{"id":"F2006B09808","name":"AD/F28/74 - Control Column Aileron Chain - Replacement","slug":"ad-f28-74-control-column-aileron-chain-replacement","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":54730,"registerId":"commonwealth-F2006B09808-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/F28/74 - Control Column Aileron Chain - Replacement","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)  \nFokker F28 Series Aeroplanes\n\nAD/F28/74 Control Column Aileron Chain \\- Replacement 9/94\n\nApplicability: All F28 aircraft (except Mk 0100) S/N 11003 through 11241, 11991 and 11992.\n\nRequirement: Replace all control column aileron chains P/N KH-2212-AF-(X)21 with new units of the same part number, in accordance with Fokker Service Bulletin F28/27-181.\n\nNote: RLD AD 93-004(A) refers.\n\nCompliance: Replace all aileron chains before 01 March 1995.\n\nThis AD is effective from 18 August 1994.\n\nBackground: Two operators have reported incidents where the aileron chain in one of the control columns has failed, causing that pilot to lose aileron control. In both cases, investigation has shown the reason for the premature failure to be fatigue caused by improper initial adjustment of the flight control cables. As it is impossible after time to determine whether the cables on individual aircraft were installed correctly, a one- time replacement of all aileron chains is required to ensure continued safety of operation.","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, one-off safety directive with no indication of scope creep. It addresses exactly what it set out to address: replacement of a specific faulty component in a specific aircraft series."},"complexity_factors":["Very short document (under 200 words)","Only 1 defined term implicitly used (P/N = Part Number)","Single, unambiguous compliance requirement with clear deadline","No cross-references to other legislation (only references a manufacturer service bulletin and a related foreign directive)","No conditional logic or exceptions — applies to all listed serial numbers without qualification","Narrow, technical scope limited to one specific aircraft part"],"plain_english_summary":"This Airworthiness Directive orders owners/operators of specified Fokker F28 aircraft (S/N 11003–11241, 11991, 11992) to replace the control column aileron chain (KH-2212-AF-(X)21). Two in‑flight breaks from metal fatigue, traced to incorrect original cable installation, caused loss of aileron control; because installations can’t be reliably distinguished, all listed aircraft must comply per Fokker Service Bulletin F28/27-181 before 1 March 1995."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The AD limits its effect to a one‑time replacement of a specific part on listed F28 serial numbers and does not broaden ongoing maintenance obligations beyond that corrective action (Applicability; Requirement; Compliance). It implements a targeted remedial measure in response to reported failures and does not alter regulatory coverage for other aircraft or components."},"complexity_factors":["Narrow applicability tied to specific airframe serial numbers (Applicability)","Single, mandatory corrective action with a fixed compliance deadline (Compliance)","Technical specificity of the affected component (exact part number) and reliance on a manufacturer service bulletin for execution (Requirement)","No ongoing inspection regime—one‑time replacement only—reduces procedural complexity but concentrates implementation risk at the compliance date (Background/Requirement)","Reference to another directive (RLD AD 93-004(A)) introduces cross-document tracing for full regulatory context"],"plain_english_summary":"Requires operators of specified Fokker F28 aeroplanes (listed serial numbers, excluding Mk 0100) to replace all control‑column aileron chains (P/N KH-2212-AF-(X)21) with new units per Fokker Service Bulletin F28/27-181 by 1 March 1995. The directive follows two incidents of aileron‑chain fatigue traced to incorrect initial cable adjustment; because past installations cannot be reliably verified, a one‑time replacement is mandated to restore known configuration and reduce risk to flight controls."}},"importantCases":[],"_links":{"self":"/api/acts/ad-f28-74-control-column-aileron-chain-replacement","history":"/api/acts/ad-f28-74-control-column-aileron-chain-replacement/history","analysis":"/api/acts/ad-f28-74-control-column-aileron-chain-replacement/analysis","conflicts":"/api/acts/ad-f28-74-control-column-aileron-chain-replacement/conflicts","importantCases":"/api/acts/ad-f28-74-control-column-aileron-chain-replacement/important-cases","documents":"/api/acts/ad-f28-74-control-column-aileron-chain-replacement/documents"}}