{"id":"F2006B03136","name":"AD/B747/238 - Hydraulic Brake Accumulators","slug":"ad-b747-238-hydraulic-brake-accumulators","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":42508,"registerId":"commonwealth-F2006B03136-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"AIRWORTHINESS DIRECTIVE","sectionType":"part","heading":"AIRWORTHINESS DIRECTIVE","content":"# AIRWORTHINESS DIRECTIVE\n\n![](image.002.png)\n\n![](image.002.png)  \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 CAR 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.","sortOrder":0},{"sectionNumber":"AD/B747/238 Hydraulic Brake Accumulators","sectionType":"part","heading":"AD/B747/238 Hydraulic Brake Accumulators 13/2000","content":"# AD/B747/238 Hydraulic Brake Accumulators 13/2000\n\nApplicability: Model 747 series aeroplanes; as listed in Boeing Special Attention Service Bulletin 747-32-2461, dated August 19, 1999.\n\nRequirement: 1\\. Replace all brake system accumulators which have aluminium end caps with accumulators which have stainless steel end caps in accordance with Boeing Special Attention Service Bulletin 747-32-2461.\n\n2. A Part Number (P/N) BACA11E1 (Parker P/N 2660472-1 or 2660472M1) or BACA11E5 (Parker P/N 2660472-5 or 2660472M5) brake system accumulator must not be installed as a replacement item on an aeroplane applicable to this Airworthiness Directive.\n\nNote: FAA Airworthiness Directive 2000-14-01 Amendment 39-11810 refers.\n\nCompliance: 1. Unless previously accomplished, at the next “C”-check but not to exceed 6000 flight hours from the effective date of this Airworthiness Directive.\n\n2. From the effective date of this Airworthiness Directive.\n\nThis Airworthiness Directive becomes effective on 28 December 2000.\n\nBackground: There have been ten cases of brake accumulator aluminium end cap fracture that may result in high velocity separation which could cause injury to personnel in the wheel well area, loss of cabin pressurisation, loss of certain hydraulic systems or damage the fuel line of the auxiliary power unit.\n\n![Signature of Eugene Paul Holzapfel, Delegate of the Civil Aviation Safety Authority.](image.003.png)  \n\nEugene Paul Holzapfel\n\nDelegate of the Civil Aviation Safety Authority 13 November 2000\n\n![](image.002.png)  \n\nThe above AD is notified in the Commonwealth of Australia Gazette on 22 November 2000","sortOrder":1}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This Airworthiness Directive maintains its original narrow scope. It addresses a specific mechanical defect in a specific aircraft type (Boeing 747 brake accumulators) and mandates a specific replacement. There is no evidence of scope creep; the directive remains tightly focused on the safety issue identified in the background section."},"complexity_factors":["Very short document (approximately 300 words)","Only 2 substantive requirements with clear mechanical actions","Single applicability criterion referencing an external Boeing document","Simple compliance timeline with two alternative deadlines","No defined terms section or interpretation provisions","No nested exceptions or conditional logic","Straightforward cause-and-effect: unsafe part identified → replacement mandated"],"plain_english_summary":"Australia’s aviation regulator (CASA) orders airlines and maintenance organisations operating affected Boeing 747s to replace brake accumulators with aluminium end caps—which have fractured in 10 cases—with stainless‑steel‑capped units, and immediately bans installing specified part numbers (BACA11E1/BACA11E5 variants). Compliance is required by the next C‑check or within 6,000 flight hours, whichever comes first. This reduces a real risk of high‑speed failures that can injure personnel and damage aircraft systems."},"flash_summary_failed":{"failed":true,"reason":"A positive credit balance is required for all requests, including BYOK, so fallback providers remain available. Add credits at https://vercel.com/d?to=%2F%5Bteam%5D%2F%7E%2Fai%3Fmodal%3Dtop-up to continue.","source":"analysis-cron"},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The directive targets the specific unsafe condition described (aluminium end-cap fractures) on the Boeing 747s listed in the referenced Boeing service bulletin and requires a single corrective action plus a parts ban; it does not expand applicability or obligations beyond that defined corrective scope."},"complexity_factors":["Narrow technical remedy: replace aluminium end caps with stainless steel end caps (single corrective action).","Explicit prohibited replacement part numbers (specific Parker P/Ns listed).","Applicability limited to Boeing 747 models as identified in Boeing Special Attention Service Bulletin 747-32-2461.","Compliance timing tied to scheduled maintenance (‘C’-check) or a firm flight-hour limit (6000 hours).","Safety-critical consequences explicitly described (high-velocity separation, injury, depressurisation, hydraulic or APU fuel-line damage).","Issued and enforceable under CAR 1998 subregulation 39.1(1) by a CASA delegate (administrative enforcement pathway)."],"plain_english_summary":"This Airworthiness Directive requires operators of Boeing 747 variants listed in Boeing Special Attention Service Bulletin 747-32-2461 to replace brake accumulators with aluminium end caps with units that have stainless steel end caps, and forbids installing specific Parker part numbers as replacements. Compliance must occur at the next “C”-check or within 6000 flight hours. CASA cites ten aluminium end‑cap fractures that could cause injury, depressurisation, hydraulic system loss or APU fuel‑line damage; operators bear replacement and scheduling costs, and the CASA delegate enforces compliance."}},"importantCases":[],"_links":{"self":"/api/acts/ad-b747-238-hydraulic-brake-accumulators","history":"/api/acts/ad-b747-238-hydraulic-brake-accumulators/history","analysis":"/api/acts/ad-b747-238-hydraulic-brake-accumulators/analysis","conflicts":"/api/acts/ad-b747-238-hydraulic-brake-accumulators/conflicts","importantCases":"/api/acts/ad-b747-238-hydraulic-brake-accumulators/important-cases","documents":"/api/acts/ad-b747-238-hydraulic-brake-accumulators/documents"}}