{"id":"F2006B03542","name":"AD/BAe 146/95 Amdt 2 - Ceramic Terminal Blocks","slug":"ad-bae-146-95-amdt-2-ceramic-terminal-blocks","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":43109,"registerId":"commonwealth-F2006B03542-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/BAe 146/95 Amdt 2 - Ceramic Terminal Blocks","content":"![](image.001.png)\n\n![](image.001.png)  \nAIRWORTHINESS DIRECTIVE\n\nFor the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive (AD) AD/BAe 146/95 Amdt 1 and issues the following 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\n![](image.001.png)\n\nBritish Aerospace BAe 146 Series Aeroplanes\n\nAD/BAe 146/95\n\nAmdt 2\n\n  \nCeramic Terminal Blocks 8/2002\n\nApplicability: All BAe 146 100, 200 and 300 series aeroplanes.\n\nAll Avro 146-RJ70, RJ85 and RJ100 series aeroplanes.\n\nRequirement: Incorporate Modification HCM01693A in accordance with BAe Systems Mandatory Modification Service Bulletin SB.71-077-01693A Revision 2 dated 28 May 2002.\n\nNote: This Modification Service Bulletin has been classified as Mandatory by the CAA(UK).\n\nCompliance: Before 31 July 2004.\n\nThis Amendment becomes effective on 8 August 2002.\n\nBackground: BAe initially advised that an investigation into the use of ‘Low Temp’ terminal blocks ‘G’ in engine zones 412, 422, 432 and 442 identified the requirement to replace existing terminal blocks with a ceramic terminal block that meets the fireproof requirements of these zones.\n\nThe original issue of this Directive required replacement of the existing terminal blocks with ceramic terminal blocks.\n\nAmendment 1 was issued following advice from BAe that the original ceramic terminal block mounting screws (Part Number AV0022B24) were too short\n\nThis Amendment follows the issue of Revision 2 of the service bulletin which revises the compliance time, introduces changed part numbers and additional installation notes.\n\nThe original issue of this Airworthiness Directive became effective on 27 December 2001.\n\nBritish Aerospace BAe 146 Series Aeroplanes\n\nAD/BAe 146/95 Amdt 2 (continued)\n\nAmendment 1 of this Airworthiness Directive became effective on 11 July 2002.\n\n![Signature of Eugene Paul Holzapfel, Delegate of the Civil Aviation Safety Authority.](image.002.png)  \n\nEugene Paul Holzapfel\n\nDelegate of the Civil Aviation Safety Authority 26 June 2002\n\n![](image.001.png)  \n\nThe above AD is notified in the Commonwealth of Australia Gazette on 17 July 2002.","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"This Amendment (Amdt 2) does not expand the AD’s substantive scope beyond the original safety objective (replace non-compliant terminal blocks with ceramic terminal blocks). Instead it refines implementation details: it adopts Revision 2 of the BAe service bulletin, updates part numbers, adds installation notes, and revises compliance timing. Those are procedural and technical refinements rather than a material change of purpose or addition of new categories of affected aircraft."},"complexity_factors":["Single, discrete mandatory action (incorporate Modification HCM01693A)","One primary external reference: BAe Systems Mandatory Modification Service Bulletin SB.71-077-01693A Revision 2 (dated 28 May 2002)","Single compliance deadline (before 31 July 2004)","Applicability limited to defined aircraft types (BAe 146 100/200/300 and Avro 146-RJ70/85/100)","Short background notes describing earlier amendments and reasons (screw length issue and revised part numbers)","Low number of internal cross-references or defined terms","Reference to CAR 1998 subregulation 39.1(1) for enforcement authority"],"plain_english_summary":"**What this instrument does (mechanics)**\n\n- This is an Airworthiness Directive (AD) that requires certain BAe 146 and Avro 146-RJ aeroplanes to have their existing electrical terminal blocks in specified engine zones replaced with a ceramic terminal block modification (Modification HCM01693A).\n- The replacement must be carried out exactly in accordance with BAe Systems Mandatory Modification Service Bulletin SB.71-077-01693A Revision 2 dated 28 May 2002.\n- The AD applies to: all BAe 146 series 100, 200 and 300 aeroplanes and all Avro 146-RJ70, RJ85 and RJ100 aeroplanes (see “Applicability”).\n- Compliance must be completed before 31 July 2004 (see “Compliance”).\n- The AD revokes an earlier version (Amdt 1) and replaces it with this amended requirement that reflects Revision 2 of the BAe service bulletin (see “Requirement” and “Background”).\n\n**Who is affected**\n\n- Aircraft owners, operators and maintenance organisations that operate or maintain affected BAe 146 and Avro 146-RJ aircraft.\n- Maintenance suppliers and parts providers who must supply the correct ceramic terminal blocks and any changed part numbers or associated hardware called for by the service bulletin.\n\n**Why the change was made (stated reason)**\n\n- BAe investigated the use of certain ‘Low Temp’ terminal blocks in engine zones 412, 422, 432 and 442 and identified that those terminal blocks should be replaced by ceramic terminal blocks to meet the fireproofing requirements of those engine zones. The AD reproduces that corrective action.