{"id":"F2006B11050","name":"AD/L.40/9 Amdt 1 - Wing Structural Life Limitation","slug":"ad-l-40-9-amdt-1-wing-structural-life-limitation","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":56671,"registerId":"commonwealth-F2006B11050-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/L.40/9 Amdt 1 - Wing Structural 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)  Meta Sokol L.40 Series Aeroplanes\n\n \n\nAD/L.40/9\n\nAmdt 1\n\n\nWing Structural Life Limitation 2/73\n\n \n\nApplicability: All models with wing main spar lower caps exceeding 4000 hours time in service.\n\n \n\nRequirement: Retire from service the centre section and outer wing main spar lower caps, including the centre section to outer wing attachment fittings.\n\n \n\nCompliance: 31 March 1975.\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\n \n\n \n","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The instrument’s text sets a focused scope: it applies to all models with wing main spar lower caps exceeding 4,000 hours time in service and requires retirement of specified components by 31 March 1975 (Applicability; Requirement; Compliance). The text itself contains no indication that its scope was altered from its original statement."},"complexity_factors":["Narrow and clear applicability criterion: single numerical threshold (wing main spar lower caps > 4,000 hours time in service) (Applicability).","Single mandatory action: retirement of specified components (centre section and outer wing main spar lower caps and attachment fittings) (Requirement).","Fixed, single compliance date with no staged or conditional options (Compliance).","Absence of procedural detail on replacement parts, inspections, or permissible alternatives increases implementation ambiguity for maintainers (Requirement).","Potential technical ambiguity in the scope of “centre section to outer wing attachment fittings” that maintenance organisations must interpret (Requirement).","No enforcement, certification or administrative process described in the text, leaving execution and verification methods to the regulator or operators (no explicit section)."],"plain_english_summary":"This directive mandates retirement by 31 March 1975 of centre‑section and outer wing main spar lower caps (and attachment fittings) on Meta Sokol L.40 series aeroplanes once those parts exceed 4,000 hours TIS. It directly affects owners/operators and maintenance organisations, creating immediate removal and replacement costs, reduced available flying time until parts are restored, and leaves operators to decide how to restore airworthiness because no replacement or alternative procedures are specified."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, time-bound safety directive. It has not expanded beyond its original purpose of addressing a specific structural fatigue issue in a specific aircraft type. The amendment (Amdt 1) appears to be a routine update to the original AD/L.40/9, likely adjusting the compliance date or applicability, but does not represent scope creep."},"complexity_factors":["Extremely short document (under 200 words)","Only 4 operative elements: applicability, requirement, compliance date, and aircraft type","No defined terms section — technical terms ('spar lower caps', 'time in service') rely on standard aviation engineering definitions","No cross-references to other legislation or regulations","Single, unambiguous compliance obligation with hard deadline","No conditional logic, exceptions, or alternative compliance methods"],"plain_english_summary":"**What this is:** An Airworthiness Directive (AD) — essentially a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA).\n\n**What it does:** This directive forces owners and operators of **Meta Sokol L.40 series aeroplanes** to permanently ground specific parts of the aircraft once they hit a certain age. Specifically, if the wing's main structural supports (the \"lower caps\" of the main spar) have flown more than **4,000 hours**, those wing components must be **retired from service** by **31 March 1975**.\n\n**Who it affects:** Anyone flying or maintaining Meta Sokol L.40 aircraft in Australia — including private owners, flying schools, and charter operators.\n\n**Why it matters:** The wing spar is the backbone of the wing structure. If it fails, the wing can detach in flight. This AD was issued because metal fatigue in these components poses an unacceptable safety risk after 4,000 hours of use. Ignoring this directive means flying an aircraft that CASA has deemed potentially unairworthy — which is illegal and dangerous."}},"importantCases":[],"_links":{"self":"/api/acts/ad-l-40-9-amdt-1-wing-structural-life-limitation","history":"/api/acts/ad-l-40-9-amdt-1-wing-structural-life-limitation/history","analysis":"/api/acts/ad-l-40-9-amdt-1-wing-structural-life-limitation/analysis","conflicts":"/api/acts/ad-l-40-9-amdt-1-wing-structural-life-limitation/conflicts","importantCases":"/api/acts/ad-l-40-9-amdt-1-wing-structural-life-limitation/important-cases","documents":"/api/acts/ad-l-40-9-amdt-1-wing-structural-life-limitation/documents"}}