{"id":"F2006B05278","name":"AD/CESSNA 207/19 Amdt 1 - Vented Fuel Caps","slug":"ad-cessna-207-19-amdt-1-vented-fuel-caps","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":45656,"registerId":"commonwealth-F2006B05278-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/CESSNA 207/19 Amdt 1 - Vented Fuel Caps","content":"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n![](image.001.png)  \nCessna 207 Series Aeroplanes\n\nAD/CESSNA 207/19\n\nAmdt 1\n\n  \nVented Fuel Caps 8/80\n\nApplicability: Models 207 and T207 with S/Nos 20700001 to 20700203. Requirement: Install vented fuel cap(s) in accordance with Cessna SL No SE77-6.\n\nNote: FAA AD 79-10-14, Amendment 39-3475 refers.\n\nNote: Installation of a placard is not an acceptable alternative to installation of vented fuel caps.\n\nCompliance: Within 100 hours time in service after 31 August 1979 or before 1 January 1980, whichever is the later.\n\nBackground: To guard against the possibility of either an obstructed primary vent or sticking of the fuel tank vent valve it has been found necessary to provide secondary venting in the form of vented fuel caps. Due to some misinterpretation of this Directive a NOTE has now been added to disallow the fitting of a placard.","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":true,"description":"The amendment narrows acceptable compliance methods by adding an explicit note that installation of a placard is not an acceptable alternative to fitting vented fuel caps. The core requirement (install vented fuel caps per Cessna SL No SE77-6), the affected models/serial numbers, and the compliance deadline remain in the text, but the amendment removes a previously misinterpreted alternative measure, thereby tightening the scope of acceptable remedial action (Note; Background; Requirement; Applicability; Compliance)."},"complexity_factors":["Narrow applicability limited to specific models and serial numbers (Applicability).","Single prescriptive corrective action required (install vented fuel caps in accordance with Cessna SL No SE77-6) rather than multiple options (Requirement).","Explicit prohibition of an alternative mitigation (placard not acceptable) reduces interpretative complexity but changes compliance options (Note).","Short and concrete compliance timeframe creates scheduling and planning constraints for operators (Compliance).","Reference to an external manufacturer document (Cessna SL No SE77-6) requires access to and reliance on that service letter for technical steps (Requirement).","Regulatory origin and enforcement by the Civil Aviation Safety Authority are straightforward; there is little delegated discretion in the text itself (header; Requirement)."],"plain_english_summary":"This directive mandates installation of vented fuel caps per Cessna Service Letter No SE77-6 on Cessna 207/T207 aeroplanes serial numbers 20700001–20700203 to provide secondary tank venting (guarding against obstructed primary vents or stuck vent valves). It forbids using a placard as an alternative. Owners/operators must install and pay for the caps within 100 hours TIS after 31 Aug 1979 or before 1 Jan 1980, whichever is later; the Civil Aviation Safety Authority enforces compliance."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is Amendment 1 to an existing AD. The amendment adds only a clarifying note that placards are not acceptable alternatives to vented caps. The scope remains tightly focused on the original safety issue (fuel tank venting) and does not expand to other aircraft systems or models."},"complexity_factors":["Very short document (under 200 words)","Only 2 defined applicability criteria (model numbers and serial number range)","Single straightforward requirement with reference to external technical document (Cessna Service Letter SE77-6)","Simple compliance deadline with clear 'whichever is later' logic","No nested exceptions, conditional clauses, or cross-references to other legislation beyond a single FAA AD reference for context","Plain language background explanation included"],"plain_english_summary":"**What this is:** An Airworthiness Directive (AD) — essentially a mandatory safety fix ordered by Australia's aviation regulator (CASA) for specific aircraft.\n\n**What it does:** Requires owners of certain Cessna 207 aeroplanes to replace their standard fuel caps with **vented fuel caps**. These special caps have built-in openings that let air into the fuel tanks, preventing dangerous pressure build-up.\n\n**Who it affects:** Owners and operators of Cessna 207 and T207 model aircraft with serial numbers 20700001 through 20700203.\n\n**Why it matters:** The original fuel system design had a flaw. If the main vent got blocked or the vent valve stuck, fuel tanks could develop vacuum pressure or pressure build-up. This could cause engine fuel starvation (the engine cuts out from lack of fuel) or structural damage. The vented caps provide a backup (secondary) venting system to prevent accidents.\n\n**Key requirement:** You **must** install the vented caps — you cannot simply put a warning sticker (placard) on the dashboard instead. This clarification was added because some operators tried to cheat the system with just a placard.\n\n**When it had to be done:** Within 100 hours of flying time after 31 August 1979, or before 1 January 1980 — whichever gave more time."}},"importantCases":[],"_links":{"self":"/api/acts/ad-cessna-207-19-amdt-1-vented-fuel-caps","history":"/api/acts/ad-cessna-207-19-amdt-1-vented-fuel-caps/history","analysis":"/api/acts/ad-cessna-207-19-amdt-1-vented-fuel-caps/analysis","conflicts":"/api/acts/ad-cessna-207-19-amdt-1-vented-fuel-caps/conflicts","importantCases":"/api/acts/ad-cessna-207-19-amdt-1-vented-fuel-caps/important-cases","documents":"/api/acts/ad-cessna-207-19-amdt-1-vented-fuel-caps/documents"}}