{"id":"F2006B09977","name":"AD/FU24/14 - Hopper and Spray Tank Installation - Modification","slug":"ad-fu24-14-hopper-and-spray-tank-installation-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":55270,"registerId":"commonwealth-F2006B09977-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/FU24/14 - Hopper and Spray Tank Installation - 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/FU24/14 Hopper and Spray Tank Installation - Modification 6/68\n\nApplicability: All models manufactured prior to S/Nos. 120 not modified in accordance with James Aviation JA/FU24/M92 or Air Parts SB AP14.\n\n \n\nRequirement: Modify the hopper installation in a manner approved by the Secretary to withstand a 12g forward loading in an emergency alighting case.\n\n \n\nCompliance: Forthwith.\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":3,"scope_assessment":{"changed":true,"description":"Yes. The directive imposes a mandatory modification requirement on FU‑24 aircraft manufactured before S/N 120 unless they have already been modified in accordance with the two specified modification documents. Mechanically, that extends a regulatory obligation onto that defined subset of earlier production aircraft (Applicability; Requirement), and requires immediate action (Compliance)."},"complexity_factors":["Clear, narrow applicability (pre‑S/N 120 FU‑24s not already modified) requiring verification of serial number and modification history (Applicability).","Technical performance requirement (withstand 12g forward loading) rather than a prescriptive modification, requiring engineering assessment and approval (Requirement).","Regulatory discretion: modification must be in a manner approved by the Secretary, creating an approval step and potential variation in acceptable methods (Requirement).","Urgent timing: immediate compliance obligation (\"Forthwith\") increases scheduling and operational pressure (Compliance).","Cross‑references to two existing modification documents (James Aviation JA/FU24/M92 and Air Parts SB AP14) require access to and understanding of those documents to determine exclusion from scope (Applicability)."],"plain_english_summary":"## What this directive does\n\n- This airworthiness directive requires a physical change to the hopper and spray tank installation on certain Airparts (NZ) Ltd FU‑24 series aeroplanes. (Requirement)\n- The installation must be modified so it can resist a 12g forward load that could occur in an emergency alighting (landing) event. (Requirement)\n- The modification must be carried out in a manner approved by the Secretary. (Requirement)\n- Aircraft that fall under this directive are those manufactured before serial number 120 and that have not already been modified according to either James Aviation JA/FU24/M92 or Air Parts SB AP14. (Applicability)\n- The modification must be completed immediately — compliance is required \"forthwith.\" (Compliance)\n\n## Who this affects\n\n- Owners/operators of FU‑24 aircraft manufactured prior to S/N 120 that have not already had the specified modifications must ensure their hopper and spray tank installation is modified in the approved way. (Applicability; Requirement; Compliance)\n- The Secretary (Civil Aviation authority) is the approving authority for the manner of modification. (Requirement)\n\n## Why it matters (officially stated purpose and practical implications)\n\n- Officially, the change is to ensure the hopper installation can withstand a 12g forward loading in an emergency alighting case. That is the stated safety objective to be achieved by the modification. (Requirement)\n\nPractical implications and trade‑offs implied by the directive's mechanics:\n\n- Direct obligation and likely cost/responsibility: The directive places an immediate obligation on the operators of affected aircraft to have the hopper installation modified (Applicability; Compliance). Practically, that will require procurement of parts and labour or use of an approved maintenance provider to perform the modification.\n\n- Approval and discretion: The Secretary must approve the manner of the modification (Requirement). That creates a compliance checkpoint and gives the regulator discretion over which modification designs or procedures are acceptable.\n\n- Verification and record checks: Determining whether an aircraft is within scope requires checking manufacture serial number and whether it has already been modified in accordance with the two referenced modifications (Applicability). That creates a small administrative burden to verify compliance history.\n\n- Timing and operational impact: The requirement to comply \"forthwith\" (Compliance) shortens the window for operators to schedule the work, which can cause downtime for aircraft and may concentrate demand for approved modification services.\n\n- Technical specification: The directive specifies a performance target (withstanding 12g forward loading) rather than prescribing a single technical solution. This allows different modification designs if they achieve the stated loading requirement and receive approval. (Requirement)\n\n## Sections relied on\n- Applicability: identifies which aircraft are covered. (Applicability)\n- Requirement: states the modification outcome (12g forward load capacity) and that modification must be approved by the Secretary. (Requirement)\n- Compliance: sets the timing as \"forthwith.\" (Compliance)"},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, targeted safety directive focused on a specific airworthiness issue in a specific aircraft series. It has not expanded beyond its original purpose of mandating hopper structural modifications for crashworthiness."},"complexity_factors":["Extremely short document (under 200 words)","Only 4 operative sections: Applicability, Requirement, Compliance, and header metadata","Zero defined terms requiring interpretation","No cross-references to other legislation (only references to specific aircraft modification schemes)","Single, unambiguous action required (modify hopper to 12g standard)","Simple binary applicability test (serial number threshold + exclusion for already-modified aircraft)","No conditional logic, exceptions, or nested provisions"],"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 requires a specific safety modification to certain agricultural aircraft (crop dusters/sprayers) made by Airparts (NZ) Ltd, specifically the FU 24 series.\n\n**Who it affects:**\n- **Aircraft owners/operators** of FU 24 series planes with serial numbers below 120\n- **Only if** the plane hasn't already been modified under two specific earlier schemes (James Aviation JA/FU24/M92 or Air Parts Service Bulletin AP14)\n\n**The safety problem:** The hopper (the tank that holds chemicals/seeds for spraying) and spray tank installation needs strengthening. The current design might not survive a forced landing (\"emergency alighting\") where the plane hits the ground nose-first with forces up to 12 times gravity (12g forward loading).\n\n**What must be done:** The hopper installation must be modified using a method approved by the Secretary (of the Department responsible for aviation). The modification must ensure the tank structure can withstand that 12g forward impact.\n\n**When:** Immediately (\"Forthwith\"). This is urgent — no grace period.\n\n**Why it matters:** Agricultural aircraft operate low and slow, often over rough terrain. A forced landing is a real risk. If the hopper collapses forward in a crash, it could rupture, spill toxic chemicals, injure the pilot, or compromise the aircraft structure. This AD prevents that."}},"importantCases":[],"_links":{"self":"/api/acts/ad-fu24-14-hopper-and-spray-tank-installation-modification","history":"/api/acts/ad-fu24-14-hopper-and-spray-tank-installation-modification/history","analysis":"/api/acts/ad-fu24-14-hopper-and-spray-tank-installation-modification/analysis","conflicts":"/api/acts/ad-fu24-14-hopper-and-spray-tank-installation-modification/conflicts","importantCases":"/api/acts/ad-fu24-14-hopper-and-spray-tank-installation-modification/important-cases","documents":"/api/acts/ad-fu24-14-hopper-and-spray-tank-installation-modification/documents"}}