{"id":"F2006B06982","name":"AD/SF340/53 - Anti-Skid Drive Coupling","slug":"ad-sf340-53-anti-skid-drive-coupling","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":114900,"registerId":"commonwealth-F2006B06982-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/SF340/53 - Anti-Skid Drive Coupling","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/SF340/53 Anti-Skid Drive Coupling  5/96 DM\n\nApplicability: All SAAB SF340A S/N 004 through 159 and SF340B S/N 160 through 378 aircraft. Requirement:               Unless previously carried out, action in accordance with SAAB Service Bulletin 340-\n\n32-107 dated 18 January 1996.\n\n \n\nNote: Swedish AD No 1-085 R1 refers.\n\n \n\nCompliance: Prior to 30 April 1996.\n\n \n\nBackground: The manufacturer has advised that numerous occurrences of unexpected brake pressure reductions have been reported. In one incident an aircraft ran into an airport building.\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":{"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 specific aircraft. It has not expanded beyond its original purpose of mandating a safety fix for the anti-skid drive coupling issue."},"complexity_factors":["Very short document (approximately 150 words)","Only 2 defined applicability criteria (aircraft serial number ranges)","Single, unambiguous compliance requirement (follow the service bulletin)","One simple deadline (prior to 30 April 1996)","No cross-references to other legislation beyond a note about a Swedish AD","No conditional logic or exceptions — straightforward 'unless already done, do this' structure","No interpretation section or defined terms"],"plain_english_summary":"**What this is:** This is an **Airworthiness Directive (AD)** — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA). Think of it as a \"recall notice\" for aircraft, but legally binding.\n\n**What it does:** It requires owners and operators of specific SAAB SF340 aircraft to carry out a safety fix detailed in a manufacturer service bulletin (SB 340-32-107). The fix addresses a problem with the **anti-skid drive coupling** — a component that helps prevent wheels from locking up during braking.\n\n**Who it affects:** \n- All SAAB SF340A aircraft with serial numbers 004 through 159\n- All SAAB SF340B aircraft with serial numbers 160 through 378\n\n**Why it matters:** The manufacturer reported multiple incidents where brake pressure dropped unexpectedly. In one case, an aircraft crashed into an airport building. This directive forces operators to fix the defect before a deadline (30 April 1996) to prevent accidents.\n\n**Key requirement:** Unless the fix was already done, operators must follow the manufacturer's instructions in the specified service bulletin.\n\n**Note:** This references a Swedish airworthiness directive, showing international coordination on this safety issue."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The AD’s scope is explicitly set out in the instrument: it applies to defined serial number ranges of SAAB SF340A and SF340B aircraft, requires compliance with SAAB Service Bulletin 340-32-107 (18 January 1996), and sets a compliance date of prior to 30 April 1996. There is no material indication in the text that the AD’s scope departs from its stated purpose of addressing reported unexpected brake pressure reductions; therefore the scope has not changed from the instrument’s own stated intent. (Applicability / Requirement / Compliance / Background)"},"complexity_factors":["Narrow and explicit applicability by aircraft model and serial number ranges (clear scope). (Applicability)","Technical method delegated to a manufacturer Service Bulletin rather than detailed in the AD (requires consulting another document). (Requirement)","Fixed and near‑term compliance deadline imposing scheduling pressure. (Compliance)","Reference to an external foreign AD (Swedish AD No 1-085 R1) introduces cross-jurisdictional linkage. (Note)","Enforcement under Civil Aviation Regulations creates legal mandatory effect despite technical delegation. (Part 39 / Requirement)","Operational complexity for operators: parts availability, qualified maintenance labour and aircraft downtime affect implementation though not specified in the AD. (Requirement / Compliance)"],"plain_english_summary":"What this instrument does mechanically:\n\n- Applicability: It applies to all SAAB SF340A aircraft with serial numbers 004 through 159 and all SF340B aircraft with serial numbers 160 through 378. (Applicability)\n- Required action: Operators must carry out the work described in SAAB Service Bulletin 340-32-107 dated 18 January 1996. The AD does not itself set out the technical steps; it makes compliance with that Service Bulletin mandatory. (Requirement)\n- Deadline: The required work must be completed prior to 30 April 1996. (Compliance)\n- Regulatory basis: This requirement is issued under the Civil Aviation Regulations 1998, Part 39 - Schedule of Airworthiness Directives and is linked to a Swedish airworthiness directive (Swedish AD No 1-085 R1). (Note / Background)\n\nWhy the AD was issued (source statement):\n\n- The manufacturer reported numerous occurrences of unexpected brake pressure reductions, and one incident in which an aircraft ran into an airport building. The AD cites those reports as the reason for mandating the Service Bulletin action. (Background)\n\nWho pays, who decides, and what changes in behaviour:\n\n- Who pays: Operators of the affected SAAB SF340 aircraft will bear the direct costs of performing the mandatory work (parts, labour, aircraft downtime). (Applicability / Requirement)\n- Who decides: The Civil Aviation Safety Authority enforces the AD under the Civil Aviation Regulations; the manufacturer specifies the technical method via the Service Bulletin. (Requirement)\n- Behavioural change required: Operators must schedule and complete the Service Bulletin work on affected aircraft before the stated deadline; until they comply they remain non‑compliant with the AD and are subject to regulatory enforcement. (Compliance / Requirement)\n\nCosts, incentives, trade-offs and practical implementation points:\n\n- Incentives: Complying reduces the risk of further brake pressure reductions and related accidents, per the manufacturer’s reports. (Background)\n- Direct costs and compliance burden: The AD imposes maintenance costs, labour time and aircraft downtime on a defined set of operators. The exact technical and parts costs are set out only in the referenced Service Bulletin, not in the AD itself. (Requirement)\n- Implementation risk and operational impact: The fixed compliance date creates scheduling pressure; if parts, qualified maintenance personnel, or workshop capacity are limited, operators may face operational disruption. (Compliance / Requirement)\n- Administrative discretion: The AD prescribes compliance with the manufacturer’s Service Bulletin; discretionary decisions about timing, allocation of maintenance resources, and whether an operator grounds aircraft until work is done rest with operators and enforcement authorities. (Requirement / Compliance)\n- Cross‑jurisdictional note: The AD refers to a Swedish AD, indicating coordination with the State of Design’s regulatory action; the technical remediation is delegated to the manufacturer’s Service Bulletin. (Note)\n\nNet operational effect (mechanical summary): Operators of the specified SAAB SF340 serial numbers must implement the manufacturer’s corrective actions for the anti‑skid drive coupling by the deadline, or remain non‑compliant with the Civil Aviation Regulations. The stated motive is to address reported unintended brake pressure reductions to reduce the risk of similar incidents. (Applicability / Requirement / Background)"}},"importantCases":[],"_links":{"self":"/api/acts/ad-sf340-53-anti-skid-drive-coupling","history":"/api/acts/ad-sf340-53-anti-skid-drive-coupling/history","analysis":"/api/acts/ad-sf340-53-anti-skid-drive-coupling/analysis","conflicts":"/api/acts/ad-sf340-53-anti-skid-drive-coupling/conflicts","importantCases":"/api/acts/ad-sf340-53-anti-skid-drive-coupling/important-cases","documents":"/api/acts/ad-sf340-53-anti-skid-drive-coupling/documents"}}