{"id":"F2006B03502","name":"AD/BAe 146/51 - Electrical Power Dual Lead Acid Battery Installation","slug":"ad-bae-146-51-electrical-power-dual-lead-acid-battery-installation","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":43056,"registerId":"commonwealth-F2006B03502-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/BAe 146/51 - Electrical Power Dual Lead Acid Battery Installation","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)  \nBritish Aerospace BAe 146 Series Aeroplanes\n\nAD/BAe 146/51 Electrical Power Dual Lead Acid Battery Installation\n\n  \n6/95\n\nApplicability: All BAe 146 series aircraft equipped with a dual lead-acid battery installation.\n\nNote: Dual lead-acid battery installation was introduced by BAe Modification HCM40028B or D.\n\nRequirement: Action in accordance with Avro International Aerospace Mandatory Inspection Service Bulletin S.B.24-107 dated 25 January 1995.\n\nNote: CAA(UK) AD 005-01-95 refers.\n\nCompliance: Prior to 30 June 1995.\n\nBackground: Avro International Aerospace has advised that they have received reports indicating that the two-way link between terminals \\`D8’ and \\`D9’ on terminal block \\`D’ may not be installed on some aircraft with dual lead-acid battery installations, this condition may allow premature battery discharge. This Directive ensures the aircraft wiring configuration is correct and that battery charge is preserved to meet the requirement for emergency electrical power. The CAA(UK) compliance is extended by approximately two calendar months.","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, time-limited safety directive focused on a specific wiring defect in a specific aircraft type. It has not expanded beyond its original purpose of ensuring emergency battery reliability."},"complexity_factors":["Very short document (approximately 200 words)","Only 1 substantive requirement (compliance with a specific service bulletin)","Limited applicability (single aircraft series with specific modification)","No defined terms section — technical terms are explained in context or referenced externally","No nested exceptions or conditional logic","Single compliance deadline with straightforward extension note"],"plain_english_summary":"This CASA Airworthiness Directive requires operators of BAe 146 aircraft fitted with the dual lead‑acid battery modification (HCM40028B/D) to inspect and confirm a two‑way link between terminals D8 and D9 on terminal block D per Avro Service Bulletin S.B.24‑107 (Jan 1995). Missing the link can cause premature battery discharge and loss of emergency electrical power. Compliance was required by 30 June 1995."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The AD does not broaden or repurpose the original safety objective. It remains narrowly targeted to BAe 146 aeroplanes equipped with the dual lead‑acid battery installation (per Mod HCM40028B/D) and confines required action to the inspection/correction described in Avro S.B.24‑107; no additional classes of aircraft or unrelated systems are included."},"complexity_factors":["Narrow technical scope limited to BAe 146 aircraft with dual lead‑acid battery installation (introduced by Mod HCM40028B/D)","Action depends on an external technical document (Avro Mandatory Inspection Service Bulletin S.B.24‑107) rather than full text in the AD","Specific wiring detail (terminals D8 and D9) requires qualified maintenance personnel to inspect and, if necessary, modify wiring","Fixed compliance deadline (prior to 30 June 1995) creates time pressure and scheduling burden for operators","Enforcement by the Civil Aviation Safety Authority means regulatory compliance costs fall on operators/maintenance organisations","Potential uncertainty about whether a given aircraft has the affected installation (identification/compliance checking required)"],"plain_english_summary":"This Airworthiness Directive requires operators of BAe 146 aircraft fitted with the dual lead‑acid battery installation (introduced by BAe Mod HCM40028B/D) to inspect—and if needed, correct—the two‑way link between terminal D8 and D9 in accordance with Avro Mandatory Inspection Service Bulletin S.B.24‑107 (25 Jan 1995). Compliance had to be completed prior to 30 June 1995. The directive places the inspection and any corrective work on aircraft operators or their maintenance organisations to preserve battery charge for emergency electrical power (Requirement; Compliance)."}},"importantCases":[],"_links":{"self":"/api/acts/ad-bae-146-51-electrical-power-dual-lead-acid-battery-installation","history":"/api/acts/ad-bae-146-51-electrical-power-dual-lead-acid-battery-installation/history","analysis":"/api/acts/ad-bae-146-51-electrical-power-dual-lead-acid-battery-installation/analysis","conflicts":"/api/acts/ad-bae-146-51-electrical-power-dual-lead-acid-battery-installation/conflicts","importantCases":"/api/acts/ad-bae-146-51-electrical-power-dual-lead-acid-battery-installation/important-cases","documents":"/api/acts/ad-bae-146-51-electrical-power-dual-lead-acid-battery-installation/documents"}}