{"id":"F2006B03364","name":"AD/B767/189 - Aileron Control Override Quadrant - Replacement","slug":"ad-b767-189-aileron-control-override-quadrant-replacement","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":42814,"registerId":"commonwealth-F2006B03364-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/B767/189 - Aileron Control Override Quadrant - Replacement","content":"COMMONWEALTH OF AUSTRALIA (Civil Aviation Safety Regulations 1998), PART 39 \\- 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n![](image.001.png)  \n\nAIRWORTHINESS 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 767 Series Aeroplanes\n\nAD/B767/189 Aileron Control Override Quadrant \\-\n\nReplacement\n\n  \n10/2003\n\nApplicability: Model B767 \\-200, \\-300 and \\-300F series aeroplanes with line numbers 1 to 836 inclusive.\n\nRequirement: 1. Replace aileron control override quadrant with modified unit in accordance with Boeing Alert Service Bulletin 767-27A0175 dated 25 October 2001.\n\n2. Unless modified in accordance with the requirements of this Directive, no aileron control override quadrant may be installed on any aircraft.\n\nNote 1: This Directive does not require accomplishment of the actions specified in Boeing Service Bulletin 767-27-0142.\n\nNote 2: FAA AD 2003-15-03 Amdt 39-13245 refers.\n\nCompliance: For Requirement 1: Within 17 months after the effective date of this Directive.\n\nFor Requirement 2: From the effective date of this Directive.\n\nThis Airworthiness Directive becomes effective on 2 October 2003.\n\nBackground: The existing steel ball bearings in the aileron override quadrant mechanism are subject to corrosion. In the event of other than normal conditions occurring in the primary aileron control path corroded steel balls bearings in the override quadrant may disable the secondary control path that could lead to a subsequent reduction in lateral controllability of the aeroplane. This Directive therefore requires the replacement of the aileron control quadrant with a modified assembly containing Corrosion Resistant Steel (CRES) ball bearings.\n\n![Signature of James Coyne, Delegate of the Civil Aviation Safety Authority.](image.002.png)  \n\nJim Coyne\n\n![](image.001.png)Delegate of the Civil Aviation Safety Authority 20 August 2003\n\nThe above AD is notified in the Commonwealth of Australia Gazette on 10 September 2003.\n\n  \n\nPage 1 of 1","sortOrder":0}],"analysis":{"flash_summary":{"complexity_score":2,"scope_assessment":{"changed":false,"description":"The AD sticks to a narrow safety purpose: replace a specific component to reduce corrosion-related failure risk in the aileron override mechanism. It does not broaden the obligations beyond that single technical fix, nor add unrelated requirements. Therefore it has not grown beyond its original safety-focused intent."},"complexity_factors":["Short, single‑component directive: one primary mandated action (replace quadrant) and one prohibition (no installation of unmodified part)","Single compliance timeframe: replace within 17 months","Limited applicability: specific aircraft models and line numbers 1–836","Two external document references: Boeing Alert Service Bulletin 767-27A0175 and FAA AD 2003-15-03","One explicit negative carve‑out (does not require Boeing Service Bulletin 767-27-0142)","Minimal conditional logic or nested exceptions"],"plain_english_summary":"**What this directive does (mechanically):**\n\n- Applies to Boeing 767-200, -300 and -300F aeroplanes with line numbers 1–836 inclusive (Applicability).\n- Requires operators to remove and replace the existing aileron control override quadrant with a modified unit that uses corrosion-resistant steel (CRES) ball bearings, following Boeing Alert Service Bulletin 767-27A0175 dated 25 October 2001 (Requirement 1).\n- Prohibits installing an unmodified aileron control override quadrant on any affected aircraft from the effective date of the AD (Requirement 2).\n- Sets the deadline for replacement at within 17 months after the AD becomes effective (Compliance).\n\n**Why CASA says this is required (stated rationale):**\n\n- The background states the existing steel ball bearings can corrode. If the primary aileron control path experiences abnormal conditions, corroded bearings in the override quadrant could disable the secondary control path and reduce lateral controllability. The replacement part uses CRES bearings to reduce the corrosion risk (Background).\n\n**Who is affected and who pays:**\n\n- Affected parties: owners and operators of the specified Boeing 767 aircraft (line numbers 1–836). Maintenance organisations performing the work will also be involved.\n- Who pays: the aircraft owner/operator pays for parts, labour and any aircraft downtime needed to comply. If operators use third‑party maintenance providers, they pay those providers for the work.\n\n**What is required of operators (behaviour changes):**\n\n- Schedule and perform the modification within 17 months of the AD taking effect, using the procedures in Boeing Alert Service Bulletin 767-27A0175.\n- Do not install the old-style override quadrant on any affected aircraft after the AD takes effect.\n\n**Instructions and decision-makers:**\n\n- The Civil Aviation Safety Authority (CASA) delegate issued the AD under subregulation 39.1(1) of CASR 1998; the AD sets the legal requirement.