{"id":"F2006B06953","name":"AD/SF340/24 - Wing and Stabilizer Rework and Reinforcements","slug":"ad-sf340-24-wing-and-stabilizer-rework-and-reinforcements","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":114851,"registerId":"commonwealth-F2006B06953-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/SF340/24 - Wing and Stabilizer Rework and Reinforcements","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)  SAAB SF340 Series Aeroplanes\n\n \n\nAD/SF340/24 Wing and Stabilizer Rework and Reinforcements 5/91\n\nApplicability: All Model SF340 with:\n\n \n\n1. Serial Nos SF340A -004 through -108 for Service Bulletin SAAB 340-57-017, and\n2.  Serial Nos SF340A -004 through -138 for Service Bulletin SAAB 340-55-027. Requirement:              Action in accordance with the technical requirements of Swedish Airworthiness\n\n\nDirective No 1-035 Revision A, issued 29 June 1990.\n\n \n\nNote: Service Bulletins: SAAB 340-55-027 and SAAB 340-57-017 refer.\n\n \n\nCompliance: Prior to exceeding 16000 flight cycles.\n\n \n\nBackground:  Full scale fatigue testing has indicated that the four referenced wing attach fastener holes, and the front and rear horizontal stabilizer spars are fatigue critical.\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 directive implements corrective structural work already prescribed by Swedish Airworthiness Directive No 1-035 Rev A and associated Saab service bulletins for specified SF340A serial numbers (Requirement; Note; Applicability). It does not expand applicability beyond the serial-number ranges identified nor alter the stated compliance threshold (Compliance), so it appears consistent with the original corrective intent rather than changing scope."},"complexity_factors":["External technical dependency: Action is required “in accordance with the technical requirements of Swedish Airworthiness Directive No 1-035 Revision A” — operators must obtain and follow another authority’s detailed instructions (Requirement).","Reference service bulletins: The AD refers to two Saab service bulletins (SAAB 340-55-027 and SAAB 340-57-017) for corrective work (Note).","Narrow applicability by serial number: Only SF340A serials -004 through -108 (one SB) and -004 through -138 (the other SB) are affected, so operators must verify serial-specific applicability before acting (Applicability).","Fixed compliance threshold: Work must be completed prior to exceeding 16,000 flight cycles, creating a clear scheduling and tracking obligation (Compliance).","Technical scope: Required work is structural rework and reinforcement of wing attach fastener holes and front/rear horizontal stabilizer spars — requires specialised maintenance capability, parts and engineering authority approval (Background & Requirement).","Operational burden: Owners/operators bear the cost, downtime and logistics of scheduling the modifications; maintenance planning and record-keeping are implied by the compliance and applicability requirements (Applicability; Compliance).","Regulatory clarity but limited discretion: The AD prescribes what to do and when (low regulator discretion) but leaves technical execution to the referenced documents and approved maintenance organisations (Requirement; Note)."],"plain_english_summary":"This Airworthiness Directive requires owners/operators of specific Saab SF340A aeroplanes (identified by serial numbers) to carry out wing attach and horizontal stabilizer rework and reinforcements. The mandated work must follow the technical requirements of Swedish Airworthiness Directive No 1-035 Revision A and related Saab service bulletins, and be completed before the aircraft exceed 16,000 flight cycles. It matters because fatigue testing identified those wing‑attach holes and stabilizer spars as fatigue‑critical, so the directive compels structural modification to address that risk."},"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This is a discrete, targeted airworthiness directive addressing specific fatigue-critical structural issues identified through testing. It has not expanded beyond its original purpose of mandating wing and stabilizer reinforcements for early-production SAAB SF340A aircraft."},"complexity_factors":["Single, specific technical requirement referencing an external Swedish directive rather than spelling out detailed procedures","Limited applicability — only affects two specific serial number ranges for two different service bulletins","Clear compliance deadline (16,000 flight cycles)","No nested exceptions or conditional logic — straightforward mandate","Minimal defined terms (only 'flight cycles' and serial number ranges need interpretation)","Short document length (approximately 200 words of substantive content)"],"plain_english_summary":"CASA mandates structural reinforcements to the wings and horizontal stabilizers of certain SAAB SF340A turboprops, following Swedish AD 1-035 Rev A. It affects specified serials (wings: SF340A‑004–108; stabilizers: SF340A‑004–138) because fatigue testing found bolt holes and spars are crack‑prone. Compliance is mandatory before 16,000 flight cycles or the aircraft cannot legally operate in Australia."}},"importantCases":[],"_links":{"self":"/api/acts/ad-sf340-24-wing-and-stabilizer-rework-and-reinforcements","history":"/api/acts/ad-sf340-24-wing-and-stabilizer-rework-and-reinforcements/history","analysis":"/api/acts/ad-sf340-24-wing-and-stabilizer-rework-and-reinforcements/analysis","conflicts":"/api/acts/ad-sf340-24-wing-and-stabilizer-rework-and-reinforcements/conflicts","importantCases":"/api/acts/ad-sf340-24-wing-and-stabilizer-rework-and-reinforcements/important-cases","documents":"/api/acts/ad-sf340-24-wing-and-stabilizer-rework-and-reinforcements/documents"}}