{"id":"F2006B02926","name":"AD/B737/230 - Engine Fire extinguisher Squib Firing Circuit","slug":"ad-b737-230-engine-fire-extinguisher-squib-firing-circuit","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":42268,"registerId":"commonwealth-F2006B02926-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"AIRWORTHINESS DIRECTIVE","sectionType":"part","heading":"AIRWORTHINESS DIRECTIVE","content":"# ![](image.001.png)  \nAIRWORTHINESS DIRECTIVE\n\nFor the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (AD) under subregulation 39.1 (1) of CASR 1998. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.\n\n![](image.001.png)  \n\nBoeing 737 Series Aeroplanes","sortOrder":0},{"sectionNumber":"AD/B737/230 Engine Fire extinguisher Squ","sectionType":"part","heading":"AD/B737/230 Engine Fire extinguisher Squib Firing Circuit 11/2004","content":"# AD/B737/230 Engine Fire extinguisher Squib Firing Circuit 11/2004\n\nApplicability: Model 737-600, 737-700, 737-700C, 737-800 and 737-900 series aeroplanes, as listed in Boeing Alert Service Bulletin (ASB) 737-26A1118, Revision 1, dated 8 April 2004.\n\nRequirement: 1. Measure the electrical resistance of the dual ground studs of the support brackets for the fire extinguisher bottle located in the left main landing gear wheel well by accomplishing all actions specified in the Accomplishment Instructions of ASB 737-26A1118, Revision 1.\n\n2. Correct any anomalies detected during the Requirement 1 resistance measurements.\n\nActions accomplished before the effective date of this Directive in accordance with either Boeing Telex M-7200-02-01401, dated 9 September 2002 or ASB 737- 26A1118, dated 17 October 2002 are considered acceptable for compliance with the corresponding action specified in this Directive.\n\nNote: FAA AD 2004-18-02 Amdt 39-13779 refers.\n\nCompliance: For Requirement 1 \\- Within 90 days after the effective date of this Directive.\n\nFor Requirement 2 \\- Before further flight after the Requirement 1 resistance measurements.\n\nThis Airworthiness Directive becomes effective on 28 October 2004.","sortOrder":1}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The directive applies to the Boeing 737 variants listed and mandates measurement plus correction per the referenced Boeing ASB; it does not expand or narrow scope beyond those models. It also accepts completion under specified earlier Boeing telex/ASB, so the AD preserves prior-compliance pathways rather than changing applicability or substantive requirements (Applicability; Requirement; Compliance)."},"complexity_factors":["Reference to external manufacturer document (ASB 737-26A1118, Revision 1) for procedural detail creates dependency on obtaining and following that Service Bulletin (Requirement: \"accomplishing all actions specified in the Accomplishment Instructions of ASB 737-26A1118, Revision 1\").","Limited technical scope — a single measurable parameter (electrical resistance of dual ground studs) reduces procedural complexity (Requirement: 1).","Corrective action scope delegated to maintenance procedures in the ASB rather than fully specified in the AD, producing discretion for maintenance providers within ASB instructions (Requirement: 2).","Time-bound compliance creates operational scheduling pressure: measurement within 90 days and repairs before further flight (Compliance: \"Within 90 days\"; \"Before further flight\").","Applicability restricted to specific 737 variants defined by the ASB, so fleet applicability must be determined by operators (Applicability: listed models and ASB reference).","Acceptance of prior actions under earlier Boeing notices reduces redundancy but requires record-checking to confirm eligibility (Requirement: acceptance clause referencing Boeing Telex and earlier ASB)."],"plain_english_summary":"This Airworthiness Directive forces operators of specified Boeing 737-600/700/700C/800/900 aeroplanes to measure the electrical resistance of the dual ground studs for the left main landing-gear fire‑extinguisher bottle and to repair any anomalies, following Boeing Alert Service Bulletin 737-26A1118 Rev 1. Measurements must be done within 90 days and any required repairs completed before the next flight; certain earlier Boeing telex/ASB work is accepted as compliant."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a standard airworthiness directive with narrow, targeted scope addressing a specific unsafe condition in a defined aircraft system. The scope remains precisely limited to the electrical grounding issue in the fire extinguisher circuit."},"complexity_factors":["Single, specific technical requirement with clear mechanical action (resistance measurement)","Only 2 defined compliance paths (the 90-day inspection and immediate repair if needed)","No nested exceptions or conditional logic beyond the grandfathering clause for prior work","Cross-reference to only one external document (Boeing ASB 737-26A1118)","Short length (approximately 200 words of operative text)","Single applicability criterion (specific aircraft models)"],"plain_english_summary":"This safety order requires operators of certain Boeing 737s (-600/-700/-700C/-800/-900 per Boeing ASB 737-26A1118) to measure the electrical resistance of the squib firing circuit ground connections for the engine fire extinguishers in the left main landing gear wheel well within 90 days, and to correct any faulty resistance before the aircraft returns to service. It ensures the extinguishers will function in an engine fire, protecting crew, passengers, and the airplane."},"flash_summary_failed":{"failed":true,"reason":"A positive credit balance is required for all requests, including BYOK, so fallback providers remain available. Add credits at https://vercel.com/d?to=%2F%5Bteam%5D%2F%7E%2Fai%3Fmodal%3Dtop-up to continue.","source":"analysis-cron"}},"importantCases":[],"_links":{"self":"/api/acts/ad-b737-230-engine-fire-extinguisher-squib-firing-circuit","history":"/api/acts/ad-b737-230-engine-fire-extinguisher-squib-firing-circuit/history","analysis":"/api/acts/ad-b737-230-engine-fire-extinguisher-squib-firing-circuit/analysis","conflicts":"/api/acts/ad-b737-230-engine-fire-extinguisher-squib-firing-circuit/conflicts","importantCases":"/api/acts/ad-b737-230-engine-fire-extinguisher-squib-firing-circuit/important-cases","documents":"/api/acts/ad-b737-230-engine-fire-extinguisher-squib-firing-circuit/documents"}}