{"id":"F2006B04681","name":"AD/BELL 412/8 - Installation of Main Rotor Droop Restraint Kit and Cyclic Stick Centring Indicator","slug":"ad-bell-412-8-installation-of-main-rotor-droop-restraint-kit-and-cyclic-stick-centring-indicator","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":44433,"registerId":"commonwealth-F2006B04681-current","compilationNumber":null,"startDate":"2026-04-02","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/BELL 412/8 - Installation of Main Rotor Droop Restraint Kit and Cyclic Stick Centring Indicator","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)  Bell Helicopter Textron 412 Series Helicopters\n\n \n\n# AD/BELL 412/8 Installation of Main Rotor Droop Restraint\n\nKit and Cyclic Stick Centring Indicator\n\nApplicability: All models with S/Nos. prior to 33101. Document:  Bell Alert Service Bulletin No. 412-83-11. Compliance:               1 September 1983.\n\n# 6/83\n\nBackground:  These modifications result from BHT investigations of main rotor yoke cracking. They are designed to prevent excessive main rotor yoke loads while the aircraft is parked, and during ground operation.\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":{"_metrics":{"model":"kimi-k2.5","source":"moonshot-batch","completionTokens":1470},"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This directive maintains a tightly focused scope limited to a specific airworthiness defect (main rotor yoke cracking) in a defined subset of Bell 412 helicopters. It does not expand beyond the original safety purpose into broader operational, maintenance, or certification requirements."},"complexity_factors":["Single discrete technical mandate with no subordinate conditions","Clear applicability criteria based solely on aircraft serial number","No defined terms section or interpretive provisions","Self-contained requirement without nested exceptions or cross-references to other legislative instruments beyond the parent Civil Aviation Regulations"],"plain_english_summary":"This Airworthiness Directive orders owners of Bell 412 helicopters with serial numbers below 33101 to install two mechanical safety devices — a Main Rotor Droop Restraint Kit and a Cyclic Stick Centering Indicator — by 1 September 1983. The modifications prevent main rotor yoke cracking during parked or ground handling by restraining rotor movement and keeping controls centred, averting possible catastrophic failure."}},"importantCases":[],"_links":{"self":"/api/acts/ad-bell-412-8-installation-of-main-rotor-droop-restraint-kit-and-cyclic-stick-centring-indicator","history":"/api/acts/ad-bell-412-8-installation-of-main-rotor-droop-restraint-kit-and-cyclic-stick-centring-indicator/history","analysis":"/api/acts/ad-bell-412-8-installation-of-main-rotor-droop-restraint-kit-and-cyclic-stick-centring-indicator/analysis","conflicts":"/api/acts/ad-bell-412-8-installation-of-main-rotor-droop-restraint-kit-and-cyclic-stick-centring-indicator/conflicts","importantCases":"/api/acts/ad-bell-412-8-installation-of-main-rotor-droop-restraint-kit-and-cyclic-stick-centring-indicator/important-cases","documents":"/api/acts/ad-bell-412-8-installation-of-main-rotor-droop-restraint-kit-and-cyclic-stick-centring-indicator/documents"}}