{"id":"F2006B09793","name":"AD/F28/58 - Main Frame - Flap Track Beam Support Bracket at Wing Station 5280","slug":"ad-f28-58-main-frame-flap-track-beam-support-bracket-at-wing-station-5280","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":54713,"registerId":"commonwealth-F2006B09793-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/F28/58 - Main Frame - Flap Track Beam Support Bracket at Wing Station 5280","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 F28 Series Aeroplanes\n\n \n\n# AD/F28/58 Main Frame - Flap Track Beam Support\n\nBracket at Wing Station 5280 Applicability: F28 Serial Numbers 11003 to 11241 inclusive, 11991 and 11992. Requirement:               Action in accordance with Fokker SB F28-57-81.\n\nNote: RLD AD 88-030 refers.\n\n# 10/88\n\n \n\nCompliance: 1. For aircraft with less than 20 000 flight cycles or 10 000 flight hours total time in service - Before exceeding 20 000 flight cycles or 10 000 flight hours total time in service whichever comes first.\n\n \n\n2. For aircraft with more than 20 000 flight cycles or 10 000 flight hours total time in service at 6 October 1988 - within 500 flight cycles.\n\n \n\nBackground:  As a result of fuel leakage, a crack was revealed in the rear spar web at W.S. 5280, possibly initiated at an unauthorised spot face in the rear spar web. Also bolt holes have been found not perpendicular to the rear spar causing bolt seating deficiencies.\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":3,"scope_assessment":{"changed":false,"description":"This Airworthiness Directive maintains its original narrow scope — addressing a specific structural defect in a specific aircraft type. ADs are inherently limited-purpose instruments, and this one has not expanded beyond its original safety intent."},"complexity_factors":["Single, specific technical requirement referencing an external manufacturer document (Fokker SB F28-57-81)","Two-tier compliance schedule based on aircraft flight hours/cycles","Minimal defined terms (only standard aviation terminology like 'flight cycles' and 'wing station')","No nested exceptions or conditional logic beyond the basic applicability and compliance timing","Short document (approximately 200 words of substantive content)","Single cross-reference to related Dutch aviation authority directive (RLD AD 88-030)"],"plain_english_summary":"CASA requires owners/operators of specified Fokker F28 serials to inspect and repair the flap track beam support bracket at wing station 5280 because cracks from fuel leakage and manufacturing/misalignment defects threaten wing integrity. Affected aircraft must be repaired per Fokker Service Bulletin F28‑57‑81 within set flight‑cycle/flight‑hour windows (earlier of specified thresholds or within 500 cycles of 6 Oct 1988) — effectively a mandatory \"fix it or ground it\" order to prevent catastrophic structural failure."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The directive is narrowly targeted: it applies only to listed serial numbers and mandates actions per the specified Fokker service bulletin (Applicability; Requirement). It addresses a discrete defect (cracks and bolt seating issues revealed after fuel leakage) and imposes a one-off inspection/repair timetable (Compliance), rather than creating ongoing or expanded regulatory obligations."},"complexity_factors":["Limited applicability to a defined set of serial numbers creates a narrow but technical scope (Applicability).","Requires operators to follow an external document (Fokker SB F28-57-81), creating dependency on that service bulletin (Requirement).","Two-tier compliance schedule tied to flight cycles and flight hours with a different deadline for aircraft already past thresholds (Compliance: 1 & 2).","Technical inspection and corrective work on a structural main frame location (wing station 5280) implies skilled maintenance, possible parts/repairs and aircraft downtime (Background & Requirement).","Reference to a related airworthiness directive (RLD AD 88-030) adds cross-document traceability for maintainers."],"plain_english_summary":"This airworthiness directive tells operators of certain Fokker F28 aeroplanes (serial numbers 11003–11241, 11991–11992) to carry out the inspections and corrective work specified in Fokker Service Bulletin F28-57-81 on the main frame flap-track beam support at wing station 5280. It requires completion before the aeroplane exceeds 20,000 flight cycles or 10,000 flight hours, or within 500 flight cycles if already above those thresholds as at 6 October 1988, to address discovered cracks and bolt seating defects."}},"importantCases":[],"_links":{"self":"/api/acts/ad-f28-58-main-frame-flap-track-beam-support-bracket-at-wing-station-5280","history":"/api/acts/ad-f28-58-main-frame-flap-track-beam-support-bracket-at-wing-station-5280/history","analysis":"/api/acts/ad-f28-58-main-frame-flap-track-beam-support-bracket-at-wing-station-5280/analysis","conflicts":"/api/acts/ad-f28-58-main-frame-flap-track-beam-support-bracket-at-wing-station-5280/conflicts","importantCases":"/api/acts/ad-f28-58-main-frame-flap-track-beam-support-bracket-at-wing-station-5280/important-cases","documents":"/api/acts/ad-f28-58-main-frame-flap-track-beam-support-bracket-at-wing-station-5280/documents"}}