{"id":"F2006B10158","name":"AD/GAF-N22/12 Amdt 1 - Rudder Control System - Inspection and Modification","slug":"ad-gaf-n22-12-amdt-1-rudder-control-system-inspection-and-modification","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":55757,"registerId":"commonwealth-F2006B10158-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/GAF-N22/12 Amdt 1 - Rudder Control System - 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)  \nGAF N22 and N24 Series Aeroplanes\n\nAD/GAF-N22/12\n\nAmdt 1\n\n  \n\nRudder Control System \\- Inspection and Modification\n\n  \n4/77\n\nApplicability: All models N22 and N22B with S/Nos. as listed in SB No. N22.27.7.\n\nRequirement: 1. Inspect the mounting of the rudder pulley bracket at FUS. STA. 67.95 in accordance with GAF ALERT SB No. N22.27.6.\n\n2. Modify the mounting of the rudder pulley bracket at FUS. STA. 67.95 and affix towbar maximum deflection indication in accordance with GAF SB No. N22.27.7.\n\nNote 1: Flight restrictions referred to in Alert SB Telex N22.27.5 must be adhered to until compliance with para. 2 is completed.\n\nNote 2: Incorporation of MODIFICATION N137 is an acceptable means of compliance with para. 2.\n\nCompliance: 1. Within 50 hours time in service after 24 December 1976 and thereafter at intervals not exceeding 50 hours time in service until modified.\n\n2. Within 200 hours time in service after 1 April 1977.","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":true,"description":"This document is Amendment 1 to AD/GAF‑N22/12 and updates the Airworthiness Directive by prescribing inspection and modification requirements for the rudder pulley bracket and towbar deflection indicator, adding interim inspection intervals, a modification deadline, and references to specific GAF service documents (AD/GAF‑N22/12 Amdt 1)."},"complexity_factors":["Technical specificity: requires work on a precise component (rudder pulley bracket at FUS. STA. 67.95)","Applicability limited to listed serial numbers (SB No. N22.27.7), requiring cross-checking fleet records","Multiple compliance deadlines and interim inspection intervals (50 hours until modified; 200 hours for final modification)","Cross-references to an Alert SB, a Service Bulletin and an alternative MOD (N137) as acceptable means of compliance","Immediate operational constraint: flight restrictions apply until modification is completed (Alert SB Telex N22.27.5)","Administrative burden on operators and maintainers to schedule repetitive inspections, perform modifications, and maintain records"],"plain_english_summary":"This Airworthiness Directive requires operators of GAF N22 and N22B aeroplanes (serial numbers listed in GAF SB No. N22.27.7) to inspect the rudder pulley bracket at fuselage station 67.95 and to modify that mounting and fit a towbar maximum‑deflection indicator. It sets interim 50‑hour inspection intervals until modification, a final modification deadline, and requires adherence to specified GAF alert and service bulletins (MOD N137 is an accepted compliance option). The directive affects aircraft owners/operators and maintenance providers who must schedule, perform and record the work."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a narrow, targeted safety directive addressing a specific mechanical defect in a specific aircraft type. It has not expanded beyond its original purpose of ensuring rudder system integrity in GAF N22/N24 series aircraft."},"complexity_factors":["Very short document (approximately 200 words)","Only 2 operative requirements with clear compliance deadlines","Minimal defined terms (only standard aviation abbreviations like 'S/Nos.' for serial numbers and 'FUS. STA.' for fuselage station)","Simple conditional structure: inspect repeatedly until modified, then modification deadline","Cross-references limited to 3 external manufacturer documents (service bulletins) which are incorporated by reference but not reproduced","No nested exceptions or complex logical operators"],"plain_english_summary":"This is an **Airworthiness Directive** — essentially a mandatory safety order issued by Australia's aviation regulator (CASA) for specific aircraft.\n\n**What it does:**\nIt requires owners and operators of certain **GAF N22 and N22B aircraft** (Australian-made utility planes, often called \"Nomads\") to inspect and fix a problem with the **rudder control system** — specifically, how a pulley bracket is mounted inside the fuselage.\n\n**Who it affects:**\n- Owners and operators of GAF N22 and N22B aircraft with specific serial numbers listed in a manufacturer service bulletin (SB No. N22.27.7)\n- Maintenance engineers working on these aircraft\n\n**What must be done:**\n1. **Inspection:** Check the rudder pulley bracket mounting at a specific location in the fuselage (station 67.95) every 50 hours of flight time, starting from 24 December 1976, until the modification is done.\n\n2. **Modification:** Permanently fix the bracket mounting and install a visual indicator showing maximum towbar deflection — this must be completed within 200 hours of flight time after 1 April 1977.\n\n**Why it matters:**\nThis addresses a **safety-critical defect**. The rudder controls the aircraft's yaw (left-right movement). If the pulley bracket fails, the pilot could lose rudder control. The \"towbar deflection indicator\" suggests the problem may relate to ground handling — possibly damage from towing operations affecting the rudder system.\n\n**Flight restrictions apply:** Until the modification is complete, pilots must follow temporary flight limitations outlined in an earlier emergency alert (Alert SB Telex N22.27.5)."}},"importantCases":[],"_links":{"self":"/api/acts/ad-gaf-n22-12-amdt-1-rudder-control-system-inspection-and-modification","history":"/api/acts/ad-gaf-n22-12-amdt-1-rudder-control-system-inspection-and-modification/history","analysis":"/api/acts/ad-gaf-n22-12-amdt-1-rudder-control-system-inspection-and-modification/analysis","conflicts":"/api/acts/ad-gaf-n22-12-amdt-1-rudder-control-system-inspection-and-modification/conflicts","importantCases":"/api/acts/ad-gaf-n22-12-amdt-1-rudder-control-system-inspection-and-modification/important-cases","documents":"/api/acts/ad-gaf-n22-12-amdt-1-rudder-control-system-inspection-and-modification/documents"}}