{"id":"F2006B09982","name":"AD/FU24/31 Amdt 1 - Elevator Hinge and Attachment Fittings","slug":"ad-fu24-31-amdt-1-elevator-hinge-and-attachment-fittings","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":55289,"registerId":"commonwealth-F2006B09982-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/FU24/31 Amdt 1 - Elevator Hinge and Attachment Fittings","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/FU24/31\n\nAmdt 1\n\n  \nElevator Hinge and Attachment Fittings 8/95\n\nApplicability: All models with elevator hinge fitting part number 242220 and/or elevator attachment fitting part number 243008 installed.\n\nRequirement: 1. Examine the elevator attachment fittings for cracking and corrosion, paying particular attention to the rivet holes in the transverse flange.\n\n2. Examine the elevator hinge fittings for cracking and corrosion, particularly in the vicinity of the hinge bolt holes.\n\nNote: To prevent the start of intercrystalline corrosion and subsequent failure due to stress corrosion, attention is drawn to the necessity for preserving the original protective treatment on all such parts, particularly when used in the corrosive environment associated with agricultural aircraft.\n\nCompliance: At intervals not to exceed 500 hours time in service.\n\nThe Compliance of the initial issue of this Directive remains unchanged. This Amendment is effective from 20 July 1995.\n\nBackground: In-service experience of cracking prompted the need for this inspection.\n\nAmendment 1 is issued to restrict applicability to aircraft with aluminium fittings installed.","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This amendment slightly narrows the original directive's scope by restricting applicability to aircraft with aluminium fittings installed, rather than all aircraft with these part numbers. This is a minor technical refinement rather than scope creep."},"complexity_factors":["Single, specific aircraft type and two discrete part numbers","Two straightforward inspection requirements with clear focus areas","Single compliance interval (500 hours) with no conditional exceptions","Minimal cross-referencing (only references original directive for compliance continuity)","Short document (approximately 200 words) with no defined terms section","Narrow amendment scope (merely restricts applicability to aluminium fittings)"],"plain_english_summary":"This CASA Airworthiness Directive mandates operators of Airparts (NZ) Ltd FU 24 series aeroplanes fitted with aluminium elevator hinge (242220) and attachment (243008) fittings to inspect those tail components every 500 flight hours for cracks, rivet/bolt‑hole corrosion, intercrystalline and stress corrosion.  \n\nIt matters because cracking or corrosion of these fittings can cause loss of pitch control; inspections were prompted by in‑service failures and Amendment 1 narrows the affected fleet."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"Amendment 1 narrows the directive's scope by limiting applicability to aircraft with the specified aluminium elevator fittings installed. The original directive covered installations of the listed part numbers generally; the amendment excludes non‑aluminium installations. Compliance requirements and the 500‑hour inspection interval otherwise remain unchanged (effective 20 July 1995)."},"complexity_factors":["Technical specificity: identifies two exact part numbers (242220, 243008) which narrows scope and requires part-tracking.","Material-based applicability: Amendment 1 restricts the directive to aluminium fittings only, creating a material-dependent compliance decision.","Inspection prescription: mandates visual/physical inspection focus areas (rivet holes, hinge-bolt holes) and a fixed interval (≤500 hours), requiring maintenance scheduling.","Preservation obligation: note advising retention of original protective treatment imposes ongoing corrosion-control practice.","Regulatory interaction: states that compliance with the initial issue remains unchanged while amendment alters applicability, creating a potential records/interpretation burden for operators.","Operational impact concentration: agricultural operators face higher corrosion risk per the note, which may increase inspection and maintenance costs for a concentrated group of operators."],"plain_english_summary":"This airworthiness directive requires inspections of specific elevator hinge (PN 242220) and attachment (PN 243008) fittings for cracking and corrosion, paying particular attention to rivet and hinge-bolt holes, at intervals not exceeding 500 hours. It also advises preserving the original protective treatment on those parts.\n\nIt applies to Airparts (NZ) FU 24 series aeroplanes fitted with the listed aluminium fittings and matters because in‑service cracking prompted the inspections; Amendment 1 narrows applicability to aluminium fittings (effective 20 July 1995)."}},"importantCases":[],"_links":{"self":"/api/acts/ad-fu24-31-amdt-1-elevator-hinge-and-attachment-fittings","history":"/api/acts/ad-fu24-31-amdt-1-elevator-hinge-and-attachment-fittings/history","analysis":"/api/acts/ad-fu24-31-amdt-1-elevator-hinge-and-attachment-fittings/analysis","conflicts":"/api/acts/ad-fu24-31-amdt-1-elevator-hinge-and-attachment-fittings/conflicts","importantCases":"/api/acts/ad-fu24-31-amdt-1-elevator-hinge-and-attachment-fittings/important-cases","documents":"/api/acts/ad-fu24-31-amdt-1-elevator-hinge-and-attachment-fittings/documents"}}