{"id":"F2006B02818","name":"AD/B737/116 Amdt 1 - Yaw Damper and Rudder Power Control Unit Wiring Change","slug":"ad-b737-116-amdt-1-yaw-damper-and-rudder-power-control-unit-wiring-change","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":42160,"registerId":"commonwealth-F2006B02818-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/B737/116 Amdt 1 - Yaw Damper and Rudder Power Control Unit Wiring Change","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)  \nBoeing 737 Series Aeroplanes\n\nAD/B737/116\n\nAmdt 1\n\n  \n\nYaw Damper and Rudder Power Control Unit Wiring Change\n\n  \n6/99\n\nApplicability: All Boeing 737 \\-300, \\-400 and \\-500 model aircraft up to and including line position 2907.\n\nRequirement: 1\\. Install new wiring and associated hardware for a new yaw damper and pressure reducer bypass valve in accordance with Boeing Service Bulletin (SB) 737-22- 1124 Revision 1 dated 25 March 1999.\n\nNote: FAA AD 97-14-03 Amdt 39-10060 refers.\n\nCompliance: 1. The original compliance of ‘No later than 26 March 2002’ remains unchanged.\n\nThis Amendment becomes effective on 17 June 1999.\n\nBackground: The FAA issued AD 97-14-03 to prevent both excessive rudder authority resulting in reduced controllability of the aircraft as well as malfunctions of the yaw damper system which could cause sudden uncommanded yawing of the aircraft and consequent injury to passengers and crewmembers. Boeing responded with the issue of SB 737-22-1124, detailing the installation of new wiring for the proposed hardware changes which will be the subject of another AD.\n\nThis amendment limits the applicability and introduces revised wiring requirements.\n\nThe original issue of this Airworthiness Directive became effective on 26 March 1998.","sortOrder":0}],"analysis":{"flash_summary_failed":{"failed":true,"reason":"A positive credit balance is required for all requests, including BYOK, so fallback providers remain available. Add credits at https://vercel.com/d?to=%2F%5Bteam%5D%2F%7E%2Fai%3Fmodal%3Dtop-up to continue.","source":"analysis-cron"},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"The amendment narrows and clarifies scope: it limits applicability to 737-300/-400/-500 aircraft up to line position 2907 and introduces revised wiring requirements implemented via Boeing SB 737-22-1124 Rev 1, while leaving the original compliance date unchanged. (Source: 'Applicability' and 'This amendment limits the applicability and introduces revised wiring requirements.')"},"complexity_factors":["Technical subject-matter: aircraft yaw damper and rudder power control unit wiring changes require specialised maintenance expertise and parts.","Limited applicability: applies only to Boeing 737-300, -400 and -500 up to line position 2907 (increases clarity but requires line-number verification).","Reliance on external document: prescribes compliance by following Boeing Service Bulletin 737-22-1124 Revision 1 (operator must obtain and follow SB).","Compliance timing: retains an existing deadline (no later than 26 March 2002), creating scheduling pressure for operators.","Operational impact: installation will create aircraft downtime and procurement/installation burdens for operators.","Regulatory linkage: references an earlier FAA AD (97-14-03), so technical and compliance risk is tied to prior foreign regulator findings."],"plain_english_summary":"This amendment requires owners/operators of Boeing 737-300, -400 and -500 aeroplanes (up to line position 2907) to install new wiring and associated hardware for a revised yaw damper and rudder power control unit under Boeing Service Bulletin 737-22-1124 Revision 1. The original compliance date remains no later than 26 March 2002. The rule is intended to reduce excessive rudder authority and yaw-damper malfunctions; it therefore imposes parts, installation work and downtime costs on aircraft operators and relies on the manufacturer’s service bulletin for technical steps."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This amendment slightly narrows the applicability (limiting to line position 2907 and below) and updates wiring requirements, but remains tightly focused on the original safety purpose — preventing rudder and yaw damper malfunctions. No scope creep detected."},"complexity_factors":["Very short document (under 300 words)","Only 1 defined term implicitly used (line position — a manufacturing serial reference)","Single primary requirement with one compliance deadline","No nested exceptions or conditional logic","Clear cross-reference to only one external document (FAA AD 97-14-03) and one Boeing Service Bulletin","Straightforward applicability clause limiting to specific aircraft models and production line numbers"],"plain_english_summary":"This CASA Airworthiness Directive mandates installation of revised wiring and hardware for the yaw damper and rudder power control unit on certain Boeing 737-300/-400/-500 aircraft to prevent excessive rudder travel and yaw-damper failures that could cause loss of control or injuries. Amendment 1 tightens which aircraft are affected and updates wiring requirements; operators must comply by 26 March 2002 or the aircraft cannot legally fly."}},"importantCases":[],"_links":{"self":"/api/acts/ad-b737-116-amdt-1-yaw-damper-and-rudder-power-control-unit-wiring-change","history":"/api/acts/ad-b737-116-amdt-1-yaw-damper-and-rudder-power-control-unit-wiring-change/history","analysis":"/api/acts/ad-b737-116-amdt-1-yaw-damper-and-rudder-power-control-unit-wiring-change/analysis","conflicts":"/api/acts/ad-b737-116-amdt-1-yaw-damper-and-rudder-power-control-unit-wiring-change/conflicts","importantCases":"/api/acts/ad-b737-116-amdt-1-yaw-damper-and-rudder-power-control-unit-wiring-change/important-cases","documents":"/api/acts/ad-b737-116-amdt-1-yaw-damper-and-rudder-power-control-unit-wiring-change/documents"}}