{"id":"F2006B08430","name":"AD/CESSNA 550/24 - BFGoodrich Brake Stator Discs","slug":"ad-cessna-550-24-bfgoodrich-brake-stator-discs","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":115911,"registerId":"commonwealth-F2006B08430-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"AIRWORTHINESS DIRECTIVE","sectionType":"part","heading":"AIRWORTHINESS DIRECTIVE","content":"# AIRWORTHINESS DIRECTIVE\n\n![](image.001.png)\n\nFor the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (AD) under subregulation 39.1 (1) of CASR 1998. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.\n\n![](image.001.png)  \n\nCessna 550 (Citation II) Series Aeroplanes","sortOrder":0},{"sectionNumber":"AD/CESSNA 550/24 BFGoodrich Brake Stator","sectionType":"part","heading":"AD/CESSNA 550/24 BFGoodrich Brake Stator Discs 7/2004","content":"# AD/CESSNA 550/24 BFGoodrich Brake Stator Discs 7/2004\n\nApplicability: Model 550 and 551 aircraft, serial numbers 0002 through 0733; equipped with BFGoodrich brake assembly part number 2-1528-6 or 2-1530-4.\n\nRequirement: Inspect in accordance with the requirements of FAA AD 2004-09-05 Amdt 39-13594.\n\nNote: BFGoodrich Service Bulletins 2-1528-32-3 and 2-1530-32-3, both original issue, and Goodrich Service Bulletins 2-1528-32-2 and 2-1530-32-2, both Revision 5, refer.\n\nCompliance: Within 50 landings or 90 days after 8 July 2004, whichever occurs first, for the initial inspection. As specified in the Requirement document for other compliance times, with a revised effective date of 8 July 2004.\n\nThis Airworthiness Directive becomes effective on 8 July 2004.\n\nBackground: The FAA requires a one-time inspection of the brake stator discs to determine to what change level they have been modified (if any), and related actions if necessary. This Directive also requires that the existing markings on the piston housing of certain brake assemblies be eliminated. The actions required by this Directive are intended to prevent wheel lock-ups that may be caused by cracked or broken brake stator discs becoming jammed in the brake assembly and preventing rotation. Such jamming may result in reduced directional control or braking performance during landing.\n\n![Signature of David Villiers Delegate of the Civil Aviation Safety Authority](image.002.png)  \n\nDavid Villiers\n\nDelegate of the Civil Aviation Safety Authority 28 May 2004\n\n![](image.001.png)","sortOrder":1}],"analysis":{"flash_summary_failed":{"failed":true,"reason":"Unauthenticated. Configure AI_GATEWAY_API_KEY or use a provider module. Learn more: https://ai-sdk.dev/unauthenticated-ai-gateway","source":"analysis-cron"},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a standard airworthiness directive with a narrow, specific scope — addressing a known safety defect in particular brake assemblies on specific aircraft models. It has not expanded beyond its original purpose of mandating inspection and marking removal to prevent brake failures."},"complexity_factors":["Very short document (approximately 300 words)","Only 2 defined applicability criteria (aircraft models/serial numbers and brake part numbers)","Single cross-reference to an external FAA document (AD 2004-09-05) for detailed requirements","Simple compliance structure with one initial deadline and reference to external document for subsequent deadlines","No nested exceptions or conditional logic beyond the applicability criteria","Background section provides clear safety rationale in plain language"],"plain_english_summary":"Owners/operators of Cessna Citation II (models 550/551, S/N 0002–0733) with specified BFGoodrich brake assemblies must inspect brake stator discs per FAA AD 2004‑09‑05, and remove certain piston‑housing markings if those assemblies are fitted. The inspections (initial within 50 landings or 90 days after 8 July 2004) address cracked/broken stator discs that can jam brakes and cause wheel lock‑ups or loss of directional control on landing."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The Directive adopts the FAA-required one-time inspection and related actions and adds removal of existing piston-housing markings; it does not expand the affected fleet or introduce broader recurring obligations beyond those referenced, so scope aligns with the stated FAA-based requirement."},"complexity_factors":["Narrow applicability: specific aircraft models, serial number range (0002–0733) and specific part numbers (2-1528-6, 2-1530-4) restrict who must act.","Cross-references to external documents: Requirement relies on FAA AD 2004-09-05 and multiple BFGoodrich/Goodrich service bulletins, requiring readers to consult other texts to know exact inspection steps.","Time-based compliance metric: initial deadline uses either 50 landings or 90 days from 8 July 2004, requiring operators to track landing counts and calendar time.","Additional non-inspection action: elimination of existing piston-housing markings adds a discrete removal step beyond inspection.","Operational impact risk: potential for required repairs or part replacement if defects found, creating operator costs, scheduling/downtime and parts-supply considerations."],"plain_english_summary":"This AD requires operators of Cessna 550/551 aircraft (serials 0002–0733) fitted with BFGoodrich brake assemblies P/N 2-1528-6 or 2-1530-4 to perform a one‑time inspection of brake stator discs and remove certain piston‑housing markings, following FAA AD 2004‑09‑05 and referenced service bulletins. The initial inspection must occur within 50 landings or 90 days of 8 July 2004. The stated purpose is to prevent wheel lock‑ups from cracked or broken stator discs; operators bear inspection, repair and downtime costs."}},"importantCases":[],"_links":{"self":"/api/acts/ad-cessna-550-24-bfgoodrich-brake-stator-discs","history":"/api/acts/ad-cessna-550-24-bfgoodrich-brake-stator-discs/history","analysis":"/api/acts/ad-cessna-550-24-bfgoodrich-brake-stator-discs/analysis","conflicts":"/api/acts/ad-cessna-550-24-bfgoodrich-brake-stator-discs/conflicts","importantCases":"/api/acts/ad-cessna-550-24-bfgoodrich-brake-stator-discs/important-cases","documents":"/api/acts/ad-cessna-550-24-bfgoodrich-brake-stator-discs/documents"}}