{"id":"F2006B09403","name":"AD/ELECT/13 Amdt 2 - Magneto - BTH - Slow Speed Wheel - Inspection","slug":"ad-elect-13-amdt-2-magneto-bth-slow-speed-wheel-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":53755,"registerId":"commonwealth-F2006B09403-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/ELECT/13 Amdt 2 - Magneto - BTH - Slow Speed Wheel - Inspection","content":"---\nmeta-content-style-type: text/css\nmeta-content-type: application/xhtml+xml; charset=utf-8\nmeta-generator: Aspose.Words for .NET 22.10.0\n---\n\n?xml version=\"1.0\" encoding=\"utf-8\" standalone=\"no\"?>\n\nCOMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 107 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n \n\n![](image.001.png)  Electrical Equipment\n\n \n\nAD/ELECT/13\n\nAmdt 2\n\n\nMagneto - BTH - Slow Speed Wheel - Inspection 2/74\n\n \n\nApplicability: BTH Type AG4.\n\n \n\nRequirement:  Thoroughly inspect the teeth of the CX133241/1 Slow Speed Wheel for cracks or damage using at least a X5 magnifying glass. Remove from service any defective Slow Speed Wheels.\n\n \n\nCompliance: Before installation in an aircraft following each reconditioning completed after 28 February 1974.\n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":true,"description":"The instrument is labelled as Amendment 2 (Amdt 2), indicating it modifies a prior directive. The document as presented specifies applicability (BTH Type AG4), the inspection method (teeth of CX133241/1 with at least a X5 magnifier), the required action on finding defects (remove from service), and the compliance timing (before installation after any reconditioning completed after 28 February 1974). The source text does not provide the prior version’s wording, so this assessment is limited to noting that this entry is an amendment and that the current text establishes the inspection, removal and timing requirements (Applicability, Requirement, Compliance)."},"complexity_factors":["Narrow technical scope: applies only to BTH Type AG4 and CX133241/1 Slow Speed Wheel (Applicability).","Single, discrete action mandated: visual inspection for cracks/damage with a minimum X5 magnifying glass (Requirement).","Timing rule tied to reconditioning events completed after a specific historical date (Compliance), which is straightforward but specific.","Limited procedural detail: no acceptance criteria beyond 'defective', no record-keeping, no alternative methods or enforcement procedures specified (Requirement, Compliance) — this creates modest implementation ambiguity.","Operational discretion is concentrated on inspector judgment (Requirement), increasing reliance on maintenance competence rather than prescriptive testing protocols."],"plain_english_summary":"This AD mandates a visual inspection (minimum X5 magnification) of the CX133241/1 Slow Speed Wheel teeth on BTH AG4 magnetos before installing any wheel that was reconditioned after 28 Feb 1974, and requires removal from service of any wheel found defective. It affects aircraft operators, maintenance and reconditioning organisations, which must carry out and fund the inspections and any replacements."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, targeted safety directive focused on a specific mechanical defect in a specific aircraft component. It has not expanded beyond its original purpose of ensuring the airworthiness of BTH AG4 magnetos through visual inspection of the slow speed wheel."},"complexity_factors":["Extremely short document (under 200 words)","Only 1 defined term implicitly referenced (the part number CX133241/1)","Single, unambiguous requirement with no conditional branches or exceptions","No cross-references to other legislation or regulations","Clear, direct compliance date and trigger (reconditioning after specific date)","Straightforward applicability statement (single equipment type)"],"plain_english_summary":"This is an **Airworthiness Directive** — a mandatory safety instruction issued by Australia's Civil Aviation Safety Authority (CASA) that requires aircraft owners and mechanics to take specific action to fix a known safety problem.\n\n**What it does:**\n- Targets a specific aircraft engine part: the **BTH Type AG4 magneto** (a device that generates electrical current for the engine's ignition system)\n- Requires inspection of a particular component inside this magneto — the \"CX133241/1 Slow Speed Wheel\" — using at least a 5x magnifying glass\n- Mandates that any cracked or damaged wheels must be removed from service immediately\n\n**Who it affects:**\n- Aircraft maintenance engineers and repair stations who work on or recondition BTH Type AG4 magnetos\n- Aircraft operators whose planes use this specific magneto type\n\n**Why it matters:**\nCracks in the slow speed wheel can cause magneto failure, which means the engine could lose ignition and stop working — a serious safety risk in flight. This directive ensures defective parts are caught before they get back into an aircraft.\n\n**When compliance is required:**\nEvery time one of these magnetos is reconditioned (overhauled/repaired) after 28 February 1974, the inspection must be done **before** the magneto goes back into an aircraft."}},"importantCases":[],"_links":{"self":"/api/acts/ad-elect-13-amdt-2-magneto-bth-slow-speed-wheel-inspection","history":"/api/acts/ad-elect-13-amdt-2-magneto-bth-slow-speed-wheel-inspection/history","analysis":"/api/acts/ad-elect-13-amdt-2-magneto-bth-slow-speed-wheel-inspection/analysis","conflicts":"/api/acts/ad-elect-13-amdt-2-magneto-bth-slow-speed-wheel-inspection/conflicts","importantCases":"/api/acts/ad-elect-13-amdt-2-magneto-bth-slow-speed-wheel-inspection/important-cases","documents":"/api/acts/ad-elect-13-amdt-2-magneto-bth-slow-speed-wheel-inspection/documents"}}