{"id":"F2006B04382","name":"AD/BELL 205/46 - Anti-Torque Control System - Modification to Pushrod Status","slug":"ad-bell-205-46-anti-torque-control-system-modification-to-pushrod-status","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":44207,"registerId":"commonwealth-F2006B04382-current","compilationNumber":null,"startDate":"2026-04-02","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/BELL 205/46 - Anti-Torque Control System - Modification to Pushrod Status","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\nBell Helicopter Textron 205 Series Helicopters\n\n \n\nAD/BELL 205/46 Anti-Torque Control System - Modification\n\nto Pushrod Status\n\n\n12/79\n\n \n\nApplicability: All model 205A-1. Document: 1 Bell SB No. 205-78-5; or\n\n2. FAA AD 76-12-07, revised September 21, 1979. Compliance: Before 31 December 1979.\n\nBackground: Numerous cases have occurred of cracking to tail rotor control chain links. the manufacturer has introduced an alternative control system which utilises pushrods.\n","sortOrder":0}],"analysis":{"kimi_summary":{"_metrics":{"model":"kimi-k2.5","source":"moonshot-batch","completionTokens":1447},"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"The directive maintains its original narrow scope: mandating a specific safety modification to replace a defective tail rotor control chain with a pushrod system on a specific helicopter model. No expansion beyond the original airworthiness safety purpose is evident."},"complexity_factors":["Extremely short instrument (under 150 words)","Single applicability criterion limited to Bell model 205A-1 helicopters","Single unconditional compliance requirement with a hard deadline","No defined terms, exceptions, or conditional provisions","Defers all technical details to external reference documents rather than including them in the legislative text"],"plain_english_summary":"This Airworthiness Directive (AD) is a **mandatory safety order** issued by the Civil Aviation Safety Authority for Bell 205A-1 helicopters.\n\n**What it requires**\nHelicopter owners must modify the **anti-torque control system** (the mechanism that controls the tail rotor, which prevents the helicopter from spinning uncontrollably) before 31 December 1979.\n\n**Why it matters**\nThe original design uses a chain to control the tail rotor. Multiple cases have been found where these **chain links crack and fail**, which could cause the pilot to lose control of the tail rotor and crash. Bell Helicopter has developed a safer replacement using **pushrods** (solid metal rods) instead of chains.\n\n**How to comply**\nFollow the technical instructions in either:\n* Bell Service Bulletin No. 205-78-5, or\n* FAA Airworthiness Directive 76-12-07 (revised September 1979)\n\n**Who is affected**\nAnyone who owns or operates a Bell 205A-1 helicopter."}},"importantCases":[],"_links":{"self":"/api/acts/ad-bell-205-46-anti-torque-control-system-modification-to-pushrod-status","history":"/api/acts/ad-bell-205-46-anti-torque-control-system-modification-to-pushrod-status/history","analysis":"/api/acts/ad-bell-205-46-anti-torque-control-system-modification-to-pushrod-status/analysis","conflicts":"/api/acts/ad-bell-205-46-anti-torque-control-system-modification-to-pushrod-status/conflicts","importantCases":"/api/acts/ad-bell-205-46-anti-torque-control-system-modification-to-pushrod-status/important-cases","documents":"/api/acts/ad-bell-205-46-anti-torque-control-system-modification-to-pushrod-status/documents"}}