{"id":"F2006B09981","name":"AD/FU24/2 Amdt 1 - Structural Component - Corrosion - Inspection","slug":"ad-fu24-2-amdt-1-structural-component-corrosion-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":55285,"registerId":"commonwealth-F2006B09981-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/FU24/2 Amdt 1 - Structural Component - Corrosion - Inspection","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)  Airparts (NZ) Ltd. FU 24 Series Aeroplanes\n\n \n\nAD/FU24/2\n\nAmdt 1\n\n\nStructural Component - Corrosion - Inspection 7/68\n\n \n\nApplicability: All models.\n\n \n\nRequirement:  Inspect fuselage longerons, centre wing, main and rear spars, wing attachment fittings and other major structural components for signs of corrosion and effect any necessary repairs.\n\n \n\nNote: This inspection will involve dismantling the aircraft as it is not provided with sufficient inspection panels to complete inspection of the main structure.\n\n \n\nCompliance: At intervals not exceeding 3 years for aircraft engaged in agricultural operations. At intervals not exceeding 5 years for aircraft engaged in operations other than agricultural.\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":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a standard, narrow airworthiness directive focused specifically on corrosion inspection of structural components for one aircraft type. It has not expanded beyond its original safety purpose."},"complexity_factors":["Very short document (approximately 150 words of substantive content)","Only 2 defined applicability categories (agricultural vs non-agricultural operations)","Simple binary compliance structure (3-year vs 5-year intervals)","No cross-references to other legislation or regulations","Single requirement with straightforward inspection scope","No conditional logic, exceptions, or nested provisions","Note provides practical guidance rather than legal complexity"],"plain_english_summary":"This is an **Airworthiness Directive** — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA). It applies to all models of **Airspeed (NZ) Ltd FU-24 series aeroplanes** (agricultural aircraft commonly known as the Fletcher).\n\n**What it requires:**\n- **Inspection** of critical structural parts including:\n  - Fuselage longerons (the main longitudinal beams running along the body of the aircraft)\n  - Centre wing section\n  - Main and rear spars (the internal beams that support the wings)\n  - Wing attachment fittings (where wings connect to the fuselage)\n  - Other major structural components\n- **Purpose:** To detect **corrosion** (rust or deterioration of metal) that could weaken the aircraft structure\n- **Repairs:** Any corrosion found must be repaired\n\n**Important practical note:** This inspection requires **dismantling the aircraft** because these planes weren't built with enough inspection panels to see inside the main structure otherwise.\n\n**How often:**\n- **Every 3 years** for aircraft used in agricultural operations (crop dusting, spraying)\n- **Every 5 years** for aircraft used for other purposes\n\n**Why it matters:** Corrosion in structural components can lead to catastrophic failure. Agricultural aircraft operate in harsh conditions (chemicals, moisture, dust), accelerating corrosion. This directive ensures these aging aircraft remain safe to fly."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The instrument is labelled as an amendment (\"AD/FU24/2 Amdt 1\") but the supplied text does not include the prior version or identify how the scope has changed. Based solely on the text provided, the AD prescribes inspection and repair obligations (see \"Requirement\" and \"Compliance\") for all models; no explicit comparison to an earlier scope is present in the supplied material."},"complexity_factors":["Technical inspection requirement of multiple major structural components (fuselage longerons, centre wing, main and rear spars, wing attachment fittings)","Mandatory dismantling due to insufficient inspection panels (increases labour, time and procedural steps)","Differentiated compliance intervals depending on aircraft operation type (agricultural: 3 years; other: 5 years)","Vague operational phrase \"effect any necessary repairs\" leaves scope and timing of repairs to maintenance judgement","Applicability to \"All models\" broadens the population affected but does not specify model-specific variance"],"plain_english_summary":"This airworthiness directive (AD) requires regular corrosion inspections and repairs for Airparts (NZ) Ltd. FU 24 Series aeroplanes. It applies to all models covered by the AD (\"Applicability: All models\").\n\nWhat the instrument requires (mechanics):\n- Inspect structural parts for corrosion: fuselage longerons, centre wing, main and rear spars, wing attachment fittings and other major structural components (\"Requirement: Inspect fuselage longerons, centre wing, main and rear spars, wing attachment fittings and other major structural components for signs of corrosion and effect any necessary repairs\").\n- Carry out any repairs found to be necessary as a result of the inspection (same quote as above).\n- The inspection must be intrusive: it will involve dismantling the aircraft because there are not sufficient inspection panels to see the main structure (\"Note: This inspection will involve dismantling the aircraft as it is not provided with sufficient inspection panels to complete inspection of the main structure\").\n- Timing: inspections must be repeated at intervals not exceeding 3 years for aircraft used in agricultural operations and not exceeding 5 years for aircraft used in operations other than agricultural (\"Compliance: At intervals not exceeding 3 years for aircraft engaged in agricultural operations. At intervals not exceeding 5 years for aircraft engaged in operations other than agricultural\").\n\nWho this affects and who carries costs and decisions:\n- Aircraft owners and operators of FU 24 Series aeroplanes must arrange and pay for the inspections and any repairs (the AD prescribes the inspection and repair obligations; see \"Requirement\" and \"Compliance\" lines).\n- Maintenance personnel or approved maintenance organisations will determine how to perform the inspections and what repairs are \"necessary\" in practice (the AD requires operators to \"effect any necessary repairs\").\n- The directive is issued under the Commonwealth civil aviation framework and appears in the Civil Aviation Safety Authority schedule of airworthiness directives (header: \"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY SCHEDULE OF AIRWORTHINESS DIRECTIVES\").\n\nImplementation effects, incentives and trade-offs:\n- The need to dismantle the aeroplane increases labour time and aircraft downtime compared with non-intrusive inspections (\"Note\" quoted above). Those are recurring costs when inspections are performed every 3 or 5 years depending on use.\n- Operators in agricultural roles face a higher inspection frequency (maximum 3 years) than other operators (maximum 5 years), imposing a higher recurring inspection and repair cost on agricultural operators (\"Compliance\" quoted above).\n- The AD sets maximum intervals (inspections must not exceed the stated intervals); operators may choose to inspect more frequently but cannot go beyond those maxima (implicit from the phrasing of the compliance intervals).\n- The phrase \"effect any necessary repairs\" delegates judgement about the scope of repairs to the party doing the maintenance (\"Requirement\" quoted above). That produces operational discretion for maintenance providers and an implementation choice for operators about repair standards and timing.\n\nPractical risks and burdens to note:\n- The lack of inspection panels requires dismantling to inspect the main structure, increasing complexity, labour and potential scheduling impacts on operations (\"Note\" quoted above).\n- Repairs identified during inspection impose additional direct costs and additional grounding time.\n\nSource citations: statements above are taken directly from the AD text lines labelled \"Applicability\", \"Requirement\", \"Note\" and \"Compliance\" in the supplied instrument."}},"importantCases":[],"_links":{"self":"/api/acts/ad-fu24-2-amdt-1-structural-component-corrosion-inspection","history":"/api/acts/ad-fu24-2-amdt-1-structural-component-corrosion-inspection/history","analysis":"/api/acts/ad-fu24-2-amdt-1-structural-component-corrosion-inspection/analysis","conflicts":"/api/acts/ad-fu24-2-amdt-1-structural-component-corrosion-inspection/conflicts","importantCases":"/api/acts/ad-fu24-2-amdt-1-structural-component-corrosion-inspection/important-cases","documents":"/api/acts/ad-fu24-2-amdt-1-structural-component-corrosion-inspection/documents"}}