{"id":"F2006B02986","name":"AD/B737/85 - Fuel Actuator Shutoff Valve","slug":"ad-b737-85-fuel-actuator-shutoff-valve","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":42345,"registerId":"commonwealth-F2006B02986-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/B737/85 - Fuel Actuator Shutoff Valve","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)  \nBoeing 737 Series Aeroplanes\n\nAD/B737/85 Fuel Actuator Shutoff Valve 6/95\n\nApplicability: All model 737 series aircraft fitted with J.C. Carter actuator P/N 40574-2 used in any of the following J.C. Carter fuel system valves.\n\n| J.C Carter P/N | Boeing P/N  |\n| -------------- | ----------- |\n| 6563           | 10-60529-1  |\n| 60128          | 10-60529-5  |\n| 61163          | 10-60529-8  |\n| 61183          | 10-60529-10 |\n| 61185          | 10-60529-11 |\n\nNote: The above valve assemblies are used on the 737 fuel shutoff and crossfeed positions.\n\nRequirement: Action in accordance with J.C. Carter SB 61163-28-08. Compliance: By 31 May 1997.\n\nBackground: The valve manufacturer has advised that while functional testing a Boeing 737 gate valve, when the valve was selected to either the “open” or “close” position the actuator suffered a clutch slippage problem whenever the temperature dropped below minus twenty degrees C (minus five degrees F).","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, targeted safety directive addressing a specific mechanical defect. It has not expanded beyond its original purpose of mandating a fix for cold-weather clutch slippage in specific fuel valve actuators."},"complexity_factors":["Single, specific technical requirement referencing an external manufacturer document","Narrow applicability limited to specific part numbers and aircraft model","No conditional logic, exceptions, or nested provisions","Only one defined term implicitly used (the part number references)","Total length: approximately 150 words of substantive content"],"plain_english_summary":"This is an **Airworthiness Directive** — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA). It requires owners and operators of Boeing 737 aircraft to inspect or fix a specific mechanical problem.\n\n**What it does:**\n- Targets a faulty fuel valve actuator (a small motor that opens and closes fuel valves) made by J.C. Carter\n- The actuator can slip and fail when temperatures drop below -20°C, potentially preventing pilots from shutting off or transferring fuel in cold weather\n- Requires operators to follow the manufacturer's service bulletin (SB 61163-28-08) to fix the problem\n\n**Who it affects:**\n- All Boeing 737 operators in Australia using the specific J.C. Carter actuator model 40574-2 in their fuel shutoff or crossfeed valves\n- Covers five specific valve part numbers listed in the table\n\n**Why it matters:**\n- A failed fuel valve in cold conditions could prevent crew from isolating fuel leaks or managing fuel balance — serious safety risks during flight\n- Compliance was mandatory by 31 May 1997 (though this directive is now historical)\n\n**Key terms explained:**\n- **Airworthiness Directive (AD):** A legally enforceable safety notice that aircraft owners must follow\n- **Service Bulletin:** Manufacturer's instructions for fixing a known defect\n- **Crossfeed valve:** Allows fuel to flow between left and right wing tanks"},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The directive applies to a narrowly defined set of aircraft/parts and mandates corrective action per a specific manufacturer Service Bulletin by a fixed date. The source text does not indicate any change from an earlier or broader scope; it targets only 737 aircraft fitted with J.C. Carter actuator P/N 40574-2 used in the listed valve assemblies and requires the SB action (Applicability; table; Requirement; Compliance)."},"complexity_factors":["Technical specificity of affected parts: requires matching actuator P/N 40574-2 to several valve assembly P/Ns (Applicability and table).","Cross-reference to an external technical document (J.C. Carter SB 61163-28-08) for the required corrective action (Requirement).","Mandatory compliance date that creates scheduling and operational constraints (Compliance).","Limited regulatory detail on the technical fix—operators must obtain and implement the manufacturer Service Bulletin (Requirement)."],"plain_english_summary":"This airworthiness directive mandates that operators of Boeing 737s fitted with J.C. Carter actuator P/N 40574‑2 in the listed fuel valve assemblies must perform the maintenance actions in J.C. Carter Service Bulletin 61163‑28‑08 to remedy clutch slippage observed below −20°C. The work must be completed by 31 May 1997; affected operators or their maintainers bear the cost and schedule the required downtime to comply."}},"importantCases":[],"_links":{"self":"/api/acts/ad-b737-85-fuel-actuator-shutoff-valve","history":"/api/acts/ad-b737-85-fuel-actuator-shutoff-valve/history","analysis":"/api/acts/ad-b737-85-fuel-actuator-shutoff-valve/analysis","conflicts":"/api/acts/ad-b737-85-fuel-actuator-shutoff-valve/conflicts","importantCases":"/api/acts/ad-b737-85-fuel-actuator-shutoff-valve/important-cases","documents":"/api/acts/ad-b737-85-fuel-actuator-shutoff-valve/documents"}}