{"id":"F2006B04179","name":"AD/BEECH 76/4 - Fuel Tank Outlet Check Valve and Fuel Selector Valves","slug":"ad-beech-76-4-fuel-tank-outlet-check-valve-and-fuel-selector-valves","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":43932,"registerId":"commonwealth-F2006B04179-current","compilationNumber":null,"startDate":"2026-04-02","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/BEECH 76/4 - Fuel Tank Outlet Check Valve and Fuel Selector Valves","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)  Beechcraft 76 (Duchess) Series Aeroplanes\n\n \n\n# AD/BEECH 76/4 Fuel Tank Outlet Check Valve and\n\nFuel Selector Valves\n\nApplicability: All model 76 with S/Nos. ME-1 to ME-133. Requirement:  Action in accordance with Beechcraft SI No. 1054. Compliance:               Before 1 October 1979.\n\n# 7/79\n\nBackground: The original fuel selector valves have proved unsatisfactory and are replaced with valves of an improved design, also, check valves are to be fitted at the fuel tank outlets to prevent inadvertent transfer of fuel between tanks.\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":1474},"content_quality":"ok","complexity_score":1,"scope_assessment":{"changed":false,"description":"The directive maintains its original narrow, technical scope focused solely on fuel valve modifications for specific Beechcraft 76 aircraft. There is no expansion beyond the original safety intent."},"complexity_factors":["Single, unambiguous operational requirement with no exceptions","No defined terms or interpretation section","Simple applicability criteria limited to specific aircraft serial numbers","Only one external reference (manufacturer's Service Instruction No. 1054)","Single compliance deadline with no conditional provisions or extensions"],"plain_english_summary":"**What this does:**\nThis is a mandatory safety order for specific Beechcraft Duchess aircraft (model 76, serial numbers ME-1 through ME-133). It requires aircraft owners to fix a dangerous fuel system flaw.\n\n**What must be done:**\n- Replace the original fuel selector valves with an improved design\n- Install check valves at fuel tank outlets to prevent fuel from accidentally flowing between tanks (which could cause imbalance or fuel starvation)\n\n**How to comply:**\nFollow the manufacturer's Service Instruction No. 1054. The work had to be completed before 1 October 1979.\n\n**Why it matters:**\nThe original valves were \"unsatisfactory\" (prone to failure), creating a safety risk. This directive prevents potential engine failure or loss of control due to fuel system malfunction."}},"importantCases":[],"_links":{"self":"/api/acts/ad-beech-76-4-fuel-tank-outlet-check-valve-and-fuel-selector-valves","history":"/api/acts/ad-beech-76-4-fuel-tank-outlet-check-valve-and-fuel-selector-valves/history","analysis":"/api/acts/ad-beech-76-4-fuel-tank-outlet-check-valve-and-fuel-selector-valves/analysis","conflicts":"/api/acts/ad-beech-76-4-fuel-tank-outlet-check-valve-and-fuel-selector-valves/conflicts","importantCases":"/api/acts/ad-beech-76-4-fuel-tank-outlet-check-valve-and-fuel-selector-valves/important-cases","documents":"/api/acts/ad-beech-76-4-fuel-tank-outlet-check-valve-and-fuel-selector-valves/documents"}}