{"id":"F2006L01342","name":"AD/AS 355/86 Amdt 1 - Tail Rotor Controls","slug":"ad-as-355-86-amdt-1-tail-rotor-controls","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":58858,"registerId":"commonwealth-F2006L01342-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Eurocopter AS 355 (Twin Ecureuil) Series","sectionType":"division","heading":"Eurocopter AS 355 (Twin Ecureuil) Series Helicopters","content":"### Eurocopter AS 355 (Twin Ecureuil) Series Helicopters\n\n| AD/AS 355/86 Amdt 1 | Tail Rotor Controls | 6/2006 |\n| ------------------- | ------------------- | ------ |\n\n| Applicability: | Model AS 355 E, F, F1, F2 and N, helicopters fitted with stainless steel-caged ball-type yaw controls pre-MOD 072771, part numbers:- 704A 34-130-068 for helicopters with automatic flight control system (AFCS), but with collective-to-yaw control coupling,- 704A 34-130-086 for helicopters without AFCS, and without collective-to-yaw control coupling.                                                                                                                                                                                                    |\n| -------------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | 1. Unless previously accomplished, remove the stainless steel-caged ball-type control and install the new Teflon-caged ball-type control in accordance with instructions specified in Paragraph 2 of the referenced ASB.2. Do not install on the helicopter any stainless steel cage ball type yaw controls as identified in the Applicability section of this Directive.Reference Document: EUROCOPTER AS 355 Alert Service Bulletin (ASB)No. 67.00.26 R2 or subsequent EASA approved revision.Note: EASA AD 2006-081 refers and supersedes DGAC AD F-2005-043. |\n| Compliance:    | 1. Within 30 days of the effective date of this AD.2. From the effective date of this Directive.                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |\n|                | This Amendment becomes effective on 8 June 2006.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                 |\n| Background:    | This Airworthiness Directive was issued following multiple cases of binding discovered in the stainless steel-caged ball-type yaw controls which may generate increased control loads or a feeling of seizure at the pedal units.This amendment changes applicability with no change to the requirement.                                                                                                                                                                                                                                                         |\n\n|     | The original issue of this AD became effective 9 June 2005. |\n| --- | ----------------------------------------------------------- |\n\n![](image.001.png)  \nJames Coyne  \nDelegate of the Civil Aviation Safety Authority\n\n28 April 2006","sortOrder":0},{"sectionNumber":"AD/AS 355/86 Amdt 1","sectionType":"part","heading":"AD/AS 355/86 Amdt 1","content":"## AD/AS 355/86 Amdt 1","sortOrder":1},{"sectionNumber":"Tail Rotor Controls","sectionType":"part","heading":"Tail Rotor Controls","content":"## Tail Rotor Controls","sortOrder":2},{"sectionNumber":"6/2006","sectionType":"part","heading":"6/2006","content":"## 6/2006","sortOrder":3}],"analysis":{"flash_summary_failed":{"failed":true,"reason":"Unauthenticated. Configure AI_GATEWAY_API_KEY or use a provider module. Learn more: https://ai-sdk.dev/unauthenticated-ai-gateway","source":"analysis-cron"},"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":true,"description":"The amendment revised the applicability (which helicopters/parts are covered) but did not change the substantive requirement to replace stainless steel‑caged ball‑type yaw controls with Teflon‑caged units (Background). The amendment sets an effective date of 8 June 2006; the original AD first became effective 9 June 2005."},"complexity_factors":["Narrow applicability: specific AS 355 models and particular part numbers (pre‑MOD 072771) limit affected fleet but require accurate parts identification.","Single clear action: mandatory removal and replacement with a specified part reduces procedural ambiguity.","Short compliance window: 30‑day deadline can compress maintenance scheduling and parts sourcing.","Prohibition on reinstalling old parts increases ongoing compliance and recordkeeping obligations.","Dependence on manufacturer service instructions: compliance requires following Eurocopter ASB No. 67.00.26 R2 (or later) and any EASA‑approved revisions.","Enforcement by regulator (CASA) creates legal/operational consequences for non‑compliance."],"plain_english_summary":"This Airworthiness Directive requires owners/operators of Eurocopter AS 355 E, F, F1, F2 and N helicopters fitted with specified stainless steel‑caged ball‑type tail (yaw) controls to remove them and install Teflon‑caged replacements per Eurocopter ASB No. 67.00.26 R2 (or later) within 30 days and prohibits reinstalling the stainless‑steel parts.\n\nIt was issued after multiple cases of binding in the steel cages that increased control loads; operators pay for parts and maintenance, and the Civil Aviation Safety Authority enforces compliance."},"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This is an amendment that explicitly states it changes only the applicability (which helicopters are covered) with no change to the actual safety requirement. The scope remains tightly focused on the original safety issue: replacing faulty tail rotor yaw controls."},"complexity_factors":["Multiple specific part numbers and model variants in applicability (AS 355 E, F, F1, F2, N)","Conditional applicability based on presence/absence of automatic flight control system (AFCS) and collective-to-yaw coupling","Reference to external technical document (Eurocopter ASB 67.00.26 R2) for actual implementation instructions","Cross-reference to European aviation safety regulations (EASA AD 2006-081 and superseded DGAC AD)","Two separate compliance deadlines for different requirements (removal vs. prohibition on installation)","Amendment structure requires understanding of what changed from original AD (applicability only)"],"plain_english_summary":"This CASA Airworthiness Directive orders owners/operators of certain Eurocopter AS355 E/F/F1/F2/N helicopters (those without MOD 072771) to replace stainless‑steel‑caged ball bearings in the tail‑rotor yaw controls with Teflon‑caged bearings within 30 days of 8 June 2006. The steel bearings can bind or seize, risking loss of directional control; removed steel parts must not be reinstalled. This revision only updates applicability."}},"importantCases":[],"_links":{"self":"/api/acts/ad-as-355-86-amdt-1-tail-rotor-controls","history":"/api/acts/ad-as-355-86-amdt-1-tail-rotor-controls/history","analysis":"/api/acts/ad-as-355-86-amdt-1-tail-rotor-controls/analysis","conflicts":"/api/acts/ad-as-355-86-amdt-1-tail-rotor-controls/conflicts","importantCases":"/api/acts/ad-as-355-86-amdt-1-tail-rotor-controls/important-cases","documents":"/api/acts/ad-as-355-86-amdt-1-tail-rotor-controls/documents"}}