\n- Amendment 1 had previously adjusted hardware (mounting screw) issues; this Amendment 2 incorporates Revision 2 of the service bulletin which revises the compliance time, updates part numbers and adds installation notes.\n\n**Practical effects and who pays/decides**\n\n- Who decides: the Civil Aviation Safety Authority (CASA) delegate has issued the AD and sets the compliance obligation. The operator must follow the BAe service bulletin that the AD mandates.\n- Who pays: aircraft owners/operators bear the direct costs — purchasing parts, paying for labour, and arranging aircraft downtime while the modification is carried out. Maintenance organisations bear implementation responsibility and any supply-chain effort.\n- What behaviour changes: operators must plan and schedule the modification by the compliance deadline, use the specified parts and follow the service bulletin’s installation instructions rather than leaving the existing terminal blocks in service.\n\n**Costs, incentives and practical trade-offs (implementation-focused)**\n\n- Direct costs: purchase of ceramic terminal blocks (and any revised hardware), technician labour, and aircraft downtime for the modification.\n- Timing and scheduling cost: the AD gives a firm deadline (31 July 2004), which can concentrate workload and lead operators to reschedule maintenance or accept additional AOG (aircraft on ground) risk if parts are scarce.\n- Supply-chain risk: Revision 2 changes part numbers and installation notes; if replacement parts or revised hardware are in short supply or require different suppliers, operators may face delays or premium pricing.\n- Compliance certainty: the AD mandates work “in accordance with” the BAe mandatory service bulletin. This centralises the technical solution with the manufacturer’s instructions; operators have limited discretion to adopt alternative corrective actions unless explicitly approved by the regulator.\n\n**Implementation risks and unintended effects to monitor**\n\n- If the revised part numbers or additional installation notes are not clearly available or understood by maintenance teams, there is risk of incorrect installation or delays.\n- Concentrated scheduling pressure near the compliance date could raise labour rates or create bottlenecks at approved maintenance providers.\n- The AD creates a compliance obligation tied to a manufacturer’s service bulletin classified as Mandatory by another regulator (CAA(UK)); this increases dependence on the manufacturer’s specified parts and processes.\n\n**Source claims vs operational trade-offs**\n\n- The AD’s stated purpose is to meet fireproofing requirements in specific engine zones (Background). That purpose implies a safety benefit concentrated on reducing fire propagation risk in those zones.\n- The operational trade-off is the financial and scheduling cost to operators and the practical dependence on the service bulletin (and the parts it specifies). The AD does not quantify costs or supply availability; operators must evaluate those when implementing the mandatory modification.\n\n(See: “Applicability”, “Requirement”, “Compliance” and “Background” sections of the AD.)"},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"The legislation maintains its original narrow scope: mandating a specific safety modification to terminal blocks in engine zones of BAe 146 aircraft. While this is the second amendment, it refines the technical implementation (screw length, part numbers, compliance timing) without expanding beyond the original safety purpose."},"complexity_factors":["Single, specific technical requirement (one modification to install)","Only 4 defined aircraft series in applicability section","Clear compliance deadline (single date, no conditional triggers)","No nested exceptions or conditional logic","Short document (approximately 300 words)","Cross-reference to only one external document (the Service Bulletin)","Straightforward amendment history explaining evolution from previous versions"],"plain_english_summary":"This safety order requires Australian operators of BAe 146 and Avro RJ series aeroplanes to replace specified electrical terminal blocks in engine zones with fireproof ceramic units, following the manufacturer's Service Bulletin, and complete the work before 31 July 2004. It prevents loss of critical electrical systems during an engine fire. Amendment 2 corrects a short-screw issue in the original ceramic blocks and incorporates the manufacturer’s revised bulletin with updated part numbers and installation guidance."},"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-bae-146-95-amdt-2-ceramic-terminal-blocks","history":"/api/acts/ad-bae-146-95-amdt-2-ceramic-terminal-blocks/history","analysis":"/api/acts/ad-bae-146-95-amdt-2-ceramic-terminal-blocks/analysis","conflicts":"/api/acts/ad-bae-146-95-amdt-2-ceramic-terminal-blocks/conflicts","importantCases":"/api/acts/ad-bae-146-95-amdt-2-ceramic-terminal-blocks/important-cases","documents":"/api/acts/ad-bae-146-95-amdt-2-ceramic-terminal-blocks/documents"}}