{"id":"F2006B03485","name":"AD/BAe 146/33 - Pitot-Static System","slug":"ad-bae-146-33-pitot-static-system","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":43039,"registerId":"commonwealth-F2006B03485-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/BAe 146/33 - Pitot-Static System","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 146 Series Aeroplanes\n\n \n\nAD/BAe 146/33 Pitot-Static System 7/91\n\nApplicability: All series 200 and 200A Constructor’ Nos E2164 and subsequent, and all series 300 and 300A Constructor’s Nos E3118, E3163 and subsequent.\n\n \n\nRequirement: Action in accordance with Mandatory British Aerospace Service Bulletin 34-128- 00950J.\n\n \n\nCompliance: Prior to 31 July 1991.\n\n \n\nBackground: It has been found that water traps form in the hoses fitted to post Mod. HCM 00950A&D (introduction of EFIS) 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":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The directive as presented limits action to specified BAe 146 series and Constructor’s numbers and prescribes compliance with a named Mandatory Service Bulletin by a set date. The instrument does not indicate any change in that scope from an earlier statement within this text; therefore there is no evidence here that the scope has been expanded or narrowed relative to the directive’s stated applicability and requirements."},"complexity_factors":["Narrow, well-defined applicability by series and constructor (serial) numbers reduces scope complexity (Applicability).","Prescriptive requirement references an external Mandatory Service Bulletin rather than detailing work in the directive, requiring operators to obtain and follow another technical document (Requirement).","Hard compliance deadline creates an urgent scheduling requirement for affected operators (Compliance).","Technical subject matter (pitot-static system hoses, water traps) requires specialised maintenance skills and access to OEM technical instructions (Background; Requirement).","The directive excerpt does not include enforcement detail, post-action verification steps, or alternative compliance paths in the text provided, which can create practical uncertainty for operators about acceptance/administration."],"plain_english_summary":"Requires operators of specified BAe 146 Series 200/200A (Constructor’s Nos E2164+) and Series 300/300A (Nos E3118, E3163+) to carry out Mandatory British Aerospace Service Bulletin 34-128-00950J to remedy water traps found in hoses after Mod. HCM 00950A&D. Work must be completed prior to 31 July 1991; operators/owners pay for and schedule the work, enforced by CASA via the Airworthiness Directive."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, time-bound safety directive addressing a specific technical defect in specific aircraft. It has not expanded beyond its original purpose of mandating a particular inspection/repair."},"complexity_factors":["Very short document (approximately 150 words)","Only 4 defined elements: applicability by aircraft series and constructor numbers, single mandatory service bulletin reference, single compliance date, and brief background explanation","No cross-references to other legislation or regulations beyond the parent Civil Aviation Regulations 1998","No conditional logic or exceptions — straightforward mandatory action","Single operational requirement with clear deadline","Technical content limited to aircraft model identification and manufacturer bulletin reference"],"plain_english_summary":"**What this is:** This is an **Airworthiness Directive (AD)** — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA) that requires aircraft owners or operators to fix a specific safety problem.\n\n**What it does:** It orders operators of certain **British Aerospace BAe 146 aircraft** (specifically Series 200, 200A, 300, and 300A models built after certain serial numbers) to inspect and repair their **pitot-static system** — the network of tubes and sensors that measure airspeed, altitude, and vertical speed. These measurements are critical for safe flight.\n\n**The problem:** Water was collecting in hoses within the pitot-static system on aircraft that had been modified with electronic flight instrument systems (EFIS). This water could freeze at altitude and block the sensors, giving pilots false readings — a dangerous situation.\n\n**What must be done:** Operators must follow the specific repair instructions in **British Aerospace Service Bulletin 34-128-00950J** — a technical manual from the manufacturer detailing the fix.\n\n**Deadline:** The work had to be completed **before 31 July 1991**.\n\n**Who it affects:** Airlines and operators flying the specified BAe 146 aircraft in Australia.\n\n**Why it matters:** Faulty airspeed or altitude readings can lead to catastrophic accidents. This directive prevents that by ensuring water cannot accumulate and freeze in the system."}},"importantCases":[],"_links":{"self":"/api/acts/ad-bae-146-33-pitot-static-system","history":"/api/acts/ad-bae-146-33-pitot-static-system/history","analysis":"/api/acts/ad-bae-146-33-pitot-static-system/analysis","conflicts":"/api/acts/ad-bae-146-33-pitot-static-system/conflicts","importantCases":"/api/acts/ad-bae-146-33-pitot-static-system/important-cases","documents":"/api/acts/ad-bae-146-33-pitot-static-system/documents"}}