{"id":"F2008L04560","name":"AD/B747/62 Amdt 3 - Flap Carriage Spindles and Aft Link Assembly","slug":"ad-b747-62-amdt-3-flap-carriage-spindles-and-aft-link-assembly","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":120861,"registerId":"commonwealth-F2008L04560-current","compilationNumber":null,"startDate":"2026-04-03","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Boeing 747 Series Aeroplanes","sectionType":"division","heading":"Boeing 747 Series Aeroplanes","content":"### Boeing 747 Series Aeroplanes\n\n| AD/B747/62 Amdt 3 | Flap Carriage Spindles and Aft Link Assembly | 1/2009 |\n| ----------------- | -------------------------------------------- | ------ |\n\n| Applicability: | Model 747-100, -100B, -100B SUD, -200B, -200C, -200F, -300, -400, -400D, -400F, and 747SR series aircraft. |\n| -------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement: | Action in accordance with the technical requirements of FAA AD 2008-22-17 Amdt 39-15714. |\n| Compliance: | As specified in the Requirement document, with a revised effective date of15 January 2009. |\n| | This Amendment becomes effective on 15 January 2009. |\n| Background: | In an overseas incident, undetected stress corrosion caused failure of two spindles on one flap which resulted in severe handling difficulties. Fractured flap carriage aft links have also been detected overseas.Amendment 1 referenced Revision 2 of the Requirement document which requires inspection and overhaul of aft link assemblies, additional inspections, revised compliance intervals and requirement to overhaul or replace spindles.Amendment 2 required additional work, i.e. internal inspection of the spindles. It also referenced the superseding FAA AD as the Requirement document due to the requirement and compliance diverging from Boeing Service Bulletin 747-27-2280 Revision 3.Amendment 3 is issued in response to a new FAA AD, which adds a repetitive inspection to detect broken parts, and revises the overhaul threshold and repetitive intervals. The FAA AD results from analysis that showed additional inspections should be done to prevent the loss of a flap, and that the flight-hour-based interval should be revised to a flight-cycle-based interval, because the greatest loads on the spindles happen during takeoff and landing. |\n\n![](image.001.png) \nDavid Villiers \nDelegate of the Civil Aviation Safety Authority\n\n27 November 2008","sortOrder":0},{"sectionNumber":"AD/B747/62 Amdt 3","sectionType":"part","heading":"AD/B747/62 Amdt 3","content":"## AD/B747/62 Amdt 3","sortOrder":1},{"sectionNumber":"Flap Carriage Spindles and Aft Link Asse","sectionType":"part","heading":"Flap Carriage Spindles and Aft Link Assembly","content":"## Flap Carriage Spindles and Aft Link Assembly","sortOrder":2},{"sectionNumber":"1/2009","sectionType":"part","heading":"1/2009","content":"## 1/2009","sortOrder":3}],"analysis":{"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":3,"scope_assessment":{"changed":false,"description":"This Airworthiness Directive remains tightly scoped to its original purpose: ensuring the structural integrity of flap carriage spindles and aft link assemblies on Boeing 747 aircraft. While Amendment 3 adds new inspection requirements and revises maintenance intervals, these changes respond to evolving safety data about the same mechanical issue — they do not expand the directive to cover unrelated aircraft systems or different aircraft types. The scope has deepened (more thorough inspections) but not broadened beyond the original safety concern."},"complexity_factors":["Short, single-purpose document (one specific mechanical issue on one aircraft family)","Minimal defined terms (relies on external FAA AD for technical specifications)","No nested legislative cross-references within the instrument itself","Simple conditional structure: applicability test → requirement → compliance date","Technical complexity is outsourced to the referenced FAA AD (2008-22-17), keeping the Australian instrument itself brief","Clear effective date and compliance timeline specified"],"plain_english_summary":"This AD mandates repetitive inspections and cycle-based overhaul or replacement of wing flap carriage spindles and aft link assemblies on certain Boeing 747 series after stress-corrosion failures and broken aft links were found overseas. It replaces time-based intervals with flight-cycle schedules to detect damage earlier and prevent flap detachment or loss of control. It applies to operators of the affected 747 models (including foreign aircraft while operating in Australia)."},"flash_summary":{"complexity_score":6,"scope_assessment":{"changed":true,"description":"Amendment 3 expands and alters the original scope by adding repetitive inspections to detect broken parts and revising overhaul thresholds and inspection intervals — notably switching the interval basis from flight-hours to flight-cycles — thereby broadening the maintenance and monitoring obligations on operators (Background; Requirement)."},"complexity_factors":["Direct incorporation and reliance on an overseas regulatory instrument (FAA AD 2008-22-17) rather than a standalone domestic standard (Requirement).","Multiple amendment history requiring layer-by-layer interpretation (Amendments 1–3 referenced in Background).","Change in compliance metric from flight-hours to flight-cycles, requiring operators to track different usage data (Background).","Introduction of repetitive inspections and revised overhaul thresholds and intervals, increasing operational scheduling complexity (Background).","Applicability across numerous Boeing 747 variants, widening the population of affected operators (Applicability).","Divergence from manufacturer service bulletin referenced previously, creating potential alignment and compliance questions (Background).","Compliance effective date and mandatory timing obligations impose near-term logistical and cost burdens on operators (Compliance/Requirement)."],"plain_english_summary":"This amendment requires operators of specified Boeing 747 models to carry out inspections, internal inspections, overhauls or replacements of flap carriage spindles and aft link assemblies in line with FAA AD 2008-22-17, effective 15 January 2009. (Requirement)\n\nCASA enforces the requirement; aircraft operators pay for the inspections and repairs and must shift maintenance planning from flight-hours to flight-cycles, add repetitive inspections to detect broken parts, and meet revised overhaul thresholds. (Background)"}},"importantCases":[],"_links":{"self":"/api/acts/ad-b747-62-amdt-3-flap-carriage-spindles-and-aft-link-assembly","history":"/api/acts/ad-b747-62-amdt-3-flap-carriage-spindles-and-aft-link-assembly/history","analysis":"/api/acts/ad-b747-62-amdt-3-flap-carriage-spindles-and-aft-link-assembly/analysis","conflicts":"/api/acts/ad-b747-62-amdt-3-flap-carriage-spindles-and-aft-link-assembly/conflicts","importantCases":"/api/acts/ad-b747-62-amdt-3-flap-carriage-spindles-and-aft-link-assembly/important-cases","documents":"/api/acts/ad-b747-62-amdt-3-flap-carriage-spindles-and-aft-link-assembly/documents"}}