{"id":"F2006B04316","name":"AD/BEECH 99/6 - Wing Structural Fatigue Limitations","slug":"ad-beech-99-6-wing-structural-fatigue-limitations","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":44131,"registerId":"commonwealth-F2006B04316-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/BEECH 99/6 - Wing Structural Fatigue Limitations","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)  Beechcraft 99 Series Aeroplanes\n\n \n\nAD/BEECH 99/6 Wing Structural Fatigue Limitations 12/96\n\nApplicability: All model 99 aircraft.\n\n \n\nRequirement: Inspect and retire the wing structural components in accordance with the Beechcraft 99 Airliner Series Continued Airworthiness Program Inspection Manual P/N 98- 30131 Rev. A1, Sections 57-10 and 57-20.\n\n \n\nNote: FAA AD 92-15-13 refers.\n\n \n\nCompliance: This Directive takes effect 7 November 1996.\n\n \n\nBackground:  This Directive requires life limited components to be retired to prevent fatigue failure of the wing spar and associated 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","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The Directive's operative requirement—inspect and retire wing structural, life‑limited components per the specified Beechcraft manual (Requirement)—matches its stated purpose to prevent fatigue failure of the wing spar and associated structure (Background). The source text contains no material that indicates the Directive expands or narrows that stated purpose beyond the inspection/retirement obligation and the specified references."},"complexity_factors":["Clear, narrow applicability (all Model 99 aircraft) reduces scope ambiguity (Applicability).","Operative detail is delegated to an external document (Beechcraft Continued Airworthiness Program Inspection Manual P/N 98-30131 Rev. A1, Sections 57-10 and 57-20), creating a dependency on that manual for specifics (Requirement).","Requirement is procedural (inspect and retire), not performance‑based, so compliance actions are concrete but require recordkeeping and scheduling (Requirement; Compliance).","Reference to an external FAA AD adds a cross‑jurisdictional compliance consideration but does not add internal complexity (Note).","Effective date is fixed, creating a hard start for compliance and associated logistical planning (Compliance)."],"plain_english_summary":"The Directive requires all Beechcraft Model 99 aeroplanes to undergo inspections and retire life‑limited wing structural components per the Beechcraft 99 Continued Airworthiness Program Inspection Manual (Sections 57‑10/57‑20). It affects aircraft owners/operators, who must follow the manual’s intervals and bear inspection, replacement and downtime costs. Its purpose is to reduce wing spar fatigue‑failure risk; practical effects include changed maintenance planning, parts procurement and recordkeeping to ensure compliance."},"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 structural fatigue for one aircraft type. It has not expanded beyond its original purpose."},"complexity_factors":["Single, unambiguous applicability clause ('All model 99 aircraft')","Single cross-reference to an external technical manual (Beechcraft P/N 98-30131 Rev. A1)","No defined terms section — relies on standard aviation terminology","No conditional logic, exceptions, or nested provisions","Extremely short — approximately 150 words of substantive content","Clear compliance date with no alternative methods or phased implementation"],"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) for specific aircraft.\n\n**What it does:** It requires owners and operators of all Beechcraft Model 99 aircraft to inspect and eventually retire (permanently remove from service) certain wing structural components before they reach a specified number of flight hours or cycles. This is to prevent metal fatigue from causing catastrophic wing failure.\n\n**Who must follow it:** Anyone who owns, operates, or maintains a Beechcraft 99 series aircraft in Australia.\n\n**How to comply:** Operators must follow the inspection and retirement schedules set out in a specific Beechcraft manual (Part Number 98-30131, Revision A1), particularly Sections 57-10 and 57-20, which deal with wing structure.\n\n**Why it matters:** Metal fatigue is a silent killer in aviation — tiny cracks grow over time until a part fails suddenly. This directive prevents wing spar failure, which could cause the wing to break off in flight. The directive references a similar US Federal Aviation Administration (FAA) order (AD 92-15-13), showing this was a known safety issue internationally."}},"importantCases":[],"_links":{"self":"/api/acts/ad-beech-99-6-wing-structural-fatigue-limitations","history":"/api/acts/ad-beech-99-6-wing-structural-fatigue-limitations/history","analysis":"/api/acts/ad-beech-99-6-wing-structural-fatigue-limitations/analysis","conflicts":"/api/acts/ad-beech-99-6-wing-structural-fatigue-limitations/conflicts","importantCases":"/api/acts/ad-beech-99-6-wing-structural-fatigue-limitations/important-cases","documents":"/api/acts/ad-beech-99-6-wing-structural-fatigue-limitations/documents"}}