{"id":"F2006B08733","name":"AD/DAUPHIN/22 - TRGB Mounting Tripod","slug":"ad-dauphin-22-trgb-mounting-tripod","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":51967,"registerId":"commonwealth-F2006B08733-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/DAUPHIN/22 - TRGB Mounting Tripod","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)  Eurocopter SA 360 and SA 365 (Dauphin) Series Helicopters\n\n \n\nAD/DAUPHIN/22 TRGB Mounting Tripod  3/89 DM\n\n \n\nApplicability: SA 365C, C1, C2, C3 helicopters.\n\n \n\nRequirement: Action in accordance with Aerospatiale SB 01.22A.\n\n \n\nNote: DGAC AD 88-189-030 (B) refers.\n\n \n\nCompliance: Within 50 hours time in service after 25 January 1989 and thereafter every 400 hours time in service.\n\n \n\nBackground: Cracking initiated by corrosion has been detected at the root of one of the three arms of the tail rotor gearbox mounting tripod.\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":3,"scope_assessment":{"changed":false,"description":"The AD's scope, as stated, is narrowly targeted: it applies to SA 365C-family helicopters and to the TRGB mounting tripod because of detected corrosion-initiated cracking (see \"Applicability\" and \"Background\"). The directive requires following Aerospatiale SB 01.22A and prescribes specific compliance intervals; the text does not expand the scope beyond addressing that structural cracking for the listed models."},"complexity_factors":["Limited applicability to four specific helicopter models (SA 365C, C1, C2, C3).","Mandatory compliance schedule with an initial short interval (50 hours TIS) and recurring interval (every 400 hours TIS).","Technical work is specified by reference to an external document (Aerospatiale SB 01.22A) rather than detailed in the AD itself, requiring access to and reliance on that service bulletin.","Simple factual background (corrosion-initiated cracking) but no internal detail on inspection or repair technique in the AD text.","Cross-reference to an overseas authority (DGAC AD 88-189-030 (B)), adding a traceability step for operators who may consult that material."],"plain_english_summary":"### What this directive requires\n\nThis airworthiness directive (AD) requires operators of certain Eurocopter (Dauphin) helicopters to carry out the maintenance actions specified by the manufacturer. Mechanically, it mandates action “in accordance with Aerospatiale SB 01.22A” on the tail rotor gearbox (TRGB) mounting tripod (see \"Requirement: Action in accordance with Aerospatiale SB 01.22A\").\n\n### Which aircraft are affected\n\n- The AD applies to Eurocopter SA 365C, C1, C2 and C3 helicopters (see \"Applicability: SA 365C, C1, C2, C3 helicopters\").\n\n### When the work must be done\n\n- The first required action is within 50 hours time in service after 25 January 1989, and thereafter the specified action must be repeated every 400 hours time in service (see \"Compliance: Within 50 hours time in service after 25 January 1989 and thereafter every 400 hours time in service\").\n\n### Why the directive was issued (stated reason)\n\n- The AD was issued because cracking initiated by corrosion was detected at the root of one of the three arms of the TRGB mounting tripod (see \"Background: Cracking initiated by corrosion has been detected at the root of one of the three arms of the tail rotor gearbox mounting tripod\").\n\n### Who pays and who decides\n\n- Owners/operators of the affected helicopters are the parties required to comply; they are responsible for arranging and paying for the inspections and any corrective work called for by the Aerospatiale service bulletin (mechanism: the AD mandates action per the manufacturer SB; see \"Requirement\").\n- The regulator (Civil Aviation Safety Authority, via this AD) prescribes the requirement and the compliance intervals; the specific technical steps and repairs are determined by reference to Aerospatiale SB 01.22A (see \"Requirement: Action in accordance with Aerospatiale SB 01.22A\").\n\n### Compliance burden and implementation notes\n\n- The AD imposes a recurring inspection/maintenance interval (initial 50 TIS hours after 25 Jan 1989, then every 400 TIS hours) that will affect maintenance scheduling and resources (see \"Compliance\").\n- The AD does not set out the detailed inspection or repair steps itself; it directs operators to the manufacturer service bulletin for the technical procedure. That delegates technical discretion to the manufacturer’s documented method (see \"Requirement\").\n\n### Other references\n\n- The AD notes a related French DGAC airworthiness directive (DGAC AD 88-189-030 (B)) but does not repeat its content (see \"Note: DGAC AD 88-189-030 (B) refers\")."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, targeted safety directive addressing a specific corrosion-induced cracking issue in a particular helicopter component. It has not expanded beyond its original purpose of mandating inspections for this known defect."},"complexity_factors":["Single, specific mechanical component addressed (tail rotor gearbox mounting tripod)","Only 4 helicopter models affected (SA 365C series variants)","Simple compliance structure: one-time initial inspection + recurring interval","No defined terms section or interpretation provisions","No cross-references to other legislation beyond a single referenced service bulletin and foreign AD","Straightforward conditional logic (time-in-service trigger only, no nested conditions)"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** — essentially a mandatory safety notice issued by Australia's Civil Aviation Safety Authority (CASA) for specific helicopters.\n\n**What it does:**\nOrders owners and operators of certain Eurocopter Dauphin helicopters (models SA 365C, C1, C2, and C3) to inspect the **tail rotor gearbox mounting tripod** — a structural component that holds the tail rotor gearbox in place.\n\n**Why it matters:**\nCracks caused by corrosion were found where the tripod arms connect. If left unchecked, this could lead to structural failure of the tail rotor assembly, potentially causing loss of control of the helicopter.\n\n**What must be done:**\n- **First inspection:** Within 50 flight hours after 25 January 1989\n- **Repeat inspections:** Every 400 flight hours thereafter\n- **How:** Follow the procedures in Aerospatiale Service Bulletin 01.22A (the manufacturer's official repair/inspection instructions)\n\n**Who it affects:**\nOperators of the specified Dauphin helicopter models in Australia. The directive references a French aviation authority notice (DGAC AD 88-189-030), showing this was part of an international safety response.\n\nThis is a **prescriptive maintenance requirement** — compliance is legally mandatory, not optional."}},"importantCases":[],"_links":{"self":"/api/acts/ad-dauphin-22-trgb-mounting-tripod","history":"/api/acts/ad-dauphin-22-trgb-mounting-tripod/history","analysis":"/api/acts/ad-dauphin-22-trgb-mounting-tripod/analysis","conflicts":"/api/acts/ad-dauphin-22-trgb-mounting-tripod/conflicts","importantCases":"/api/acts/ad-dauphin-22-trgb-mounting-tripod/important-cases","documents":"/api/acts/ad-dauphin-22-trgb-mounting-tripod/documents"}}