{"id":"F2006B03191","name":"AD/B747/299 - Yaw Damper Actuator","slug":"ad-b747-299-yaw-damper-actuator","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"repealed","isInForce":false,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":42563,"registerId":"commonwealth-F2006B03191-current","compilationNumber":null,"startDate":"2026-04-01","status":"Repealed","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"AIRWORTHINESS DIRECTIVE","sectionType":"part","heading":"AIRWORTHINESS DIRECTIVE","content":"# AIRWORTHINESS DIRECTIVE\n\n![](image.001.png)  \n\nFor the reasons set out in the background section, the CASA delegate whose signature appears below issues the following Airworthiness Directive (AD) under subregulation 39.1 (1) of CASR 1998. The AD requires that the action set out in the requirement section (being action that the delegate considers necessary to correct the unsafe condition) be taken in relation to the aircraft or aeronautical product mentioned in the applicability section: (a) in the circumstances mentioned in the requirement section; and (b) in accordance with the instructions set out in the requirement section; and (c) at the time mentioned in the compliance section.\n\n![](image.001.png)  \n\nBoeing 747 Series Aeroplanes","sortOrder":0},{"sectionNumber":"AD/B747/299 Yaw Damper Actuator 1/2004","sectionType":"part","heading":"AD/B747/299 Yaw Damper Actuator 1/2004","content":"# AD/B747/299 Yaw Damper Actuator 1/2004\n\nApplicability: Model 747-400, \\-400D, and \\-400F series aircraft, as listed in Boeing Alert Service Bulletin 747-27A2397, dated 24 July 2003.\n\nRequirement: Action in accordance with the technical requirements of FAA AD 2003-23-01 Amdt 39-13364.\n\nCompliance: As specified in the Requirement document, with a revised effective date of 22 January 2004.\n\nThis Airworthiness Directive becomes effective on 22 January 2004.\n\nBackground: This Directive requires an ultrasonic inspection of the yaw damper portion of the upper and lower rudder power control modules main manifold for cracking. Such cracking, unless detected and corrected, could result in an uncommanded left rudder hardover, consequent increased pilot workload, and possible runway departure upon landing.\n\n![Signature of David Villiers, Delegate of the Civil Aviation Safety Authority.](image.002.png)  \n\nDavid Villiers\n\nDelegate of the Civil Aviation Safety Authority 5 December 2003\n\n![](image.001.png)","sortOrder":1}],"analysis":{"kimi_summary":{"_metrics":{"model":"kimi-k2.5","source":"moonshot-batch","completionTokens":1458},"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This appears to be the original issuance of the directive. The scope remains tightly focused on the specific unsafe condition (cracking in yaw damper actuators) affecting the identified Boeing 747 models, without expansion into unrelated systems or aircraft types."},"complexity_factors":["Incorporation by reference of FAA AD 2003-23-01, requiring operators to consult foreign regulatory material","Technical aviation terminology requiring specialised knowledge (yaw damper, rudder hardover, power control modules)","Cross-reference to Boeing Alert Service Bulletin 747-27A2397 to determine exact aircraft applicability"],"plain_english_summary":"This is a safety order for airlines operating specific Boeing 747 models (the 747-400, 747-400D, and 747-400F). It requires an **ultrasonic inspection** (using high-frequency sound waves to detect internal cracks) of the \"yaw damper\" components in the upper and lower rudder power control modules.\n\n**What the problem is:** Cracks in these parts could cause an \"uncommanded left rudder hardover\"—meaning the rudder could suddenly swing hard to the left without the pilot touching the controls. This could make the aircraft harder to control during landing and potentially cause it to run off the runway.\n\n**What must be done:** Airlines must inspect these components following the technical instructions in an American aviation safety order (FAA AD 2003-23-01). The directive became effective on **22 January 2004**.\n\n**Who is affected:** Operators of Boeing 747-400 series aircraft listed in Boeing Alert Service Bulletin 747-27A2397."}},"importantCases":[],"_links":{"self":"/api/acts/ad-b747-299-yaw-damper-actuator","history":"/api/acts/ad-b747-299-yaw-damper-actuator/history","analysis":"/api/acts/ad-b747-299-yaw-damper-actuator/analysis","conflicts":"/api/acts/ad-b747-299-yaw-damper-actuator/conflicts","importantCases":"/api/acts/ad-b747-299-yaw-damper-actuator/important-cases","documents":"/api/acts/ad-b747-299-yaw-damper-actuator/documents"}}