{"id":"F2006B03268","name":"AD/B747/90 Amdt 1 - Trailing Edge Flap Track","slug":"ad-b747-90-amdt-1-trailing-edge-flap-track","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":42692,"registerId":"commonwealth-F2006B03268-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/B747/90 Amdt 1 - Trailing Edge Flap Track","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)  \n\nAIRWORTHINESS DIRECTIVE\n\n![](image.001.png)\n\n![](image.001.png)  \nFor the reasons set out in the background section, the CASA delegate whose signature appears below revokes Airworthiness Directive AD/B747/90 and issues the following AD under subregulation 39.1 (1) of CAR 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\nBoeing 747 Series Aeroplanes\n\nAD/B747/90\n\nAmdt 1\n\n  \nTrailing Edge Flap Track 3/2003\n\nApplicability: Model 747 series aircraft, as listed in Boeing Service Bulletin 747-57-2256 Revision 3, dated 21 June 2001.\n\nRequirement: Action in accordance with the technical requirements of FAA AD 2002-23-21 Amdt 39-12965.\n\nNote: Boeing Service Bulletins 747-57-2256, 747-57-2256 Revision 1, 747-57-2256\n\nRevision 2, and 747-57-2256 Revision 3 refer.\n\nCompliance: As specified in the Requirement document, with a revised effective date of 20 March 2003.\n\nThis Amendment becomes effective on 20 March 2003.\n\nBackground: The FAA received reports of missing cadmium plating, and corrosion in certain flap track fail-safe bar bolt holes. This condition, if not corrected, could result in fracture of the trailing edge flap track, separation of the flap supported by the track, and consequent reduction in controllability of the aircraft.\n\nAmendment 1 is issued in response to a new FAA AD which was prompted by reports of corrosion and cracks found in certain bolt holes reworked to the requirements of the original issue of this Directive (existing FAA AD).\n\nThe original issue of this Airworthiness Directive became effective on 18 April 1991.\n\n![Signature of David Villiers, Delegate of the Civil Aviation Safety Authority.](image.002.png)  \n\nDavid Alan Villiers\n\nDelegate of the Civil Aviation Safety Authority 30 January 2003\n\n![](image.001.png)\n\nThe above AD is notified in the Commonwealth of Australia Gazette on 26 February 2003.\n\n  \n\nPage 1 of 1","sortOrder":0}],"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"},"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":true,"description":"Amendment 1 replaces the original AD and requires action “in accordance with the technical requirements of FAA AD 2002-23-21” and references Boeing Service Bulletin 747-57-2256 Revision 3 (Requirement). The Background states the change was prompted by reports of corrosion and cracks found in bolt holes reworked under the original AD (Background). Concretely, the Amendment updates and broadens required inspections/repairs and sets a new effective date (20 March 2003), altering the prior corrective regime."},"complexity_factors":["Normative reliance on an external FAA AD (FAA AD 2002-23-21) for technical requirements — compliance depends on another instrument.","References to multiple Boeing Service Bulletin revisions (747-57-2256 and Revs 1–3) increase document-tracking burden for operators.","Technical inspections and possible rework/repairs of critical structural components (flap track fail-safe bar bolt holes) require specialised maintenance and engineering input.","Applicability limited to aircraft listed in the service bulletin — operators must check fleet records to determine applicability.","Revoke-and-replace structure: this Amendment revokes the prior AD and imposes a revised effective date (20 March 2003), creating a deadline-driven compliance obligation.","Operational impact: inspections/repairs can cause aircraft downtime and resource allocation for maintenance organisations."],"plain_english_summary":"**AD/B747/90 Amendment 1** requires operators of certain Boeing 747 series aircraft (those listed in Boeing Service Bulletin 747‑57‑2256 Revision 3) to carry out the inspections and corrective actions specified in FAA AD 2002‑23‑21 for trailing‑edge flap track bolt holes. CASA set a revised effective date of 20 March 2003.\n\nThe amendment replaces the earlier AD after reports that missing cadmium plating, corrosion and cracks were found in bolt holes that had been reworked under the original directive."},"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This amendment stays tightly focused on its original purpose — addressing a specific mechanical defect in Boeing 747 flap tracks. While it updates the technical requirements to reflect new evidence that the original repair was insufficient, it does not expand to cover other aircraft types, other components, or broader operational issues. The scope remains precisely targeted at the same safety risk identified in 1991."},"complexity_factors":["Short, single-purpose document (1 page)","Only 4 structural sections (Applicability, Requirement, Compliance, Background)","Heavy reliance on external documents — the actual technical work is contained in referenced FAA AD 2002-23-21 and Boeing Service Bulletins, not reproduced here","No defined terms section — uses standard aviation terminology without local definitions","Simple conditional logic: if you operate this aircraft model, you must comply","No nested exceptions or complex compliance pathways"],"plain_english_summary":"This Airworthiness Directive requires operators of certain Boeing 747s (those covered by Boeing Service Bulletin 747-57-2256 Rev 3) to inspect and correct corrosion and missing cadmium plating on trailing-edge flap tracks. It updates a 1991 fix that proved inadequate, adopts the FAA’s revised remedy (AD 2002-23-21), and mandates re‑inspection and proper repair or replacement to prevent flap failure and potential loss of aircraft control. Effective 20 March 2003."}},"importantCases":[],"_links":{"self":"/api/acts/ad-b747-90-amdt-1-trailing-edge-flap-track","history":"/api/acts/ad-b747-90-amdt-1-trailing-edge-flap-track/history","analysis":"/api/acts/ad-b747-90-amdt-1-trailing-edge-flap-track/analysis","conflicts":"/api/acts/ad-b747-90-amdt-1-trailing-edge-flap-track/conflicts","importantCases":"/api/acts/ad-b747-90-amdt-1-trailing-edge-flap-track/important-cases","documents":"/api/acts/ad-b747-90-amdt-1-trailing-edge-flap-track/documents"}}