{"id":"F2006B06963","name":"AD/SF340/34 - Dual Pressure Indicator","slug":"ad-sf340-34-dual-pressure-indicator","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":114864,"registerId":"commonwealth-F2006B06963-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/SF340/34 - Dual Pressure Indicator","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/SF340/34 Dual Pressure Indicator 7/92\n\nApplicability: All model SF340A serial number 003 to 138 inclusive.\n\n \n\nRequirement: Unless previously carried out action in accordance with SAAB-Scania Service Bulletin SF340-29-004 Revision 1.\n\n \n\nNote 1: Swedish AD SAD No 1-043 refers.\n\n \n\nNote 2: FAA AD 92-07-01 amdt 39-8197 refers.\n\n \n\nCompliance: By 30 June 1993.\n\n \n\nBackground: Reports of aircraft suffering loss of hydraulic pressure, which was not detected by the pilots, have been received. This has resulted in several aircraft taxiing with nose wheel steering and brakes inoperative.\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, time-bound safety directive targeting a specific mechanical defect in a specific aircraft model. It has not expanded beyond its original purpose of mandating a hydraulic pressure indicator fix."},"complexity_factors":["Very short document (under 200 words)","Only one substantive requirement with a single cross-reference to a manufacturer service bulletin","No defined terms section","Simple conditional logic ('Unless previously carried out')","Minimal cross-referencing (only two reference notes to related foreign directives)","Clear, single compliance deadline"],"plain_english_summary":"**What this is:** This is an Airworthiness Directive (AD) — essentially a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA) for specific aircraft.\n\n**What it does:** It requires owners or operators of certain SAAB SF340A aeroplanes (serial numbers 003 through 138) to carry out a specific safety fix outlined in a manufacturer service bulletin (SAAB-Scania Service Bulletin SF340-29-004 Revision 1). This fix addresses a problem with the \"Dual Pressure Indicator\" — a component that monitors hydraulic pressure.\n\n**Why it matters:** There had been reports of aircraft losing hydraulic pressure without pilots realising it. This is dangerous because it meant some planes were taxiing with broken nose wheel steering and non-working brakes — a serious safety risk on the ground. The directive forces operators to fix this before 30 June 1993 to prevent accidents.\n\n**Who it affects:** Operators of SAAB SF340A aircraft with serial numbers 003–138."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The directive, as published, applies specifically to SAAB SF340A serial numbers 003–138 and requires compliance with the referenced service bulletin by a stated date. The text does not indicate any expansion or narrowing of that applicability or any alteration of the directive's original scope."},"complexity_factors":["Applicability limited to a specific set of serial numbers (003–138) — narrow scope reduces complexity.","Mandates action by reference to an external manufacturer service bulletin (SF340-29-004 Rev 1) rather than specifying technical steps — requires access to and reliance on external document.","Fixed compliance deadline creates scheduling and operational planning requirements for operators.","Cross-references to foreign airworthiness directives (Swedish AD and FAA AD) add coordination context though implementation depends on the service bulletin.","Implementation depends on availability of parts, maintenance resources, and correct interpretation of the service bulletin (practical complexity rather than legal complexity)."],"plain_english_summary":"What this directive changes (mechanically)\n\n- The directive requires owners/operators of SAAB SF340A aeroplanes with serial numbers 003 through 138 inclusive to carry out the corrective action described in SAAB-Scania Service Bulletin SF340-29-004 Revision 1, unless that action has already been done (Requirement; Applicability).\n- The work must be completed by 30 June 1993 (Compliance).\n- The directive cross-references a Swedish airworthiness directive and a U.S. FAA directive (Note 1; Note 2).\n\nWhy the requirement was issued (official rationale)\n\n- The background given is that reports were received of aircraft experiencing loss of hydraulic pressure that was not detected by pilots, and that in several cases aircraft taxied with nose wheel steering and brakes inoperative (Background). The action mandated is presented as a response to that problem.\n\nWho is affected and who pays\n\n- Affected parties are the owners/operators of SAAB SF340A aeroplanes serial numbers 003–138 (Applicability). These operators bear the direct costs of complying: labour, parts, and aircraft downtime required to complete the service bulletin work (Requirement; Compliance).\n- Maintenance organisations contracted to perform the work are affected operationally; they must follow the service bulletin instructions when undertaking the corrective action (Requirement).\n\nPractical effects on operations and private choices\n\n- Operators must schedule the work before the compliance date or document that the work has already been done; failure to comply would leave aircraft non-conforming to the directive (Requirement; Compliance).\n- The requirement can reduce availability of affected aircraft while the work is performed, creating scheduling and potential revenue impacts for operators during the maintenance interval (Requirement; Compliance).\n- The directive references an external service bulletin rather than specifying technical details in the directive itself; this means implementation depends on the content and availability of that manufacturer bulletin (Requirement).\n\nIncentives, trade-offs and implementation risks\n\n- Incentive: operators are pushed to fix or verify the condition that allowed undetected hydraulic loss, thereby reducing the regulatory and safety risk associated with undetected hydraulic failure (Background).\n- Trade-offs: the cost and downtime of compliance versus the risk mitigation the action aims to achieve (Requirement; Compliance).\n- Implementation risks include possible delays if parts or technical support from the manufacturer are required, uncertain scope of work if the service bulletin is difficult to obtain or interpret, and the need for competent maintenance resources to carry out the bulletin instructions correctly (Requirement).\n\nCompliance burden and discretion\n\n- The directive sets a mandatory action and a deadline; it does not include alternative means of compliance in the text provided. Discretion over technical details rests primarily with the instructions in the referenced service bulletin (Requirement).\n- The AD itself enforces a compliance obligation; decisions about how to meet that obligation (scheduling, selecting a maintenance provider, managing aircraft out-of-service time) rest with operators (Requirement; Compliance).\n\nRelation to other authorities\n\n- The AD points operators to related actions or findings in a Swedish AD and an FAA AD (Note 1; Note 2), indicating coordination or alignment with foreign regulators but leaving the implementing detail to the cited service bulletin.\n\nPotential concentrated benefits and diffuse costs\n\n- The immediate safety benefit (detection of hydraulic pressure loss and prevention of taxiing with steering/brakes inoperative) is concentrated in terms of reduced operational safety incidents for each corrected aircraft (Background).\n- The costs (maintenance labour, parts, downtime) are borne by individual operators of the specified serial-numbered aircraft (Requirement; Compliance).\n\nSummary statement of purpose and mechanics\n\n- Purpose claimed in the text: to address reports of undetected hydraulic pressure loss leading to unsafe taxi operations (Background).\n- Mechanical effect: a mandatory requirement for affected aircraft to have the corrective action of SAAB-Scania Service Bulletin SF340-29-004 Revision 1 carried out by 30 June 1993, unless already completed (Requirement; Compliance; Applicability)."}},"importantCases":[],"_links":{"self":"/api/acts/ad-sf340-34-dual-pressure-indicator","history":"/api/acts/ad-sf340-34-dual-pressure-indicator/history","analysis":"/api/acts/ad-sf340-34-dual-pressure-indicator/analysis","conflicts":"/api/acts/ad-sf340-34-dual-pressure-indicator/conflicts","importantCases":"/api/acts/ad-sf340-34-dual-pressure-indicator/important-cases","documents":"/api/acts/ad-sf340-34-dual-pressure-indicator/documents"}}