{"id":"F2006B03454","name":"AD/BAe 146/100 - Fire Extinguisher Wiring","slug":"ad-bae-146-100-fire-extinguisher-wiring","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":43008,"registerId":"commonwealth-F2006B03454-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"AIRWORTHINESS DIRECTIVE","sectionType":"part","heading":"AIRWORTHINESS DIRECTIVE","content":"# AIRWORTHINESS DIRECTIVE\n\n![](image.001.png)\n\n![](image.001.png)  \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 CAR 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\nBritish Aerospace BAe 146 Series Aeroplanes","sortOrder":0},{"sectionNumber":"AD/BAe 146/100 Fire Extinguisher Wiring ","sectionType":"part","heading":"AD/BAe 146/100 Fire Extinguisher Wiring 12/2002","content":"# AD/BAe 146/100 Fire Extinguisher Wiring 12/2002\n\nApplicability: BAe 146 and Avro 146 RJ series aeroplanes with modifications HCM01582A (Production Installation of Pacific Scientific Fire Extinguishers) or HCM01582B (SB.26-042-01582B Retro Installation of Pacific Scientific Fire Extinguishers) and HCM01688A (Installation of Earth Stud Adaptor) previously embodied.\n\nAircraft with modification HCM01582B, are exempt from the requirements of this Directive if BAe Systems (Operations) Ltd Inspection Service Bulletin (ISB) 26-060 has been incorporated on each engine subsequent to embodiment of modification HCM01582B.\n\nRequirement: Inspect and test the left hand fire bottle wiring on all four engines in accordance with BAe Systems (Operations) Ltd ISB.26-065.\n\nNote: This Inspection Service Bulletin has been classified as Mandatory by the CAA(UK).\n\nCompliance: Before 31 March 2003.\n\nThis Airworthiness Directive becomes effective on 28 November 2002.\n\nBackground: BAe has advised that it is possible to incorrectly connect wiring circuits on Pacific Scientific engine fire extinguishers. This Directive requires an inspection and test to verify that the engine fire extinguishers are connected correctly.\n\n![Signature of Barry James Reid McKay, Delegate of the Civil Aviation Safety Authority.](image.002.png)  \n\nBarry James Reid McKay\n\nDelegate of the Civil Aviation Safety Authority 17 October 2002\n\n![](image.001.png)  \n\nThe above AD is notified in the Commonwealth of Australia Gazette on 6 November 2002.","sortOrder":1}],"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 unsafe wiring condition on a specific aircraft type with specific modifications. There is no evidence of scope creep; the directive remains tightly focused on the fire extinguisher wiring inspection requirement as originally conceived."},"complexity_factors":["Single, specific technical requirement (inspect and test wiring)","Only 3 defined modification numbers to check for applicability","One clear exemption condition (prior completion of ISB 26-060)","Single compliance deadline (31 March 2003)","No nested exceptions or conditional logic beyond the basic exemption","Short document (approximately 250 words of substantive text)","No cross-references to other legislation beyond the enabling regulation (CAR 1998 subreg 39.1(1))"],"plain_english_summary":"This safety order mandates inspection and testing of the wiring to the left-hand engine fire extinguisher bottles on BAe 146 / Avro 146 RJ aircraft per manufacturer ISB.26-065, to be completed by 31 March 2003.\n\nIt applies to aircraft fitted with fire extinguisher modifications HCM01582A or HCM01582B together with earth stud adaptor HCM01688A (HCM01582B aircraft are exempt if ISB 26-060 was done after the mod). The check addresses a fault that could leave extinguishers inoperative and risk uncontrolled engine fires."},"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"},"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The AD is narrowly focused on correcting an identified unsafe condition (possible incorrect wiring of Pacific Scientific engine fire extinguishers) for a defined subset of BAe 146/Avro 146 RJ aeroplanes. It does not broaden regulatory reach beyond that technical safety fix; the exemption pathway (ISB 26-060) refines who must comply rather than expanding scope. There is no indication in this text that the AD grew significantly beyond its original remedial purpose."},"complexity_factors":["Short, single-action directive (one inspection/test requirement).","Two modification identifiers referenced (HCM01582A and HCM01582B) plus HCM01688A.","Single exemption clause tied to incorporation of a second ISB (ISB 26-060).","Cross-reference to one mandatory Inspection Service Bulletin for the required action (ISB.26-065).","Fixed compliance deadline (31 March 2003) and effective date (28 November 2002).","No multi-layered definitions or nested exceptions; no continuing reporting or staged compliance actions."],"plain_english_summary":"**What this instrument does (mechanically)**\n\n- Requires inspection and testing of the *left-hand fire bottle wiring* on all four engines of affected BAe 146 / Avro 146 RJ aeroplanes.