{"id":"F2006B10424","name":"AD/HS 125/144 - Elevator Pulley Assembly","slug":"ad-hs-125-144-elevator-pulley-assembly","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":116111,"registerId":"commonwealth-F2006B10424-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/HS 125/144 - Elevator Pulley 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 125 Series Aeroplanes\n\n \n\nAD/HS 125/144 Elevator Pulley Assembly 11/94\n\nApplicability: Model BAe Series 1000A and B, and Hawker 1000 aircraft as identified in the Requirement Document.\n\n \n\nRequirement: Action in accordance with Hawker Raytheon Corporate Jets Mandatory Service Bulletin 27-161.\n\n \n\nCompliance: Prior to 31 March 1995.\n\n \n\nBackground: The manufacturer had received reports of incorrectly assembled elevator pulley installations on some in-service aircraft.\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, time-bound safety directive addressing a specific mechanical defect in specific aircraft. It has not expanded beyond its original purpose of mandating a single corrective action."},"complexity_factors":["Extremely short document — only 6 substantive lines of regulatory text","No defined terms section — all language is plain technical aviation terminology","Single, unambiguous compliance requirement (follow one specific service bulletin)","No cross-references to other legislation or regulations beyond the parent Civil Aviation Regulations 1998","No conditional logic, exceptions, or nested requirements","Clear applicability statement limiting scope to specific aircraft models"],"plain_english_summary":"This is an **Airworthiness Directive** — essentially a safety order issued by Australia's Civil Aviation Safety Authority (CASA) that requires specific aircraft owners and operators to fix a mechanical problem.\n\n**What it does:**\n- Orders owners of specific British Aerospace BAe 125 series business jets (models 1000A, 1000B, and Hawker 1000) to inspect and correct a defect in the **elevator pulley assembly** — that's a component in the tail section that helps control the aircraft's pitch (up and down movement).\n\n**Why it matters:**\n- The manufacturer discovered that some aircraft had **incorrectly assembled elevator pulleys** installed. This is serious because the elevator controls whether the plane's nose goes up or down; if the pulley system fails, the pilot could lose control of the aircraft's pitch, potentially leading to a crash.\n\n**Who must act:**\n- Operators of the specific aircraft models listed above.\n\n**What they must do:**\n- Follow the manufacturer's mandatory service bulletin (technical repair instructions) numbered 27-161.\n\n**Deadline:**\n- The work had to be completed before 31 March 1995.\n\nIn short: CASA found out some business jets had a potentially dangerous assembly error in their flight controls, and ordered the owners to get it fixed by a specific deadline."},"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The AD's scope is consistent with the document's stated purpose: it targets the specific aircraft models identified and mandates the corrective actions described in the manufacturer’s Mandatory Service Bulletin to address reported incorrect elevator pulley assemblies (Applicability; Requirement; Background). There is no indication in the text that the AD broadened or narrowed its intended set of affected aircraft or required actions beyond that stated purpose."},"complexity_factors":["Narrow technical scope: applies to specific BAe 125 Series 1000A/B and Hawker 1000 aircraft (Applicability)","Directive delegates technical detail to an external Mandatory Service Bulletin, requiring the operator to obtain and follow that document (Requirement)","Fixed and near-term compliance deadline that creates scheduling urgency but is administratively simple to check (Compliance)","Safety‑critical mechanical component (elevator pulley assembly) requiring competent maintenance, which raises practical implementation complexity though not legal complexity (Background)","Limited regulatory discretion within the text — the AD is prescriptive rather than setting broad, open‑ended duties (Requirement)"],"plain_english_summary":"This directive requires operators of specified British Aerospace BAe 125 Series 1000A/1000B and Hawker 1000 aircraft to carry out the maintenance actions in Hawker Raytheon Corporate Jets Mandatory Service Bulletin 27‑161 by 31 March 1995, after reports of incorrectly assembled elevator pulley installations. CASA issued the AD under Part 39, making compliance compulsory; operators bear the inspection, repair and downtime costs and have limited scope to use alternative technical methods without regulator approval."}},"importantCases":[],"_links":{"self":"/api/acts/ad-hs-125-144-elevator-pulley-assembly","history":"/api/acts/ad-hs-125-144-elevator-pulley-assembly/history","analysis":"/api/acts/ad-hs-125-144-elevator-pulley-assembly/analysis","conflicts":"/api/acts/ad-hs-125-144-elevator-pulley-assembly/conflicts","importantCases":"/api/acts/ad-hs-125-144-elevator-pulley-assembly/important-cases","documents":"/api/acts/ad-hs-125-144-elevator-pulley-assembly/documents"}}