{"id":"F2006B02398","name":"AD/AMD 50/31 - Hydraulic Line Chafing","slug":"ad-amd-50-31-hydraulic-line-chafing","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":41641,"registerId":"commonwealth-F2006B02398-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"AIRWORTHINESS DIRECTIVE","sectionType":"part","heading":"AIRWORTHINESS DIRECTIVE","content":"# ![](image.001.png)  \nAIRWORTHINESS DIRECTIVE\n\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 CASR 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.\n\n![](image.001.png)  \n\nAMD Falcon 50 and 900 Series Aeroplanes","sortOrder":0},{"sectionNumber":"AD/AMD 50/31 Hydraulic Line Chafing 7/20","sectionType":"part","heading":"AD/AMD 50/31 Hydraulic Line Chafing 7/2003 TX","content":"# AD/AMD 50/31 Hydraulic Line Chafing 7/2003 TX\n\nApplicability: Dassault Aviation Mystere Falcon 50 aeroplanes with serial numbers 2 though 329 inclusive.\n\nRequirement: 1. Carry out an inspection and measurement of the hydraulic lines in accordance with Dassault Aviation Service Bulletin (S/B) F50-A370.\n\n    2. Replace any chafed hydraulic lines as detailed in the replacement criteria of Dassault Aviation S/B F50-A370.\n    3. Ensure that the hydraulic lines as detailed in Dassault Aviation Service Bulletin S/B F50-A370 are fitted in accordance with Dassault Aviation Service Bulletin S/B F50-A370.\n    4. Incorporate temporary revision F50-WC-844.0/1 into the Airframe Maintenance Manual.\n\nNote: DGAC Telex AD T2003-190(B) refers.\n\nCompliance: 1. Within 3 flights from the effective date of this Directive.\n\n    2. Within the time limits as detailed in the replacement criteria of Dassault Aviation S/B F50-A370.\n\n    3. Within 3 flights from the effective date of this Directive.\n\n    4. Within 3 flights from the effective date of this Directive.\n\nThis Airworthiness Directive becomes effective on 14 May 2003.","sortOrder":1}],"analysis":{"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":false,"description":"Scope matches the Service Bulletin and targets Falcon 50 serial numbers 2–329; the AD prescribes inspection, replacement as required by the Service Bulletin, and an AMM revision. It does not expand applicability beyond those aircraft or add additional types of corrective action beyond what the Service Bulletin and the listed AMM revision require (Applicability; Requirement items 1–4)."},"complexity_factors":["Tight compliance windows: inspections, fitting and AMM revision must be done within three flights of the AD effective date (Compliance items 1, 3, 4).","Dependence on external technical material: inspection method, measurement and replacement criteria are defined by Dassault Service Bulletin F50-A370 (Requirement items 1–3).","Variable compliance timing for replacements: timing for replacement is governed by the replacement criteria within the Service Bulletin, creating a range of deadlines rather than a single date (Compliance item 2).","Narrow applicability: applies only to Mystere Falcon 50 aeroplanes with serial numbers 2–329 inclusive (Applicability).","Administrative change: requires incorporation of temporary revision F50-WC-844.0/1 into the Airframe Maintenance Manual (Requirement item 4).","Cost and operational impact concentrated on operators/maintenance organisations who must perform inspections, possible part replacements and AMM update (Requirements 1–4).","Regulatory basis and enforcement: issued under the CASA delegate's power under CASR 1998 subregulation 39.1(1), indicating administrative issuance and enforcement by the regulator (preamble).","Cross-jurisdictional reference: notes DGAC Telex AD T2003-190(B), meaning procedures or findings from the French authority are incorporated by reference (Note)."],"plain_english_summary":"This Airworthiness Directive requires operators of Dassault Mystere Falcon 50 aeroplanes (serial numbers 2–329) to inspect and measure hydraulic lines, replace any chafed lines per Dassault Service Bulletin F50-A370, and add a temporary revision to the Airframe Maintenance Manual. Compliance deadlines are short (mostly within three flights) and replacement timing follows the Service Bulletin. It affects aircraft operators and maintenance organisations who bear inspection, parts and labour costs."},"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This is a standard, narrow safety directive addressing a specific mechanical defect in a specific aircraft type. The scope remains tightly focused on hydraulic line chafing in Falcon 50 aircraft as originally intended."},"complexity_factors":["Short, single-purpose directive with only 4 requirements","No defined terms section — relies on external manufacturer documents (Dassault Service Bulletin F50-A370)","Simple conditional structure: if aircraft in applicability range, then do requirements","External cross-references to manufacturer service bulletins and French aviation authority telex (DGAC), but these are standard for aircraft ADs","Clear, numbered compliance deadlines without nested exceptions","Total length: approximately 250 words of substantive text"],"plain_english_summary":"This AD requires owners, operators and maintenance organisations of Dassault Falcon 50s (S/N 2–329) to inspect and, if needed, replace or re-fit specific hydraulic lines per Dassault service instructions and to update maintenance manuals. The work must be done promptly (most inspections within three flights of the AD) to stop chafing that can cause hydraulic leaks and possible loss of hydraulic control."},"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"}},"importantCases":[],"_links":{"self":"/api/acts/ad-amd-50-31-hydraulic-line-chafing","history":"/api/acts/ad-amd-50-31-hydraulic-line-chafing/history","analysis":"/api/acts/ad-amd-50-31-hydraulic-line-chafing/analysis","conflicts":"/api/acts/ad-amd-50-31-hydraulic-line-chafing/conflicts","importantCases":"/api/acts/ad-amd-50-31-hydraulic-line-chafing/important-cases","documents":"/api/acts/ad-amd-50-31-hydraulic-line-chafing/documents"}}