{"id":"F2006B09992","name":"AD/FU24/45 - Fuel Quantity Indication - Modification","slug":"ad-fu24-45-fuel-quantity-indication-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":55332,"registerId":"commonwealth-F2006B09992-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/FU24/45 - Fuel Quantity Indication - Modification","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/FU24/45 Fuel Quantity Indication - Modification 4/72\n\nApplicability: All models with mechanical type fuel quantity indicators fitted to inboard end of left hand fuel tank system.\n\n \n\nRequirement: Modify the fuel quantity indicating system by:\n\n \n\n1. Fitting electrical indicators; or\n\n\n \n\n2.    Repositioning the left hand indicator assembly to a scheme approved by the Secretary.\n\n \n\nNote: Airparts (NZ) Ltd. drawing 246158 is an acceptable means of compliance with\n\n1. (above).\n\n \n\nCompliance: Before 30 September 1973.\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 discrete, single-issue safety directive targeting a specific mechanical defect in a specific aircraft type. It has not expanded beyond its original purpose of mandating fuel gauge modifications."},"complexity_factors":["Very short document (under 200 words)","Only 2 substantive requirements with clear 'either/or' structure","Single defined applicability criterion (mechanical indicators on left-hand tank)","One cross-reference to a specific engineering drawing (246158)","No nested exceptions, conditional clauses, or interpretive provisions","Plain language throughout with minimal aviation jargon"],"plain_english_summary":"This is an **Airworthiness Directive** — a mandatory safety order issued by Australia's aviation safety regulator (CASA) requiring owners of specific aircraft to fix a known safety problem.\n\n**What it does:**\nOrders modifications to the fuel gauge system on certain **Airparts (NZ) Ltd FU 24 series aeroplanes** (agricultural aircraft). The problem involves mechanical fuel quantity indicators mounted at the inboard end of the left-hand fuel tank.\n\n**Who it affects:**\nOwners and operators of all FU 24 models fitted with these specific mechanical fuel indicators.\n\n**What must be done:**\nOperators must choose **one** of two fixes:\n- **Option 1:** Replace the mechanical indicators with electrical ones (using Airparts drawing 246158 as an approved method); or\n- **Option 2:** Move the left-hand indicator assembly to a new position, but only if that new position is approved by the Secretary (the government official responsible for aviation safety at the time).\n\n**Why it matters:**\nFuel quantity indication failures can lead to fuel starvation, engine failure, and crashes. This directive forces a fix before a deadline to prevent accidents.\n\n**Compliance deadline:**\nBefore 30 September 1973 (now long past — this is a historical directive)."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The directive sets a specific, limited requirement for modification of the fuel quantity indication on identified aircraft. The text does not show any change to that scope; it prescribes two alternative technical solutions, names an accepted drawing for one option, and sets a compliance date (Applicability; Requirement; Note; Compliance)."},"complexity_factors":["Narrow applicability limited to FU 24 models with mechanical indicators fitted at the inboard end of the left-hand fuel tank (Applicability)","Two alternative compliance routes reduce procedural complexity (Requirement 1–2)","One explicitly accepted means of compliance for the electrical option (Airparts drawing 246158) lowers design/approval uncertainty (Note)","A single fixed compliance deadline creates a simple schedule but no phased requirements (Compliance)","Regulatory discretion required for approval of repositioning schemes adds a modest procedural step (Requirement 2)"],"plain_english_summary":"This AD requires owners/operators of Airparts FU 24 aeroplanes with a mechanical fuel‑quantity indicator at the inboard left tank to modify the system by 30 September 1973: either fit electrical indicators (Airparts drawing 246158 is an acceptable means) or reposition the left‑hand indicator to a layout approved by the Secretary. Compliance costs and approval steps fall to the operator, and the Secretary has discretion over repositioning schemes."}},"importantCases":[],"_links":{"self":"/api/acts/ad-fu24-45-fuel-quantity-indication-modification","history":"/api/acts/ad-fu24-45-fuel-quantity-indication-modification/history","analysis":"/api/acts/ad-fu24-45-fuel-quantity-indication-modification/analysis","conflicts":"/api/acts/ad-fu24-45-fuel-quantity-indication-modification/conflicts","importantCases":"/api/acts/ad-fu24-45-fuel-quantity-indication-modification/important-cases","documents":"/api/acts/ad-fu24-45-fuel-quantity-indication-modification/documents"}}