{"id":"F2006B08301","name":"AD/CESSNA 400/14 - Wing Locker Fuel Tank Vent - Modification","slug":"ad-cessna-400-14-wing-locker-fuel-tank-vent-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":115690,"registerId":"commonwealth-F2006B08301-current","compilationNumber":null,"startDate":"2026-04-03","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/CESSNA 400/14 - Wing Locker Fuel Tank Vent - Modification","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)  Cessna 400 Series Aeroplanes\n\n \n\nAD/CESSNA 400/14 Wing Locker Fuel Tank Vent - Modification 2/70 Applicability:              All 421 series with S/Nos. below 421-0151 and fitted with wing locker fuel tanks. Document:               Cessna SL ME69-34.\n\nCompliance: Within 100 hours time in service after 23 March 1970.\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\n \n\n \n\n \n\n \n","sortOrder":0}],"analysis":{"kimi_summary":{"_metrics":{"model":"kimi-k2.5","source":"moonshot-batch","completionTokens":1450},"content_quality":"ok","complexity_score":1,"scope_assessment":{"changed":false,"description":"The directive maintains its original narrow scope: a specific safety modification for fuel tank vents on a limited subset of Cessna 421 aircraft. There is no indication of expansion beyond the original technical safety issue."},"complexity_factors":["Single, unambiguous applicability clause covering one aircraft model range","No defined terms or interpretation section","One straightforward compliance action with clear deadline","No cross-references to other legislative provisions or conditional exceptions"],"plain_english_summary":"**What this is:** A mandatory safety instruction (called an Airworthiness Directive) issued by the Civil Aviation Safety Authority under the Civil Aviation Regulations.\n\n**Who it affects:** Owners and operators of specific Cessna 421 series aircraft — specifically those with serial numbers below 421-0151 that have wing locker fuel tanks installed.\n\n**What it requires:** You must modify the vent system for the wing locker fuel tanks according to the technical instructions in **Cessna Service Letter ME69-34**.\n\n**When:** The modification had to be completed within 100 hours of flight time after 23 March 1970.\n\n**Why it matters:** This fixes a safety defect in the fuel tank venting system to prevent potential hazards such as fuel leaks, fire risks, or engine fuel starvation caused by improper venting."}},"importantCases":[],"_links":{"self":"/api/acts/ad-cessna-400-14-wing-locker-fuel-tank-vent-modification","history":"/api/acts/ad-cessna-400-14-wing-locker-fuel-tank-vent-modification/history","analysis":"/api/acts/ad-cessna-400-14-wing-locker-fuel-tank-vent-modification/analysis","conflicts":"/api/acts/ad-cessna-400-14-wing-locker-fuel-tank-vent-modification/conflicts","importantCases":"/api/acts/ad-cessna-400-14-wing-locker-fuel-tank-vent-modification/important-cases","documents":"/api/acts/ad-cessna-400-14-wing-locker-fuel-tank-vent-modification/documents"}}