{"id":"F2006B01813","name":"AD/A109/28 - Tail Rotor Blade Grip Assemblies","slug":"ad-a109-28-tail-rotor-blade-grip-assemblies","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":41011,"registerId":"commonwealth-F2006B01813-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/A109/28 - Tail Rotor Blade Grip Assemblies","content":"---\nmeta-content-style-type: text/css\nmeta-content-type: application/xhtml+xml; charset=utf-8\nmeta-description: CASA Airworthiness Directive\nmeta-generator: Aspose.Words for .NET 22.10.0\nmeta-keywords: Issue 7/1997,Rotorcraft,Agusta A109 Series Helicopters,Tail Rotor Blade Grip Assemblies,28\ntitle: Airworthiness Directive - AD/A109/28 - Tail Rotor Blade Grip Assemblies\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)  Agusta A109 Series Helicopters\n\n \n\nAD/A109/28 Tail Rotor Blade Grip Assemblies 7/97\n\nDM\n\nApplicability: All A109C up to Serial Number 7670, excluding 7630, 7633, 7645, 7651, 7653, 7657,\n\n7661, 7663, 7665, 7667, and 7669.\n\n \n\nRequirement: Action in accordance with Agusta Bollettino Tecnico No. 109-100, Rev A.\n\n \n\nNote: RAI AD 97-084 refers.\n\n \n\nCompliance: Before 30 June 1997.\n\n \n\nThis Airworthiness Directive becomes effective on 14 May 1997.\n\n \n\nBackground: Cracking has been discovered in the grip assemblies P/N 109-8131-05-109 and -113.\n\nThis Directive is issued to replace the grip assemblies with an improved item and rework of the blades to accept larger diameter bolts.\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 mechanical defect in a specific helicopter model. It has not expanded beyond its original safety purpose."},"complexity_factors":["Very short document (approximately 150 words of substantive content)","Only 3 defined elements: applicability range, specific part numbers, and referenced technical document","Single straightforward requirement with no conditional logic or exceptions beyond the serial number exclusions","No cross-references to other legislation beyond a single note referencing a related airworthiness directive (RAI AD 97-084)","Clear, unambiguous compliance deadline with no alternative compliance methods or phased implementation"],"plain_english_summary":"This CASA Airworthiness Directive mandates replacement of cracked tail rotor blade grip assemblies (and rework of blades for larger bolts) on Agusta A109C helicopters with serials up to 7670, excluding 7630, 7633, 7645, 7651, 7653, 7657, 7661, 7663, 7665, 7667 and 7669. \n\nEffective 14 May 1997, compliance is required before 30 June 1997 by following Agusta Bollettino Tecnico No. 109-100, Rev A to prevent catastrophic rotor failure."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The AD implements the stated original intent: address discovered cracking by replacing specified grip assemblies and reworking blades on listed A109C helicopters. The scope is limited to the serial-number range with listed exclusions and directs compliance with the Agusta technical bulletin; it does not expand beyond those measures."},"complexity_factors":["Narrow applicability by serial number with explicit exclusions (Applicability).","Identification of specific affected parts by part number (Background: P/N 109-8131-05-109 and -113).","Mandated compliance with a manufacturer technical bulletin (Requirement: Agusta Bollettino Tecnico No. 109-100, Rev A).","Fixed compliance deadline and effective date (Compliance; effective date 14 May 1997; compliance before 30 June 1997).","Technical nature of work: part replacement and blade rework to accept larger bolts (Background/Requirement) — requires parts, tooling and maintenance time.","Operational and logistical implications for operators: scheduling, parts procurement and aircraft downtime (implicit in Compliance/Requirement)."],"plain_english_summary":"This Airworthiness Directive requires owners/operators of specified Agusta A109C helicopters (all up to serial number 7670, with several serials excluded) to replace tail-rotor blade grip assemblies (P/N 109-8131-05-109 and -113) with an improved item and to rework blades to accept larger-diameter bolts, following Agusta Bollettino Tecnico No. 109-100 Rev A. CASA issued the AD; compliance was required before 30 June 1997 (effective 14 May 1997). Owners/operators must arrange and fund the work and schedule affected helicopters for the mandated maintenance."}},"importantCases":[],"_links":{"self":"/api/acts/ad-a109-28-tail-rotor-blade-grip-assemblies","history":"/api/acts/ad-a109-28-tail-rotor-blade-grip-assemblies/history","analysis":"/api/acts/ad-a109-28-tail-rotor-blade-grip-assemblies/analysis","conflicts":"/api/acts/ad-a109-28-tail-rotor-blade-grip-assemblies/conflicts","importantCases":"/api/acts/ad-a109-28-tail-rotor-blade-grip-assemblies/important-cases","documents":"/api/acts/ad-a109-28-tail-rotor-blade-grip-assemblies/documents"}}