{"id":"F2006B11325","name":"AD/MSR/26 - Wing Structural Fatigue Life Limitation","slug":"ad-msr-26-wing-structural-fatigue-life-limitation","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":57182,"registerId":"commonwealth-F2006B11325-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/MSR/26 - Wing Structural Fatigue Life Limitation","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)  Aerospatiale Rallye Series Aeroplanes\n\n \n\nAD/MSR/26 Wing Structural Fatigue Life Limitation 3/80\n\nApplicability: All series 235E aircraft.\n\n \n\nRequirement: Retire the wing main spar and the centre section splice plates from service.\n\n \n\nNote: This fatigue life limitation will be reviewed upon receipt of future substantiation data from the manufacturer.\n\n \n\nCompliance: Upon or prior to achieving 2800 hours component time in service.\n\n \n\nBackground: Based on information provided by the manufacturer, a safe fatigue life has been determined for the wing structure.\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":2,"scope_assessment":{"changed":false,"description":"The instrument sets an initial, specific fatigue-life limitation (retirement of wing main spar and centre section splice plates at or before 2,800 hours) and does not itself indicate any prior wider or narrower scope. It does provide for a future review if the manufacturer supplies further substantiation data (\"Note\"), but the text contains no indication that the scope has already been changed from an earlier intent."},"complexity_factors":["Narrow applicability: affects a single aircraft type (All series 235E) (Applicability).","Single, discrete required action: retirement of two named components (Requirement).","Clear numeric compliance threshold: 2,800 hours component time in service (Compliance).","Lack of procedural detail: does not specify replacement procedures, disposal, certification or record-keeping formats (Requirement; Compliance).","Built-in conditional review: future change possible upon manufacturer's substantiation data, introducing some regulatory uncertainty (Note)."],"plain_english_summary":"This instrument mandates permanent retirement of the wing main spar and centre‑section splice plates on all Aerospatiale Rallye series 235E aircraft when either component reaches 2,800 hours component time-in-service. It affects owners/operators (who bear removal, disposal and replacement costs) and is based on manufacturer data establishing a safe fatigue life, with the limit subject to future review if further substantiation is provided."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, single-issue safety directive focused specifically on wing fatigue limits for one aircraft series. It has not expanded beyond its original purpose; Airworthiness Directives by design are narrow, targeted instruments addressing specific safety concerns as they emerge."},"complexity_factors":["Extremely short document — approximately 150 words of substantive content","Only 2 defined applicability criteria (aircraft series and component time)","Single, unambiguous compliance requirement with clear numerical threshold (2800 hours)","No cross-references to other legislation or regulations beyond the parent Civil Aviation Regulations 1998 citation","No conditional logic, exceptions, or nested provisions","Plain language requirement ('Retire...from service') with minimal aviation jargon"],"plain_english_summary":"This is an **Airworthiness Directive** — essentially a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA). It applies to a specific type of light aircraft: the **Aerospatiale Rallye 235E series**.\n\n**What it does:**\nThe directive orders owners and operators to **permanently remove and replace critical wing components** — specifically the main wing spar (the central structural beam that holds the wing together) and the centre section splice plates (metal plates that join sections of the wing) — once these parts have accumulated **2,800 hours of flight time**.\n\n**Why it matters:**\nMetal parts on aircraft suffer from **fatigue** — tiny cracks that develop over thousands of flight cycles due to repeated stress from takeoffs, landings, and turbulence. Without this directive, these wing components could fail catastrophically in flight. The 2,800-hour limit represents the \"safe life\" calculated by the manufacturer — the point beyond which the risk of structural failure becomes unacceptable.\n\n**Who it affects:**\n- Owners and operators of Aerospatiale Rallye 235E aircraft\n- Maintenance organisations servicing these planes\n- Pilots flying them\n\n**Key point:** This isn't optional. \"Compliance\" means you must do this before or exactly at 2,800 hours — not after. The note indicates CASA may adjust this limit if the manufacturer provides new engineering data proving the parts can safely last longer."}},"importantCases":[],"_links":{"self":"/api/acts/ad-msr-26-wing-structural-fatigue-life-limitation","history":"/api/acts/ad-msr-26-wing-structural-fatigue-life-limitation/history","analysis":"/api/acts/ad-msr-26-wing-structural-fatigue-life-limitation/analysis","conflicts":"/api/acts/ad-msr-26-wing-structural-fatigue-life-limitation/conflicts","importantCases":"/api/acts/ad-msr-26-wing-structural-fatigue-life-limitation/important-cases","documents":"/api/acts/ad-msr-26-wing-structural-fatigue-life-limitation/documents"}}