{"id":"F2006B09187","name":"AD/DHC-8/31 - Firewall Electrical Terminal Block","slug":"ad-dhc-8-31-firewall-electrical-terminal-block","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":52978,"registerId":"commonwealth-F2006B09187-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/DHC-8/31 - Firewall Electrical Terminal Block","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)  \nBombardier (Boeing Canada/De Havilland) DHC-8 Series Aeroplanes\n\nAD/DHC-8/31 Firewall Electrical Terminal Block 4/94\n\nDM\n\nApplicability: DHC-8 aircraft, models 102, 103, 106, 301, 311 and 314, serial numbers 003 through\n\n362 inclusive.\n\nRequirement: Incorporate de Havilland Modification 8/1984 in accordance with Bombardier Regional Aircraft Division de Havilland Dash 8 Service Bulletin S.B.8-24-47 Revision A dated 29 November 1993.\n\nNote: Transport Canada AD CF-93-31 dated 17 December 1993 refers.\n\nCompliance: Prior to 23 April 1994.\n\nBackground: Results from a de Havilland investigation show that the use of aluminium washers in the DC firewall terminal block and battery shunt cable assemblies can cause corrosion at the electrical connections. This can result in either a loose connection or generate a high electrical resistance at the connection point. Compliance with this Directive is designed to prevent the corrosion occurring. Compliance required by Transport Canada is extended by 30 days.","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, time-bound safety directive addressing a specific technical defect. It has not expanded beyond its original purpose of mandating a single corrosion-prevention modification."},"complexity_factors":["Single, specific technical requirement with clear reference to manufacturer service bulletin","Limited applicability (6 specific models, defined serial number range)","No nested exceptions or conditional logic","Single compliance deadline with straightforward 30-day extension note","Only one defined term implicitly used (the modification reference)","Short document (approximately 150 words excluding header)"],"plain_english_summary":"This AD mandates a factory modification on certain de Havilland DHC-8 (Dash 8) aircraft to eliminate corroding aluminium washers in firewall-area electrical connections. It affects specific serial-numbered aircraft and their maintenance organizations and must be accomplished per the issued service instructions by 23 April 1994. The change prevents loose, high-resistance connections that could lead to fires or electrical failures."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"Scope remains focused on preventing corrosion at firewall DC terminal and shunt cable connections for the listed DHC‑8 models/serials by mandating a specified modification via the cited service bulletin. The only timing change noted is a 30‑day extension relative to Transport Canada's AD (Note)."},"complexity_factors":["Narrow applicability: specific models and serial numbers listed (Applicability)","Prescriptive technical action: requires incorporation of a named modification via a specific service bulletin (Requirement)","Fixed compliance deadline with potential operational impacts (Compliance)","Cross-reference to foreign regulator AD (Transport Canada) and a stated 30‑day extension (Note)","Practical compliance burden: parts replacement, labour, inspection and potential grounding (implied by Requirement/Background)"],"plain_english_summary":"This Airworthiness Directive requires owners/operators of specified De Havilland/Bombardier DHC‑8 aeroplanes (models 102, 103, 106, 301, 311, 314; serials 003–362) to install de Havilland Modification 8/1984 by following Bombardier Service Bulletin S.B.8‑24‑47 Revision A to eliminate aluminium washers in firewall DC terminal blocks and battery shunt assemblies (Requirement; Background). The stated aim is to prevent corrosion that can cause loose or high‑resistance electrical connections; operators must comply by 23 April 1994, bearing the costs and possible downtime (Compliance; Note)."}},"importantCases":[],"_links":{"self":"/api/acts/ad-dhc-8-31-firewall-electrical-terminal-block","history":"/api/acts/ad-dhc-8-31-firewall-electrical-terminal-block/history","analysis":"/api/acts/ad-dhc-8-31-firewall-electrical-terminal-block/analysis","conflicts":"/api/acts/ad-dhc-8-31-firewall-electrical-terminal-block/conflicts","importantCases":"/api/acts/ad-dhc-8-31-firewall-electrical-terminal-block/important-cases","documents":"/api/acts/ad-dhc-8-31-firewall-electrical-terminal-block/documents"}}