{"id":"F2006B02824","name":"AD/B737/122 - Fuel Valve Actuator Replacement","slug":"ad-b737-122-fuel-valve-actuator-replacement","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":42166,"registerId":"commonwealth-F2006B02824-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/B737/122 - Fuel Valve Actuator Replacement","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/B737/122 Fuel Valve Actuator Replacement 13/98\n\nApplicability: Model 737 aircraft equipped with J. C. Carter Company Fuel Valve Actuators having part number (P/N) 40574-2 (Kearfott Models 3715-7 and -8) or 40574-5 (Kearfott\n\nModel 3715-9).\n\nRequirement: Replace all effected fuel valve actuators with acceptable items in accordance with the directions given in either J.C. Carter Company Service Bulletin 61163-28-09 dated 28 September 1995, or J. C. Carter Company Service Bulletin 61163-28-09 dated\n\n1 May 1996.\n\nNote: FAA AD 98-18-20 Amendment 39-10736 refers.\n\nCompliance: Within 36 months of the effective date of this Directive.\n\nThis Airworthiness Directive becomes effective on 3 December 1998.\n\nBackground: Service experience has revealed a possible fault in the subject actuators which could prevent the pilot from shutting off the fuel to the engine following an engine failure and/or fire. This Directive has been raised to replace the effected components with serviceable items.","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This Airworthiness Directive maintains its original narrow scope. It addresses a specific safety defect in specific aircraft components and mandates a specific replacement action. There is no evidence of scope creep; the directive remains tightly focused on the fuel valve actuator replacement issue as originally intended."},"complexity_factors":["Single, specific technical requirement (replace identified part)","Limited applicability (only two specific part numbers on Boeing 737 series)","Clear compliance deadline (36 months from effective date)","Only two cross-references (to manufacturer Service Bulletins and FAA AD)","No nested conditions, exceptions, or defined terms section","Background section provides straightforward safety rationale","Document is extremely short (under 200 words)"],"plain_english_summary":"This CASA safety order requires operators of certain Boeing 737s fitted with J.C. Carter fuel valve actuators (parts 40574-2 or 40574-5) to replace those actuators because they can prevent shutting off engine fuel in an emergency.  \n\nThe replacement, done per the manufacturer service bulletins, was mandatory within 36 months of 3 Dec 1998 (deadline Dec 2001); noncompliance would breach aviation regulations."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"Scope remains focused on replacing the identified faulty actuators on Boeing 737s equipped with those exact part numbers. The directive’s applicability (specific P/Ns and models), required remedy (service-bulletin-directed replacement), and compliance timeframe align with the stated safety purpose of preventing inability to shut off engine fuel after failure or fire (Applicability; Requirement; Compliance; Background)."},"complexity_factors":["Narrow technical scope — applies only to Boeing 737 aircraft fitted with specific J.C. Carter actuator part numbers (Applicability).","Clear mandatory action — replacement required (Requirement) with specified service bulletins as the compliance method.","Fixed deadline — single compliance window of 36 months from the effective date (Compliance).","Multiple acceptable service bulletin dates referenced (28 Sep 1995 or 1 May 1996), requiring operators to follow one of two versions (Requirement).","Operational cost borne by aircraft operators/owners to procure and install replacement actuators (implicit from Requirement and Applicability).","No exemption or alternative means of compliance stated in the text — limited administrative discretion (Requirement/Compliance).","Cross-reference to FAA AD 98-18-20 suggests alignment with international regulator action and may affect imported or leased aircraft (Note).","Technical safety rationale is specific and narrowly defined: risk that actuators could prevent shutting off fuel after engine failure/fire (Background)."],"plain_english_summary":"Requires operators of Boeing 737s fitted with J.C. Carter fuel‑valve actuators (P/N 40574‑2 or 40574‑5) to replace those actuators with acceptable items per the specified J.C. Carter service bulletins within 36 months. The action is prompted by reports that the subject actuators might stop pilots being able to shut off engine fuel after an engine failure or fire."}},"importantCases":[],"_links":{"self":"/api/acts/ad-b737-122-fuel-valve-actuator-replacement","history":"/api/acts/ad-b737-122-fuel-valve-actuator-replacement/history","analysis":"/api/acts/ad-b737-122-fuel-valve-actuator-replacement/analysis","conflicts":"/api/acts/ad-b737-122-fuel-valve-actuator-replacement/conflicts","importantCases":"/api/acts/ad-b737-122-fuel-valve-actuator-replacement/important-cases","documents":"/api/acts/ad-b737-122-fuel-valve-actuator-replacement/documents"}}