{"id":"F2006B06977","name":"AD/SF340/48 - Rudder Nose Rib","slug":"ad-sf340-48-rudder-nose-rib","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":114892,"registerId":"commonwealth-F2006B06977-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/SF340/48 - Rudder Nose Rib","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/SF340/48 Rudder Nose Rib 13/95\n\nApplicability: Model SF 340A with serial numbers 004 through 159.\n\n \n\nModel 340B with serial numbers 160 through 369.\n\n \n\nRequirement: Action in accordance with SAAB Service Bulletin 340-55-032.\n\n \n\nNote: LFV AD 1-074 refers.\n\n \n\nCompliance: As specified in the Requirement Document with a revised effective date of 7 December 1995.\n\n \n\nBackground: A report was received of a cracked nose rib on the front spar of the rudder. This condition could result in jamming between the fin and rudder due to deformation of the cracked nose rib web.\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":2,"scope_assessment":{"changed":false,"description":"The document defines a focused corrective requirement for a specific defect on clearly identified aircraft serial numbers. The text contains no indication that the scope has been altered from its original intent; it directs compliance with a named service bulletin and specifies the effective compliance date (Requirement; Compliance; Applicability)."},"complexity_factors":["Narrow, specific applicability (limited serial-number ranges) reduces scope complexity (Applicability).","Core action is delegated to an external technical document (SAAB Service Bulletin 340-55-032), so the AD itself is short but depends on an outside document for procedural detail (Requirement).","Compliance timing is set by the Requirement Document with a specific revised effective date, creating a dependency on that document for enforcement windows (Compliance).","Cross-reference to another authority’s AD (LFV AD 1-074) adds a minor coordination factor (Note).","The AD states the safety consequence (cracked nose rib may cause jamming) but provides no cost, penalty, or approval detail, requiring implementers to consult additional sources for full operational impact (Background and overall silence on costs)."],"plain_english_summary":"This Airworthiness Directive (AD) requires operators of certain Saab SF340 aeroplanes to carry out maintenance actions described in a Saab service bulletin to address a specific structural problem.\n\n- What it does mechanically: It directs that affected aircraft be inspected and/or repaired in accordance with SAAB Service Bulletin 340-55-032 (\"Requirement\"). Compliance must follow the timings and steps set out in that Requirement Document, with a revised effective date of 7 December 1995 (\"Compliance\").\n\n- Who it applies to: Model SF 340A with serial numbers 004–159, and Model 340B with serial numbers 160–369 (\"Applicability\").\n\n- Why it was issued: A report identified a cracked nose rib on the front spar of the rudder. The cracked nose rib web can deform and could cause jamming between the fin and rudder (\"Background\"). The AD therefore directs the specified corrective actions in the Saab service bulletin to address that condition.\n\n- How it works in practice: The Civil Aviation Safety Authority publishes the AD and requires operators of the listed serial-numbered aircraft to implement the actions set out in the referenced service bulletin. The AD itself does not list the step‑by‑step technical procedures; it delegates those details to the service bulletin (\"Requirement\"). Compliance timing is governed by the Requirement Document (\"Compliance\"). The AD also notes a related foreign AD (LFV AD 1-074) (\"Note\").\n\n- Who pays and who decides: The instrument requires the specified maintenance actions but does not state who bears the costs or the source of funding. The AD is the regulatory direction; the technical content and procedures are in the Saab service bulletin cited in the Requirement.\n\n- Compliance burden and discretion: Operators must follow the service bulletin to comply. The AD delegates technical specification to the manufacturer’s service bulletin, so the AD enforces compliance with that external document rather than prescribing detailed techniques itself. The AD does not specify penalties, approvals, or cost allocations.\n\n- Risk and trade-offs stated in the source: The background identifies the safety risk if the defect is not corrected (possible jamming of fin and rudder). The AD therefore imposes an operational cost on affected-aircraft operators to carry out the required inspections/repairs; the document does not quantify those costs or alternative mitigations.\n\nSections cited: Applicability; Requirement; Compliance; Note; Background."},"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 type. It has not expanded beyond its original purpose of mandating inspection/repair of the rudder nose rib."},"complexity_factors":["Extremely short document (under 200 words)","Only 2 defined applicability criteria (serial number ranges)","Single requirement referencing an external technical document (SAAB Service Bulletin)","No nested exceptions, conditional logic, or cross-references to other legislation","Straightforward compliance deadline structure","Minimal legal drafting — essentially a safety notice with legal force"],"plain_english_summary":"This is an **Airworthiness Directive** (AD) — essentially a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA). It requires owners and operators of specific **SAAB SF340 aircraft** to inspect and repair a potential defect in the rudder.\n\n**What the problem is:**\nThe front part of the rudder (called the \"nose rib\") can crack where it attaches to the front spar. If this crack worsens, the damaged metal can bend and jam between the rudder and the vertical fin — potentially causing the rudder to seize up during flight.\n\n**Who must act:**\n- Owners of **SF 340A** models with serial numbers 004–159\n- Owners of **SF 340B** models with serial numbers 160–369\n\n**What they must do:**\nFollow the instructions in **SAAB Service Bulletin 340-55-032** — a technical repair guide from the manufacturer. The directive references a Swedish aviation authority notice (LFV AD 1-074) for additional context.\n\n**When:**\nBy the deadlines set out in that Service Bulletin, with a hard deadline of **7 December 1995**.\n\n**Why it matters:**\nThis is a **flight safety issue**. A jammed rudder could make the aircraft difficult or impossible to control, especially during landing or in crosswinds. The AD makes compliance legally mandatory — ignoring it grounds the aircraft."}},"importantCases":[],"_links":{"self":"/api/acts/ad-sf340-48-rudder-nose-rib","history":"/api/acts/ad-sf340-48-rudder-nose-rib/history","analysis":"/api/acts/ad-sf340-48-rudder-nose-rib/analysis","conflicts":"/api/acts/ad-sf340-48-rudder-nose-rib/conflicts","importantCases":"/api/acts/ad-sf340-48-rudder-nose-rib/important-cases","documents":"/api/acts/ad-sf340-48-rudder-nose-rib/documents"}}