\n- Boeing’s Alert Service Bulletin provides the technical instructions for the replacement; maintenance providers must follow those instructions to accomplish the AD.\n\n**Costs, incentives and trade-offs (practical effects):**\n\n- Direct costs: purchase of the modified assembly, labour to fit it, and aircraft downtime while the work is done. These are immediate, concentrated costs borne by operators of the affected fleet (Requirement & Compliance).\n- Supply and scheduling risk: the AD depends on availability of the modified units and the capacity of authorised maintenance providers. If supply or MRO capacity is constrained, operators may face delays or higher prices for earlier slots.\n- Operational trade-off: compliance improves redundancy in the aileron override mechanism (per Background) but requires diverting maintenance resources and aircraft time that could otherwise be used for other work or revenue flights.\n- Competitive/market effect: demand for the approved replacement parts and for maintenance to carry out the work will rise temporarily. This benefits authorised parts suppliers and maintenance providers able to perform the task; independent MROs can compete to do the work provided they follow the service bulletin and regulatory requirements.\n\n**Implementation and enforcement risks:**\n\n- Enforcement is binary and time-limited: aircraft must be modified within 17 months; unmodified parts cannot be installed from the effective date. Failure to comply risks regulatory action or grounding.\n- The AD references an external technical document (Boeing Alert Service Bulletin 767-27A0175) and an FAA AD (Note 2). Operators must obtain and follow the Boeing bulletin to meet the AD. If the bulletin is updated or parts drawings are revised, operators will need to ensure they use the correct revision.\n\n**Notes and limits in the text:**\n\n- The AD explicitly states it does not require the actions of Boeing Service Bulletin 767-27-0142 (Note 1), so operators are not obliged to do that earlier Boeing bulletin as part of this directive.\n- The AD cross-references FAA AD 2003-15-03 (Note 2), which may contain related requirements or background but does not replace this CASA requirement.\n\n**Concrete risk and incentive summary:**\n\n- Who decides: CASA sets the mandatory timetable and technical reference; Boeing provides the modification instructions.\n- Who pays: operators bear the costs of parts, labour and downtime.\n- Behaviour change: compulsory replacement of a specific component within a set time, plus a ban on reinstalling the unmodified part.\n- Potential unintended consequences: short-term supply or MRO bottlenecks and reallocation of maintenance resources; otherwise the AD is narrowly targeted at a specific safety hazard (Background).\n\n(References: Applicability; Requirement 1 and 2; Compliance; Background; Notes 1–2.)"},"flash_summary_failed":{"failed":true,"reason":"Unauthenticated. Configure AI_GATEWAY_API_KEY or use a provider module. Learn more: https://ai-sdk.dev/unauthenticated-ai-gateway","source":"analysis-cron"},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This Airworthiness Directive maintains its original narrow scope. It addresses a specific unsafe condition in a particular aircraft component and mandates a targeted replacement. There is no evidence of scope creep; the directive remains focused on the original safety issue identified (corroded steel ball bearings in the aileron override quadrant mechanism)."},"complexity_factors":["Single, clearly defined mechanical component subject to the directive","Only two substantive requirements (replacement and installation prohibition)","Limited applicability (specific Boeing 767 models, line numbers 1-836)","Straightforward compliance timeline (17 months for replacement, immediate for prohibition)","Minimal cross-referencing (one Boeing Service Bulletin, one FAA AD reference in notes only)","No nested exceptions or conditional logic","Short document (1 page), plain language background section explaining the safety rationale"],"plain_english_summary":"This safety order requires operators of early-production Boeing 767-200/-300/-300F (line numbers 1–836) to replace the aileron control override quadrant because its steel ball bearings can corrode and jam the backup aileron control, risking loss of lateral control. Unmodified quadrants are banned immediately (effective 2 Oct 2003); replacements with corrosion-resistant bearings must be installed per Boeing instructions within 17 months. This action eliminates the corrosion-related failure mode in the backup steering system."}},"importantCases":[],"_links":{"self":"/api/acts/ad-b767-189-aileron-control-override-quadrant-replacement","history":"/api/acts/ad-b767-189-aileron-control-override-quadrant-replacement/history","analysis":"/api/acts/ad-b767-189-aileron-control-override-quadrant-replacement/analysis","conflicts":"/api/acts/ad-b767-189-aileron-control-override-quadrant-replacement/conflicts","importantCases":"/api/acts/ad-b767-189-aileron-control-override-quadrant-replacement/important-cases","documents":"/api/acts/ad-b767-189-aileron-control-override-quadrant-replacement/documents"}}