\n- The inspection and test must be carried out in accordance with BAe Systems (Operations) Ltd Inspection Service Bulletin ISB.26-065 (the manufacturer’s technical instruction).\n- The AD applies only to aeroplanes that have previously embodied particular BAe modifications: HCM01582A or HCM01582B (these relate to installation of Pacific Scientific fire extinguishers) and HCM01688A (earth stud adaptor).\n- Aircraft that have HCM01582B are exempt from this AD only if BAe Systems ISB 26-060 has been incorporated on each engine after HCM01582B was embodied.\n- Compliance deadline: inspections/tests must be completed by 31 March 2003. The AD became effective 28 November 2002.\n\n**Why it matters (stated purpose and operational effect)**\n\n- The stated reason (from BAe) is that wiring for Pacific Scientific engine fire extinguishers can be incorrectly connected. The AD’s mechanical purpose is to detect and correct any incorrect wiring connection so the engine fire extinguisher system will operate as intended.\n\n**Who is affected and who pays**\n\n- Affected parties: operators/owners of BAe 146 and Avro 146 RJ aeroplanes that have the listed modifications installed; maintenance organisations that carry out the inspection and any corrective work; and potentially lessors where lessee/operators must comply.\n- Who pays: the aircraft operator (or their maintenance provider/lessor as contractually arranged) bears the direct costs — labor for inspection/testing, any corrective wiring work, parts if required, and aircraft downtime while the work is done.\n\n**How it changes behaviour and decisions**\n\n- Operators must schedule the ISB.26-065 inspection/test before the compliance deadline and may need to remove aircraft from service for the work.\n- Operators of aircraft with HCM01582B can choose a different compliance path: incorporate ISB 26-060 on each engine (if not already done) to obtain the stated exemption. That choice trades the immediate inspection for the work and cost of implementing ISB 26-060.\n- Maintenance providers must follow the manufacturer’s ISB instructions precisely when performing the work if they are to meet the AD.\n\n**Costs, incentives and trade-offs**\n\n- Direct costs: technician time, any replacement/repair work, potential parts, and aircraft downtime. These are concentrated on operators of the affected fleet.\n- Incentive to incorporate ISB 26-060: for aircraft with HCM01582B, incorporating ISB 26-060 after the modification avoids the AD requirement; operators will weigh the cost/time of that work against doing the ISB.26-065 inspection.\n- Opportunity costs: time spent by aircraft in maintenance is time not earning revenue on commercial services.\n- Compliance burden: follows a manufacturer ISB (technical steps may be specialised); independent repair stations and third-party MROs can perform the work if they have the capability and follow the ISB.\n\n**Implementation risks and administrative discretion**\n\n- The AD relies on BAe’s ISB for technical steps. Misinterpretation or inconsistent application of the ISB could leave wiring faults undetected.\n- The CASA delegate issued the AD under subregulation 39.1(1) of the CAR 1998 (administrative exercise of airworthiness authority). The AD prescribes the required action and deadline; enforcement and approval of corrective actions rest with the relevant civil aviation authority and approved maintenance organisations.\n\n**Effects on market participants and competition**\n\n- The AD creates demand for inspection and possible corrective services; maintenance providers with BAe technical material and experience are likely to capture that work. However, the AD does not expressly limit who may perform the work so long as the ISB is followed and approvals are obtained — independent MROs can compete if they meet regulatory requirements.\n\n**Summary assessment of the substantive change vs. stated purpose**\n\n- The AD implements a narrowly targeted safety check aimed at verifying and correcting potentially incorrect wiring of engine fire extinguishers. It operates by mandating a manufacturer-prescribed inspection/test or by accepting a specified manufacturer update (ISB 26-060) as an exemption for one modification. The action, deadline, affected population, and exemption path are specific and mechanically limited to correcting the identified wiring risk.\n\n(References: Applicability, Requirement, Compliance, Background sections of the AD.)"}},"importantCases":[],"_links":{"self":"/api/acts/ad-bae-146-100-fire-extinguisher-wiring","history":"/api/acts/ad-bae-146-100-fire-extinguisher-wiring/history","analysis":"/api/acts/ad-bae-146-100-fire-extinguisher-wiring/analysis","conflicts":"/api/acts/ad-bae-146-100-fire-extinguisher-wiring/conflicts","importantCases":"/api/acts/ad-bae-146-100-fire-extinguisher-wiring/important-cases","documents":"/api/acts/ad-bae-146-100-fire-extinguisher-wiring/documents"}}