{"id":"F2006B10905","name":"AD/JETSTREAM/37 - Brake Master Cylinder Mounting Assembly","slug":"ad-jetstream-37-brake-master-cylinder-mounting-assembly","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":56443,"registerId":"commonwealth-F2006B10905-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/JETSTREAM/37 - Brake Master Cylinder Mounting Assembly","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 - 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n \n\n![](image.001.png)  British Aerospace BAe 3100 (Jetstream) Series Aeroplanes\n\n \n\n# AD/JETSTREAM/37 Brake Master Cylinder Mounting Assembly\n\nApplicability: Model 3100 and 3200 with constructors numbers 601 to 870. Requirement:  Action in accordance with BAe Alert SB 27-A-JA 880145. Compliance:               Effective forthwith, in accordance with the Requirement Document.\n\n# 9/90 DM\n\nBackground:  There has been a report of cracking of the brake master cylinder lower mounting bracket. Failure of the bracket would result in loss of braking on the affected wheel.\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":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, targeted safety directive addressing a specific mechanical defect in a specific aircraft type. It remains precisely scoped to its original purpose of addressing the brake master cylinder mounting bracket cracking issue."},"complexity_factors":["Extremely short document (approximately 150 words)","Only 2 defined applicability criteria (model numbers and constructor numbers)","Single requirement referencing an external technical document (Service Bulletin)","No conditional logic, exceptions, or nested provisions","No cross-references to other legislation or regulations beyond the parent Civil Aviation Regulations 1998","Straightforward compliance requirement (immediate action per manufacturer bulletin)"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** issued by Australia's Civil Aviation Safety Authority (CASA) for specific British Aerospace Jetstream aircraft.\n\n**What it does:**\n- **Mandates immediate safety action** on the brake master cylinder mounting assembly for certain Jetstream 3100 and 3200 model aircraft (specifically those with construction numbers 601 to 870).\n- **Requires compliance** with a specific British Aerospace Alert Service Bulletin (SB 27-A-JA 880145) — essentially an urgent manufacturer's instruction telling operators what inspections or repairs must be done.\n\n**Who it affects:**\n- Owners and operators of British Aerospace BAe 3100 and 3200 Jetstream aircraft with serial numbers 601–870.\n- Maintenance organisations servicing these aircraft.\n\n**Why it matters:**\n- **Safety critical:** A cracked brake master cylinder mounting bracket could fail completely, causing **total loss of braking on one wheel** — a serious risk during landing or taxiing.\n- **Immediate effect:** The directive applies \"effective forthwith\" — meaning operators must act immediately, not wait for the next scheduled maintenance.\n\nIn short: CASA has ordered urgent brake inspections/repairs on specific Jetstream planes because a defect could cause brake failure."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The text sets a narrowly focused airworthiness directive applying only to BAe 3100 and 3200 aeroplanes with constructor's numbers 601–870 and requires action in accordance with a named BAe Alert. The instrument does not broaden affected types, amend other obligations, or add additional subject matter beyond addressing the brake master cylinder lower mounting bracket concern; therefore there is no indication within the supplied text that the scope has changed from its stated purpose."},"complexity_factors":["Narrow and explicit applicability (specific models and constructor's numbers). (Applicability)","Delegation of technical detail to an external Requirement Document (BAe Alert SB 27-A-JA 880145), so the directive itself is short but depends on another document. (Requirement)","Immediate compliance requirement ('effective forthwith') increases operational/administrative urgency. (Compliance)","Lack of procedural detail in the instrument means operators must obtain and interpret the separate Service Bulletin, adding an additional step to compliance.","Limited regulatory discretion in the text (mandated action tied to the Requirement Document), reducing options for alternative compliance unless provided in the SB. (Requirement; Compliance)"],"plain_english_summary":"This directive mandates immediate compliance with BAe Alert SB 27‑A‑JA 880145 for British Aerospace BAe 3100/3200 aeroplanes (constructor’s numbers 601–870) after reports of cracking in the brake master cylinder lower mounting bracket that could cause wheel brake loss.  \n\nAffected owners/operators must obtain and follow the Service Bulletin now, bearing inspection/repair costs, downtime and scheduling decisions; the directive defers technical specifics to the SB and leaves little regulatory discretion."}},"importantCases":[],"_links":{"self":"/api/acts/ad-jetstream-37-brake-master-cylinder-mounting-assembly","history":"/api/acts/ad-jetstream-37-brake-master-cylinder-mounting-assembly/history","analysis":"/api/acts/ad-jetstream-37-brake-master-cylinder-mounting-assembly/analysis","conflicts":"/api/acts/ad-jetstream-37-brake-master-cylinder-mounting-assembly/conflicts","importantCases":"/api/acts/ad-jetstream-37-brake-master-cylinder-mounting-assembly/important-cases","documents":"/api/acts/ad-jetstream-37-brake-master-cylinder-mounting-assembly/documents"}}