{"id":"F2006B04886","name":"AD/CASA/6 - Fuel Shut-Off Valves - Replacement","slug":"ad-casa-6-fuel-shut-off-valves-replacement","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":44693,"registerId":"commonwealth-F2006B04886-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/CASA/6 - Fuel Shut-Off Valves - Replacement","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)  Casa 212 Series Aeroplanes\n\n \n\nAD/CASA/6 Fuel Shut-Off Valves - Replacement 9/83\n\nApplicability: All Casa 212 models as referenced in requirement document. Document: Casa SB No. 212-28-15.\n\nCompliance: Before further flight after 31st August 1983.\n\n \n\nBackground: The manufacturer advises that failures have been discovered in the operation of fuel shut-off valves.\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\n \n\n \n\n \n","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The provided text does not indicate any change from an earlier scope or intent. The directive applies to all referenced Casa 212 models and mandates replacement of fuel shut-off valves per the manufacturer service bulletin, with a single compliance deadline. There is no wording in the source that alters or expands this scope beyond the stated applicability and requirement."},"complexity_factors":["Narrow technical scope limited to fuel shut-off valves on Casa 212 models (\"Applicability\").","Clear, single compliance deadline: must be done before further flight after 31 August 1983 (\"Compliance\").","Action specified by reference to a single manufacturer service bulletin rather than multiple procedures (\"Document: Casa SB No. 212-28-15\").","No staged inspections, conditional criteria, or continuing monitoring requirements described in the text.","No quantification of costs, parts availability, or alternative compliance paths in the provided text, reducing procedural complexity but leaving operational logistics to implementers."],"plain_english_summary":"### What this instrument does\n\nThis is an Airworthiness Directive titled AD/CASA/6 — \"Fuel Shut-Off Valves - Replacement\" applying to Casa 212 series aeroplanes. It requires replacement of the fuel shut-off valves in the aircraft models listed in the referenced manufacturer document (Casa SB No. 212-28-15). The directive must be complied with before any further flight after 31 August 1983. (See: \"Applicability\", \"Document\", \"Compliance\".)\n\n### Who it affects\n\n- Aircraft owners and operators of the Casa 212 models referenced in the requirement document (\"Applicability\").\n- Maintenance organisations and technicians who perform the replacement work per the manufacturer service bulletin (\"Document: Casa SB No. 212-28-15\").\n- The Civil Aviation Safety Authority as the issuing regulator (header: Civil Aviation Safety Authority, Airworthiness Directives schedule).\n\n### Why it matters (stated purpose and practical effects)\n\n- Stated purpose: the manufacturer reported discovered failures in the operation of fuel shut-off valves (\"Background\"). The directive implements the manufacturer recommendation by mandating replacement.\n- Practical effect: affected aeroplanes must have the specified fuel shut-off valves replaced before they fly again after the stated cut-off date (\"Compliance\"), which enforces a change in maintenance actions and creates immediate downtime until the work is done.\n\n### Who pays, who decides, and what changes in behaviour\n\n- Who decides: the Civil Aviation Safety Authority issues the directive; the requirement points to a specific manufacturer service bulletin for the technical procedure (header and \"Document\").\n- Who pays: the directive makes the replacement mandatory but does not state funding. Practically, aircraft owners/operators and/or their maintenance providers will pay for the parts and labour required by the service bulletin (inferred from the compliance requirement and referenced service bulletin: \"Compliance\", \"Document\").\n- Behaviour change: operators must ground affected aircraft until the replacement is completed (since compliance is required before further flight); maintenance organisations must perform the replacement per the service bulletin.\n\n### Trade-offs, costs and implementation issues (source-grounded)\n\n- The source states only that valve failures were discovered and mandates replacement; it does not quantify costs, labour time, parts availability, or specify inspection intervals (\"Background\", \"Document\", \"Compliance\").\n- Immediate costs and opportunity costs: operators face expenditure for parts and labour and loss of aircraft availability until replacement is carried out (implied by the \"before further flight\" compliance requirement).\n- Compliance burden: the AD imposes a mandatory corrective maintenance action tied to a specific manufacturer document; operators must follow that document to comply (\"Document: Casa SB No. 212-28-15\").\n- Bureaucratic discretion: the AD itself prescribes the action and deadline; the text provided contains no discretionary exemptions or alternative compliance methods.\n\n### Implementation risk and substitution effects\n\n- Implementation risk includes potential grounding and scheduling difficulties if parts or maintenance capacity are limited; the AD text does not address logistics or provide alternatives (\"Compliance\", \"Document\").\n- Substitution effects (not specified in the source): operators may prioritise replacement scheduling, relocate aircraft, or lease replacements to manage operational impact, but those responses are not described in the directive.\n\n(Referenced sections from the provided text: \"Applicability\", \"Document: Casa SB No. 212-28-15\", \"Compliance: Before further flight after 31st August 1983\", \"Background: The manufacturer advises that failures have been discovered in the operation of fuel shut-off valves.\")"},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, time-bound safety directive with a single purpose: mandating replacement of a specific faulty component. It has not expanded beyond its original scope of addressing the fuel valve failure issue identified by the manufacturer."},"complexity_factors":["Extremely short document (under 200 words)","Only one substantive requirement: replace valves before a fixed deadline","No defined terms section — uses plain language ('Before further flight')","Single cross-reference to manufacturer service bulletin (Casa SB No. 212-28-15)","No conditional logic, exceptions, or nested provisions","Binary applicability: applies to all CASA 212 models or none"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** — essentially a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA). It applies to all **CASA 212 series aircraft** (a type of twin-turboprop aeroplane).\n\n**What it requires:**\n- Aircraft operators must **replace faulty fuel shut-off valves** on these planes.\n- The work must be done **before any further flight after 31 August 1983**.\n\n**Why it matters:**\n- The manufacturer discovered that these valves were **failing in operation**.\n- Fuel shut-off valves are critical safety components — they allow pilots to cut off fuel supply to engines in an emergency (such as fire or engine failure). If they fail, pilots cannot isolate fuel systems, creating serious fire and crash risks.\n\n**Who must comply:**\n- Anyone operating a CASA 212 aircraft in Australia must follow this directive. Non-compliance means the aircraft cannot legally fly.\n\nThis is a **time-critical safety mandate** — not optional maintenance, but a legal requirement to keep airworthiness certification valid."}},"importantCases":[],"_links":{"self":"/api/acts/ad-casa-6-fuel-shut-off-valves-replacement","history":"/api/acts/ad-casa-6-fuel-shut-off-valves-replacement/history","analysis":"/api/acts/ad-casa-6-fuel-shut-off-valves-replacement/analysis","conflicts":"/api/acts/ad-casa-6-fuel-shut-off-valves-replacement/conflicts","importantCases":"/api/acts/ad-casa-6-fuel-shut-off-valves-replacement/important-cases","documents":"/api/acts/ad-casa-6-fuel-shut-off-valves-replacement/documents"}}