{"id":"F2006B03508","name":"AD/BAe 146/58 - Landing Gear Brake Unit","slug":"ad-bae-146-58-landing-gear-brake-unit","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":43065,"registerId":"commonwealth-F2006B03508-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/BAe 146/58 - Landing Gear Brake Unit","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 146 Series Aeroplanes\n\nAD/BAe 146/58 Landing Gear Brake Unit 1/97\n\nApplicability: All BAe 146 and Avro 146-RJ aircraft fitted with Dunlop Carbon Brake Units which have a spacer installed.\n\nRequirement: Inspect the brake unit and set the wear remaining length of the wear indicator pin in accordance with Dunlop Mandatory Service Bulletin No. 32-1105.\n\nNote: British Aerospace Service Bulletin S.B. 32-142 refers.\n\nCompliance: Prior to 4 March 1996.\n\nBackground: The manufacturer received reports that some brakes have worn excessively causing a number of failures of the pressure stator or the adjacent rotor on brakes which have a spacer installed. To prevent such failures, this service bulletin incorporates a new procedure to find and set the wear remaining length of the wear indicator pin.","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, time-bound safety directive addressing a specific mechanical defect in a specific aircraft component. It has not expanded beyond its original purpose of preventing brake unit failures through mandatory inspection and adjustment."},"complexity_factors":["Single, specific applicability criterion (aircraft type + brake manufacturer + spacer presence)","One clear requirement referencing an external technical document (Dunlop Service Bulletin)","No defined terms section — uses standard aviation terminology","No conditional logic or nested exceptions","Single compliance date with no alternative methods or phased implementation","Extremely short — approximately 150 words total"],"plain_english_summary":"This is an **Airworthiness Directive** — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA) that requires specific maintenance action on certain aircraft.\n\n**What it does:**\nOrders owners and operators of British Aerospace BAe 146 and Avro 146-RJ aircraft to inspect their landing gear brake units and adjust a specific measurement (the \"wear remaining length\" of the wear indicator pin) on brakes made by Dunlop that contain a spacer component.\n\n**Who it affects:**\nAnyone who owns, operates, or maintains BAe 146 or Avro 146-RJ aircraft fitted with Dunlop Carbon Brake Units that have a spacer installed.\n\n**Why it matters:**\nThe manufacturer discovered that some brakes were wearing down too much, causing the pressure stator (a stationary part inside the brake) or the adjacent rotor (the rotating part) to fail. These failures could compromise the aircraft's ability to stop safely. The directive mandates a specific inspection and adjustment procedure (detailed in Dunlop Mandatory Service Bulletin No. 32-1105) to prevent these dangerous failures.\n\n**Key deadline:**\nThe work had to be completed before 4 March 1996."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The directive does not expand or narrow applicability beyond the stated group; it targets BAe 146 and Avro 146-RJ aeroplanes fitted with Dunlop Carbon Brake Units that have a spacer installed and prescribes a specific inspection/adjustment action per Dunlop Mandatory Service Bulletin No. 32-1105. The instrument’s scope remains focused on that set of aircraft and that maintenance action. (Applicability; Requirement)"},"complexity_factors":["Narrow technical scope limited to specific aircraft models and a particular brake unit configuration (Applicability)","Prescription by reference: AD requires following an external document (Dunlop Mandatory Service Bulletin No. 32-1105) rather than containing step-by-step technical instructions (Requirement)","Clear and short compliance deadline with limited regulatory discretion (Compliance)","Technical subject matter (brake wear indicator pin, pressure stator/rotor) requires specialist maintenance knowledge to implement (Background)","Cross-reference to another manufacturer service bulletin increases the number of documents operators must consult (Note)"],"plain_english_summary":"Requires operators of BAe 146 and Avro 146‑RJ aircraft fitted with Dunlop carbon brake units that include a spacer to inspect those brakes and set the wear‑indicator pin per Dunlop Mandatory Service Bulletin No. 32‑1105, to be completed by 4 March 1996.\n\nThe measure aims to prevent excessive wear that caused pressure‑stator or adjacent‑rotor failures; operators or their maintenance contractors bear the inspection/adjustment costs and must follow the service bulletin to comply."}},"importantCases":[],"_links":{"self":"/api/acts/ad-bae-146-58-landing-gear-brake-unit","history":"/api/acts/ad-bae-146-58-landing-gear-brake-unit/history","analysis":"/api/acts/ad-bae-146-58-landing-gear-brake-unit/analysis","conflicts":"/api/acts/ad-bae-146-58-landing-gear-brake-unit/conflicts","importantCases":"/api/acts/ad-bae-146-58-landing-gear-brake-unit/important-cases","documents":"/api/acts/ad-bae-146-58-landing-gear-brake-unit/documents"}}