{"id":"F2006B10003","name":"AD/FU24/56 - Engine Controls - Inspection and Modification","slug":"ad-fu24-56-engine-controls-inspection-and-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":55361,"registerId":"commonwealth-F2006B10003-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/FU24/56 - Engine Controls - Inspection and Modification","content":"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n![](image.001.png)  \nAirparts (NZ) Ltd. FU 24 Series Aeroplanes\n\nAD/FU24/56 Engine Controls \\- Inspection and Modification 5/80\n\nApplicability: Models FU24-954 and FU24A-954 with S/Nos. 258 to 274 except 262, 269 and 270.\n\nAlso, any model FU24-950. \\-950M or FU24A-950, \\-950M with engine cowls modified as per NZ AIL Mod. A1/FU/0081.\n\nRequirement: 1. Inspect ball and socket joints P/N 242997 at engine end of the throttle and mixture controls for wear or damage and check for smooth operation of controls over full range of travel.\n\n2. Modify per Aerospace SB ASB/FU/069.\n\nCompliance: Para. 1 \\- Within 10 hours time in service after 10 April, 1980 and thereafter at intervals not exceeding 50 hours time in service until modified.\n\nPara. 2 \\- Within 100 hours time in service.\n\nBackground: Excessive wear has been found on engine control ball joints due to angular alignment at extremes of travel.","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The directive, as presented, sets out explicit applicability, inspection and modification requirements, and compliance intervals. There is no language in the text indicating an expansion or narrowing of scope from an earlier instrument; the scope is confined to the listed models, serial numbers and the cowl-modified variants as stated (Applicability; Requirement; Compliance)."},"complexity_factors":["Narrow and specific applicability by model and serial number, with three serial numbers explicitly excluded (Applicability).","Two-step requirement: recurring inspections of a specific part (P/N 242997) plus a mandatory modification per an external service bulletin (Requirement).","Staged compliance schedule with a short initial inspection window (10 hours) and repeated intervals (50 hours) until modification, and a separate 100-hour deadline for the modification (Compliance).","References to external technical documents (Aerospace SB ASB/FU/069 and NZ AIL Mod. A1/FU/0081) that contain the detailed modification and cowl-change criteria (Requirement; Applicability).","Technical subject matter (engine control ball joints, angular alignment at extremes of travel) requires maintenance/engineering capability to assess and implement (Requirement; Background)."],"plain_english_summary":"This directive mandates inspection of engine-end ball-and-socket joints on throttle and mixture controls for specified Airparts FU24-series aeroplanes, requiring checks for wear and smooth full travel and a modification per Aerospace Service Bulletin ASB/FU/069. Owners/operators must inspect within 10 hours TIS after 10 Apr 1980, repeat every 50 hours until the mod is done, and complete the modification within 100 hours. Costs fall to the operators; the actions address discovered wear that can affect control reliability."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, targeted safety directive addressing a specific mechanical defect in a limited fleet of agricultural aircraft. It has not expanded beyond its original purpose of mandating inspection and modification of engine control joints."},"complexity_factors":["Single, specific aircraft type and limited serial number range","Only 2 substantive requirements (inspection and modification)","Clear compliance deadlines with simple time-in-service calculations","No defined terms section or complex cross-referencing","Background explanation provided in plain language","Total length is approximately 150 words"],"plain_english_summary":"This is an **Airworthiness Directive** — a mandatory safety order issued by Australia's Civil Aviation Safety Authority (CASA) for specific aircraft.\n\n**What it does:**\nOrders owners and operators of certain **Airparts FU24 series agricultural aeroplanes** to:\n- **Inspect** the throttle and mixture control joints for wear or damage, and check they move smoothly through their full range\n- **Modify** the engine controls according to a specific manufacturer's service bulletin\n\n**Who it affects:**\n- Owners of FU24-954 and FU24A-954 models with serial numbers 258–274 (excluding 262, 269, and 270)\n- Owners of FU24-950, FU24-950M, FU24A-950, or FU24A-950M models that have had a specific engine cowl modification (NZ AIL Mod. A1/FU/0081)\n\n**Why it matters:**\nWorn or misaligned engine control joints could cause the throttle or mixture controls to fail or stick — a serious safety risk during flight. The directive requires regular inspections until a permanent fix is installed.\n\n**Deadlines:**\n- **Inspections:** Must start within 10 flight hours after 10 April 1980, then repeat every 50 flight hours until the modification is done\n- **Modification:** Must be completed within 100 flight hours"}},"importantCases":[],"_links":{"self":"/api/acts/ad-fu24-56-engine-controls-inspection-and-modification","history":"/api/acts/ad-fu24-56-engine-controls-inspection-and-modification/history","analysis":"/api/acts/ad-fu24-56-engine-controls-inspection-and-modification/analysis","conflicts":"/api/acts/ad-fu24-56-engine-controls-inspection-and-modification/conflicts","importantCases":"/api/acts/ad-fu24-56-engine-controls-inspection-and-modification/important-cases","documents":"/api/acts/ad-fu24-56-engine-controls-inspection-and-modification/documents"}}