{"id":"F2006B10426","name":"AD/HS 125/146 - Instrument Panel Lighting","slug":"ad-hs-125-146-instrument-panel-lighting","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":116115,"registerId":"commonwealth-F2006B10426-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/HS 125/146 - Instrument Panel Lighting","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 125 Series Aeroplanes\n\nAD/HS 125/146 Instrument Panel Lighting 2/95\n\nDM\n\nApplicability: Raytheon Corporate Jets BAe 125 Series 1000A and 1000B aircraft identified in Raytheon Corporate Jets Mandatory Service Bulletin SB.33-52-25A800A&B dated 16 November 1994.\n\nRequirement: Action in accordance with Raytheon Corporate Jets Mandatory Service Bulletin SB.33-52-25A800A&B dated 16 November 1994.\n\nNote: CAA(UK) AD 002-11-94 refers.\n\nCompliance: Prior to 12 January 1995.\n\nBackground: Raytheon has reported that an instrument panel lighting balance unit has overheated in flight allowing the emission of smoke into the flight deck area. This Directive requires the temporary revision of the lighting balance system to the pre modification condition. The CAA(UK) compliance is extended by one calendar month.","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The Directive’s scope is limited to the BAe 125 Series 1000A and 1000B aircraft identified in the referenced Raytheon Mandatory Service Bulletin and to the temporary revision of the instrument panel lighting balance system to the pre-modification condition. The text does not indicate an expansion or narrowing beyond that stated applicability and requirement."},"complexity_factors":["Reliance on an external technical document (Raytheon Mandatory Service Bulletin SB.33-52-25A800A&B) for the actual corrective steps","A firm compliance deadline (prior to 12 January 1995) requiring scheduling and possible aircraft downtime","Requirement to revert to a prior (pre-modification) configuration, which may have operational consequences not described in the AD","Cross-jurisdictional reference (CAA(UK) AD) and differing compliance timelines (UK extension noted)","Limited information in the AD itself about technical details, parts, or inspection criteria"],"plain_english_summary":"This AD requires operators of the Raytheon BAe 125 Series 1000A/1000B aircraft (as listed in Raytheon Mandatory Service Bulletin SB.33-52-25A800A&B) to follow that service bulletin to temporarily revert the instrument-panel lighting balance system to its pre‑modification configuration before 12 January 1995. It was issued after overheating allowed smoke into the flight deck; operators bear labour, downtime and parts costs. The UK CAA has a one‑month extended compliance allowance."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, time-limited safety directive addressing a specific technical fault in specific aircraft. It has not expanded beyond its original purpose of mandating a temporary fix for an overheating instrument panel component."},"complexity_factors":["Very short document (under 200 words)","Only 1 defined term implicitly referenced (the service bulletin)","Single, unambiguous compliance action (follow the service bulletin)","No nested conditions or exceptions","Clear applicability criteria (specific aircraft models)","Single cross-reference to UK CAA AD for context"],"plain_english_summary":"**What this is:** This is an Airworthiness Directive (AD) — essentially a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA) for specific aircraft.\n\n**What it does:** It requires owners or operators of certain British Aerospace BAe 125 series business jets (specifically the 1000A and 1000B models) to carry out a specific safety fix on their instrument panel lighting system.\n\n**The safety problem:** Raytheon (the manufacturer) reported that a component called a \"lighting balance unit\" in the instrument panel had overheated during flight, causing smoke to enter the cockpit. That's obviously dangerous — smoke in the cockpit can impair pilot vision and create panic or emergency situations.\n\n**What must be done:** Aircraft operators must follow the instructions in Raytheon's Mandatory Service Bulletin SB.33-52-25A800A&B (dated 16 November 1994). This involves temporarily reverting the lighting balance system back to its pre-modification state — essentially undoing a previous change until a permanent fix is developed.\n\n**Who it affects:** Operators of the specific BAe 125-1000A and 1000B aircraft listed in the service bulletin.\n\n**When it had to be done:** Before 12 January 1995 (the directive extends a UK deadline by one month).\n\n**Why it matters:** This is a reactive safety measure to prevent in-flight smoke events that could distract pilots, reduce visibility of critical instruments, or escalate into fire. Airworthiness Directives are legally binding — failure to comply means the aircraft cannot legally fly."}},"importantCases":[],"_links":{"self":"/api/acts/ad-hs-125-146-instrument-panel-lighting","history":"/api/acts/ad-hs-125-146-instrument-panel-lighting/history","analysis":"/api/acts/ad-hs-125-146-instrument-panel-lighting/analysis","conflicts":"/api/acts/ad-hs-125-146-instrument-panel-lighting/conflicts","importantCases":"/api/acts/ad-hs-125-146-instrument-panel-lighting/important-cases","documents":"/api/acts/ad-hs-125-146-instrument-panel-lighting/documents"}}