{"id":"F2006B09836","name":"AD/F50/11 - Wing Centre Section Cable Tray Blanking Plate","slug":"ad-f50-11-wing-centre-section-cable-tray-blanking-plate","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":54871,"registerId":"commonwealth-F2006B09836-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/F50/11 - Wing Centre Section Cable Tray Blanking Plate","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)  Fokker F50 (F27 Mk 50) Series Aeroplanes\n\n \n\nAD/F50/11 Wing Centre Section Cable Tray Blanking Plate 3/89\n\nDM\n\n \n\nApplicability: F27-050 S/Nos 20103 to 20108 and 20110 to 20129. Requirement:  Action in accordance with Fokker SB F50-57-003.\n\nNote: RLD AD 88-95 refers.\n\n \n\nCompliance: Prior to 31 March 1989.\n\n \n\nBackground:  Freezing of the cable system has occurred at high altitude, rain, high humidity and low OAT were factors. Installation of this blanking plate will prevent water ingress to this area.\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 in this text, is limited to installing the blanking plate on a defined set of F27-050 serial numbers to prevent water ingress and resultant freezing (Applicability; Requirement; Background). The document contains no language indicating an expansion or narrowing of that scope from an earlier or original intent; it prescribes the technical remedy and a compliance date without altering the target population."},"complexity_factors":["Narrow, clearly defined applicability by serial number (reduces scope complexity) (Applicability).","Mandated action refers to an external service bulletin for technical steps, creating dependency on another document (Requirement: Fokker SB F50-57-003).","Firm compliance deadline imposes scheduling and operational constraints on operators (Compliance: prior to 31 March 1989).","Stated background causal factors are environmental and technical but the AD prescribes a single corrective measure (Background).","Reference to a prior AD (RLD AD 88-95) introduces a regulatory linkage that may require cross-checking (Note)."],"plain_english_summary":"The rule mandates installation of a wing centre section cable tray blanking plate on specific Fokker F50 (F27 Mk 50) aeroplanes (listed serial numbers) by 31 March 1989, per Fokker Service Bulletin F50-57-003. It targets owners/operators of those aircraft to prevent water ingress and cable freezing under high-altitude, wet, cold conditions. The AD prescribes the corrective measure while delegating technical steps to the service bulletin; costs and scheduling burdens fall to affected operators."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, time-bound safety directive for a specific aircraft type and defect. It has not expanded beyond its original purpose of mandating a single physical modification to prevent cable freezing."},"complexity_factors":["Very short document (under 200 words)","Only one substantive requirement (install blanking plate per manufacturer bulletin)","Simple applicability clause (specific serial number ranges)","Single compliance deadline with no conditional extensions","No defined terms section, no cross-references to other legislation beyond a note about a related Dutch directive","Straightforward factual background with no legal exceptions or nested conditions"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** — essentially a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA) for specific aircraft.\n\n**What it does:**\nOrders owners/operators of certain Fokker F50 aeroplanes to install a blanking plate (a protective cover) on the wing centre section cable tray. This plate stops water getting into the cable system.\n\n**Why it matters:**\nWater had been getting into the cable system and freezing at high altitude, particularly in cold, wet, humid conditions. Frozen cables can jam or malfunction — a serious flight safety risk. This fix prevents that happening.\n\n**Who must comply:**\nAnyone operating Fokker F50 aircraft with serial numbers 20103-20108 and 20110-20129. They had to complete this modification before 31 March 1989.\n\n**How to comply:**\nFollow the instructions in Fokker Service Bulletin F50-57-003 (the manufacturer's official repair notice)."}},"importantCases":[],"_links":{"self":"/api/acts/ad-f50-11-wing-centre-section-cable-tray-blanking-plate","history":"/api/acts/ad-f50-11-wing-centre-section-cable-tray-blanking-plate/history","analysis":"/api/acts/ad-f50-11-wing-centre-section-cable-tray-blanking-plate/analysis","conflicts":"/api/acts/ad-f50-11-wing-centre-section-cable-tray-blanking-plate/conflicts","importantCases":"/api/acts/ad-f50-11-wing-centre-section-cable-tray-blanking-plate/important-cases","documents":"/api/acts/ad-f50-11-wing-centre-section-cable-tray-blanking-plate/documents"}}