{"id":"F2006B08745","name":"AD/DAUPHIN/34 Amdt 1 - Main Rotor Pitch Change Horn Bushes","slug":"ad-dauphin-34-amdt-1-main-rotor-pitch-change-horn-bushes","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":52004,"registerId":"commonwealth-F2006B08745-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/DAUPHIN/34 Amdt 1 - Main Rotor Pitch Change Horn Bushes","content":"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n![](image.001.png)  \nEurocopter SA 360 and SA 365 (Dauphin) Series Helicopters\n\nAD/DAUPHIN/34\n\nAmdt 1\n\n  \nMain Rotor Pitch Change Horn Bushes 7/93\n\nDM\n\nApplicability: All models 365 fitted with pitch change horns P/N 365A31-1998-02 or P/N 350A31- 1877-02 that are not marked with an “X” after the part number, and have a serial number less than 100-000.\n\nRequirement: Action in accordance with Eurocopter SB 365C 65.31 R1 or SB 365N 62.11 R1 as applicable.\n\nNote: DGAC ADs 92-181-132(B)R1 and 92-182-036(B)R1 refer.\n\nCompliance: 1. Paragraph 1.C.1.: Within 50 hours time in service after 12 May 1993, and\n\n2. If required, para 1.C.2.b.: within 300 hours time in service after 12 May 1993\\. The effective date of the initial issue of this Directive was 12 November 1992.\n\nBackground: The initial issue of the Directive was due to the discovery of pitch change horn bushes that were incorrectly tapered and could possibly cause failure of the pitch change horn to rod connecting bolt. Amendment 1 revises Applicability to include all pitch change horn serial numbers to 100-000.","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":true,"description":"The original directive (issued 12 November 1992) had narrower applicability. Amendment 1 expands the scope to include 'all pitch change horn serial numbers to 100-000' — broadening the safety order to cover more aircraft than initially targeted. This represents a scope expansion based on new safety data revealing the manufacturing defect affected more units than originally identified."},"complexity_factors":["Short, single-purpose instrument (approximately 200 words)","Only 2 defined part numbers and 1 serial number threshold to interpret","Simple conditional structure: if the part matches criteria, do the action","Cross-references to 2 external Eurocopter Service Bulletins and 2 French DGAC Airworthiness Directives (but these are informational rather than operative)","Clear compliance deadlines with specific flight hour limits","No nested exceptions or complex definitional sections"],"plain_english_summary":"This AD mandates inspection or replacement of pitch change horn bushes on Eurocopter SA 360/365 Dauphin helicopters after bushes with an incorrect taper were found, risking connecting-bolt failure and loss of main-rotor control. It applies to parts 365A31-1998-02 or 350A31-1877-02 with serials below 100‑000 not marked “X.”\n\nOperators must follow the relevant Eurocopter Service Bulletins (first inspection within 50 flight hours of 12 May 1993; any required follow-up within 300 hours)."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"Amendment 1 broadened the directive's applicability: it now includes all pitch change horn serial numbers up to 100-000 (previous applicability was narrower). This expands the set of affected parts/operators required to comply (Background: \"Amendment 1 revises Applicability to include all pitch change horn serial numbers to 100-000\")."},"complexity_factors":["Applicability is part-number and serial-number specific (P/Ns 365A31-1998-02 or 350A31-1877-02; serials < 100-000) and excludes parts marked with an “X” — requires operators to identify parts at the component-serial level (Applicability).","Compliance times are short and tiered (within 50 hours TIS for para 1.C.1; up to 300 hours TIS for para 1.C.2.b) — creates operational scheduling and downtime considerations (Compliance).","Mandates following Eurocopter Service Bulletins (SB 365C 65.31 R1 or SB 365N 62.11 R1) rather than prescribing step-by-step actions in the AD — requires access to and reliance on manufacturer SBs (Requirement).","Safety-critical technical defect (incorrectly tapered bushes risking bolt failure) requires inspection/rectification by maintenance personnel with appropriate capability (Background).","Cross-references to DGAC ADs increase tracing work for regulatory compliance and record-keeping (Note)."],"plain_english_summary":"This airworthiness directive requires operators of Eurocopter SA 365 helicopters fitted with certain pitch change horns (P/N 365A31-1998-02 or 350A31-1877-02, serials below 100-000 and not marked “X”) to carry out inspections and corrective actions in accordance with Eurocopter service bulletins within specified flight‑hour limits. It responds to incorrectly tapered pitch change horn bushes that could allow a connecting bolt to fail, and imposes an operational compliance cost and maintenance action on affected operators."}},"importantCases":[],"_links":{"self":"/api/acts/ad-dauphin-34-amdt-1-main-rotor-pitch-change-horn-bushes","history":"/api/acts/ad-dauphin-34-amdt-1-main-rotor-pitch-change-horn-bushes/history","analysis":"/api/acts/ad-dauphin-34-amdt-1-main-rotor-pitch-change-horn-bushes/analysis","conflicts":"/api/acts/ad-dauphin-34-amdt-1-main-rotor-pitch-change-horn-bushes/conflicts","importantCases":"/api/acts/ad-dauphin-34-amdt-1-main-rotor-pitch-change-horn-bushes/important-cases","documents":"/api/acts/ad-dauphin-34-amdt-1-main-rotor-pitch-change-horn-bushes/documents"}}