{"id":"F2006B09890","name":"AD/F50/61 - Aileron Trim Screwjack Capscrews","slug":"ad-f50-61-aileron-trim-screwjack-capscrews","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":55034,"registerId":"commonwealth-F2006B09890-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/F50/61 - Aileron Trim Screwjack Capscrews","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/F50/61 Aileron Trim Screwjack Capscrews 8/93\n\nApplicability: Model F27 Mk 050, all serial numbers, if equipped with Morse Controls Ltd. Aileron Trim Screwjacks, P/N 189255, serial numbers 53/88 through 112/90.\n\n \n\nRequirement: Action in accordance with the technical requirements of RLD AD 93-066 (A).\n\n \n\nNote: Fokker SB F50-27-038 and Morse Controls Ltd SB 27-10-189255-A Issue 1 refer.\n\n \n\nCompliance: As specified in the Requirement Document.\n\n \n\nBackground: A number of failed capscrews have been detected during a shop inspection. Subsequent investigation showed that these failures were due to an incorrect treatment. Failure of all capscrews could result in uncontrolled movement of the trim/balance tab, i.e. flutter.\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":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, targeted safety directive addressing a specific mechanical defect in a specific aircraft component. It has not expanded beyond its original purpose of mandating inspection/replacement of faulty capscrews."},"complexity_factors":["Very short document (under 200 words)","Only 1 defined applicability criterion (specific part numbers and serial numbers)","Single requirement: comply with external technical document (RLD AD 93-066 (A))","No nested exceptions or conditional logic","No internal cross-references to other sections of Australian legislation","References to 2 service bulletins for information only (non-binding)"],"plain_english_summary":"This AD mandates inspection and, if necessary, replacement of capscrews in the aileron trim screwjack on certain Fokker F50s (S/N 53/88–112/90) equipped with Morse Controls P/N 189255. Incorrect heat treatment of these capscrews can lead to cracking and uncontrolled trim/tab movement that may cause flutter. Operators must comply with RLD AD 93-066 (A) per its specified deadlines."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"Scope remains focused on F27 Mk 050 aeroplanes fitted with the specified Morse Controls aileron trim screwjack part/serial numbers and directs compliance with RLD AD 93-066 (A). The AD does not expand beyond those aircraft/parts or alter the stated safety objective (see Applicability; Requirement; Background)."},"complexity_factors":["Narrow technical applicability to specific aircraft model and part/serial number range (Applicability: Model F27 Mk 050 ... P/N 189255, serial numbers 53/88 through 112/90).","Mandates actions by reference to an external technical directive (Requirement: Action in accordance with the technical requirements of RLD AD 93-066 (A)), so the detailed steps are not in this text.","Safety-critical mechanical failure mode (capscrew failure due to incorrect treatment) requires maintenance/inspection work by qualified organisations (Background: failed capscrews ... incorrect treatment; could result in uncontrolled movement i.e. flutter).","Operational compliance burden rests on operators/maintenance organisations to locate affected units and implement the referenced corrective actions (Compliance: As specified in the Requirement Document).","Potential ambiguity on timing and exact procedures for compliance because those details are delegated to the referenced Requirement Document rather than stated here."],"plain_english_summary":"Requires operators of Fokker F50 (F27 Mk 050) aeroplanes fitted with Morse Controls aileron trim screwjacks (P/N 189255, S/N 53/88–112/90) to carry out the corrective actions specified in RLD AD 93-066 (A). It responds to detected capscrew failures caused by incorrect treatment; failure could allow uncontrolled trim/balance-tab movement (flutter). This matters to aircraft owners and maintenance organisations because it mandates inspection/rectification to prevent a flight‑safety hazard."}},"importantCases":[],"_links":{"self":"/api/acts/ad-f50-61-aileron-trim-screwjack-capscrews","history":"/api/acts/ad-f50-61-aileron-trim-screwjack-capscrews/history","analysis":"/api/acts/ad-f50-61-aileron-trim-screwjack-capscrews/analysis","conflicts":"/api/acts/ad-f50-61-aileron-trim-screwjack-capscrews/conflicts","importantCases":"/api/acts/ad-f50-61-aileron-trim-screwjack-capscrews/important-cases","documents":"/api/acts/ad-f50-61-aileron-trim-screwjack-capscrews/documents"}}