the work **before 1 September 1971**\n\n**Why it matters:** Airworthiness Directives are legally binding. Flying an aircraft without complying with an AD is illegal and dangerous. This particular directive addresses a safety-critical flight control issue that could affect the aircraft's ability to maneuver safely."}},"importantCases":[],"_links":{"self":"/api/acts/ad-vat-16-elevator-stops-on-torque-shaft-modification","history":"/api/acts/ad-vat-16-elevator-stops-on-torque-shaft-modification/history","analysis":"/api/acts/ad-vat-16-elevator-stops-on-torque-shaft-modification/analysis","conflicts":"/api/acts/ad-vat-16-elevator-stops-on-torque-shaft-modification/conflicts","importantCases":"/api/acts/ad-vat-16-elevator-stops-on-torque-shaft-modification/important-cases","documents":"/api/acts/ad-vat-16-elevator-stops-on-torque-shaft-modification/documents"}}