{"id":"F2006B02276","name":"AD/AL 250/65 - Engine Power and Accessory Gearbox - New Magnetic Plug Introduction","slug":"ad-al-250-65-engine-power-and-accessory-gearbox-new-magnetic-plug-introduction","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":41506,"registerId":"commonwealth-F2006B02276-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/AL 250/65 - Engine Power and Accessory Gearbox - New Magnetic Plug Introduction","content":"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 106 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n![](image.001.png)  \nAllison Turbine Engines \\- 250 Series\n\nAD/AL 250/65 Engine Power and Accessory Gearbox \\- New\n\nMagnetic Plug Introduction\n\n  \n4/85\n\nApplicability: Model 250-C30 and C30S engines (and power and accessory gearboxes) installed in or intended for installation in S-76 Helicopters and which incorporate magnetic plug P/N 23001915.\n\nRequirement: Fit new magnetic plugs P/N 6871534 in lieu of old plugs P/N 23001915.\n\nAllison 250-C30, C30S CEB-A-72-3098 Revision 1.\n\nCompliance: 1. For installed Engine/gearbox assemblies:\n\nUnless already accomplished, prior to issue of the next Maintenance Release after 30 April 1985.\n\n2. For uninstalled engines, power and accessory gearboxes, housings and covers: Prior to installation in an aircraft.\n\nBackground: In service experience with automatic fuzz burn off magnetic plugs P/N 23001915 has indicated that early detection of oil system contamination is being lost due to the effectiveness of the fuzz burn off feature.\n\nCEB-A-72-3098 replaces the auto fuzz burn off plug with the 6871534 plug which is currently fitted to the 250-C20 engine and has proven to be reliable in providing an early indication of engine or gearbox oil contamination.","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The directive preserves a narrow, equipment‑specific scope: it replaces a particular magnetic plug on specified engine models in S‑76 helicopters and sets clear compliance timing. It does not broaden affected models, operations, or regulatory reach beyond the stated applicability and replacement requirement."},"complexity_factors":["Narrow technical scope — applies only to Allison 250‑C30 and C30S engines/gearboxes in S‑76 helicopters (clear applicability).","Single, specific hardware swap (P/N 23001915 -> P/N 6871534) reduces interpretive complexity.","Two simple compliance deadlines: installed units by next Maintenance Release after 30/4/1985; uninstalled parts before installation.","Requires maintenance action and tracking in operator maintenance releases — operational scheduling burden for operators.","Reference to manufacturer service bulletin (CEB‑A‑72‑3098 Rev 1) creates a documentary dependency for method/details."],"plain_english_summary":"This Airworthiness Directive requires operators of Allison 250‑C30 and C30S engines (and their power/accessory gearboxes) installed in, or intended for, S‑76 helicopters to replace magnetic plug P/N 23001915 with P/N 6871534. Installed units must be modified by the next Maintenance Release after 30 April 1985; uninstalled parts must be fitted with the new plug before installation. The change restores early oil‑contamination detection lost because the old plug’s \"fuzz burn off\" feature masked contamination; operators pay and must schedule the replacement."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, targeted safety directive addressing a specific technical defect identified in service. It has not expanded beyond its original purpose of mandating a part replacement to improve oil contamination detection."},"complexity_factors":["Single, specific technical requirement (replace one part with another)","Only 2 defined part numbers and 2 engine models affected","Clear applicability criteria (S-76 helicopters, specific P/N)","Simple binary compliance structure (installed vs uninstalled equipment)","No cross-references to other legislation beyond the enabling Civil Aviation Regulations 1998","No conditional exceptions or nested provisions","Background explanation provided in plain technical language"],"plain_english_summary":"This AD requires replacing magnetic plug 23001915 with plug 6871534 in Allison 250‑C30 and C30S engines used in S‑76 helicopters. It affects operators and maintenance organisations responsible for these engines, gearboxes and housings. The swap removes an “automatic fuzz burn off” feature that was removing metal particles inspectors rely on, so the new plugs make metal contamination visible earlier and help prevent engine or gearbox failure. Compliance: before the next Maintenance Release after 30 April 1985 or before installing spares."}},"importantCases":[],"_links":{"self":"/api/acts/ad-al-250-65-engine-power-and-accessory-gearbox-new-magnetic-plug-introduction","history":"/api/acts/ad-al-250-65-engine-power-and-accessory-gearbox-new-magnetic-plug-introduction/history","analysis":"/api/acts/ad-al-250-65-engine-power-and-accessory-gearbox-new-magnetic-plug-introduction/analysis","conflicts":"/api/acts/ad-al-250-65-engine-power-and-accessory-gearbox-new-magnetic-plug-introduction/conflicts","importantCases":"/api/acts/ad-al-250-65-engine-power-and-accessory-gearbox-new-magnetic-plug-introduction/important-cases","documents":"/api/acts/ad-al-250-65-engine-power-and-accessory-gearbox-new-magnetic-plug-introduction/documents"}}