{"id":"F2006B07620","name":"AD/Y12/6 - Control Wheel Pulley Bearing","slug":"ad-y12-6-control-wheel-pulley-bearing","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":50338,"registerId":"commonwealth-F2006B07620-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"AIRWORTHINESS DIRECTIVE","sectionType":"part","heading":"AIRWORTHINESS DIRECTIVE","content":"# AIRWORTHINESS DIRECTIVE\n\n![](image.001.png)\n\n![](image.001.png)  \nFor the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (AD) under subregulation 39.1 (1) of CAR 1998. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.\n\nHarbin Y12 Series Aeroplanes","sortOrder":0},{"sectionNumber":"AD/Y12/6 Control Wheel Pulley Bearing 3/","sectionType":"part","heading":"AD/Y12/6 Control Wheel Pulley Bearing 3/2003","content":"# AD/Y12/6 Control Wheel Pulley Bearing 3/2003\n\nApplicability: Y12II aircraft with Serial Numbers (S/N) 3812 (024), 3813 (025), 3814 (026), 3816\n\n(028), and 3817 (029).\n\nRequirement: 1. Check the Part Number (P/N) of the control wheel pulley bearing installed is P/N 980067.\n\n2. Replace the control wheel pulley bearings where the bearings are not P/N 980067.\n\nNote: China CAAC AD CAD89-53-Y12.0003-27 refers.\n\nCompliance: 1. Unless previously accomplished prior to further flight.\n\n2. Prior to further flight.\n\nThis Airworthiness Directive becomes effective on 20 March 2003.\n\nBackground: The wrong bearing was fitted to the control wheel pulley during manufacture which could lead to control wheel buffet.\n\n![Signature of James Coyne Delegate of the Civil Aviation Safety Authority](image.002.png)  \n\nJames Coyne\n\nDelegate of the Civil Aviation Safety Authority 30 January 2003\n\n![](image.001.png)  \n\nThe above AD is notified in the Commonwealth of Australia Gazette on 26 February 2003.","sortOrder":1}],"analysis":{"flash_summary_failed":{"failed":true,"reason":"A positive credit balance is required for all requests, including BYOK, so fallback providers remain available. Add credits at https://vercel.com/d?to=%2F%5Bteam%5D%2F%7E%2Fai%3Fmodal%3Dtop-up to continue.","source":"analysis-cron"},"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The AD's scope matches the stated intent in the instrument: it targets a manufacturing error on the listed Y12II serial numbers and requires replacement with P/N 980067 before further flight (Applicability; Requirement; Compliance). No broader applicability or additional obligations are introduced."},"complexity_factors":["Narrow applicability: only five serial numbers listed (Applicability).","Single, discrete technical check and fix: verify P/N and replace if necessary (Requirement 1–2).","Immediate operational impact: replacement required prior to further flight, which can ground aircraft until compliance (Compliance).","Low regulatory discretion: AD prescribes a specific part number (P/N 980067) rather than performance-based outcome (Requirement).","Clear causal statement linking wrong part to unsafe condition reduces interpretive complexity (Background).","Supply risk: operators depend on availability of the specified bearing part (implicit in Requirement).","Cross-reference to foreign authority (China CAAC AD) may require consulting external documentation (Note).","Recordkeeping and proof of compliance expected though not elaborated in AD (Compliance implied)."],"plain_english_summary":"This AD applies to Harbin Y12II aircraft S/N 3812, 3813, 3814, 3816 and 3817. It requires inspecting the control‑wheel pulley bearing part number and replacing any bearing that is not P/N 980067 before the aircraft next flies, because a wrongly fitted bearing could cause control‑wheel buffet. \n\nCASA says the directive corrects a manufacturing error; operators must pay for parts and labour and may face temporary grounding until replacement is done."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This AD maintains its original narrow scope. It targets a specific manufacturing defect in a specific component on specific aircraft. There is no evidence of scope creep — the directive does not expand to cover other aircraft types, other bearing types, or broader operational requirements beyond the immediate safety fix."},"complexity_factors":["Very short document (under 300 words)","Only 5 specific aircraft affected by serial number","Single, straightforward mechanical check and replacement task","No defined terms section or interpretation provisions","No cross-references to other legislation (only a reference to a Chinese aviation authority document for context)","Simple binary compliance: check part number, replace if wrong","Immediate compliance requirement with no phased implementation"],"plain_english_summary":"This CASA Airworthiness Directive requires owners/operators of five Harbin Y12II aircraft (S/N 3812, 3813, 3814, 3816, 3817) to inspect the control wheel pulley bearing and ensure it is part number P/N 980067, replacing it if not. Action must be taken immediately, before the next flight, to eliminate a wrong bearing that can cause control‑wheel buffet and degrade safe handling."}},"importantCases":[],"_links":{"self":"/api/acts/ad-y12-6-control-wheel-pulley-bearing","history":"/api/acts/ad-y12-6-control-wheel-pulley-bearing/history","analysis":"/api/acts/ad-y12-6-control-wheel-pulley-bearing/analysis","conflicts":"/api/acts/ad-y12-6-control-wheel-pulley-bearing/conflicts","importantCases":"/api/acts/ad-y12-6-control-wheel-pulley-bearing/important-cases","documents":"/api/acts/ad-y12-6-control-wheel-pulley-bearing/documents"}}