{"id":"F2009L00087","name":"AD/B747/389 - Trailing Edge Flap Tracks and Track Main Carriage","slug":"ad-b747-389-trailing-edge-flap-tracks-and-track-main-carriage","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":76502,"registerId":"commonwealth-F2009L00087-current","compilationNumber":null,"startDate":"2026-04-02","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/B747/389 | Trailing Edge Flap Tracksand Track Main Carriage | 2/2009 |\n| ----------- | ------------------------------------------------ | ------ |\n\n| Applicability: | All 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 2008-25-07 Amdt 39-15765.Note: Boeing Alert Service Bulletin 747-57A2323 original issue, or later FAA approved revision, refers.                                                                                                                                                                                                                                                                                                                                      |\n| Compliance:    | As specified in the Requirement document, with a revised effective date of12 February 2009.                                                                                                                                                                                                                                                                                                                                                                                                                                          |\n|                | This Airworthiness Directive becomes effective on 12 February 2009.                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |\n| Background:    | The FAA issued AD 2008-25-07 as a result from a detailed structural analysis of the trailing edge flap attach structural and fail-safe components; accomplished as a result of a dynamic stability and control analysis, which could not demonstrate continued safe flight and landing of the aircraft after the loss of a trailing edge flap. This Directive requires repetitive inspections of the flap tracks attachment and the flap tracks, and for certain aircraft, modification of the fail-safe links of the main carriage. |\n\n![](image.001.png)  \nDavid Punshon  \nDelegate of the Civil Aviation Safety Authority\n\n17 December 2008","sortOrder":0},{"sectionNumber":"AD/B747/389","sectionType":"part","heading":"AD/B747/389","content":"## AD/B747/389","sortOrder":1},{"sectionNumber":"Trailing Edge Flap Tracksand Track Main ","sectionType":"part","heading":"Trailing Edge Flap Tracksand Track Main Carriage","content":"## Trailing Edge Flap Tracks  \nand Track Main Carriage","sortOrder":2},{"sectionNumber":"2/2009","sectionType":"part","heading":"2/2009","content":"## 2/2009","sortOrder":3}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This is a standard airworthiness directive implementing a foreign aviation safety requirement. It maintains its original narrow scope: addressing a specific structural safety issue on specific Boeing 747 models. There is no evidence of scope creep or expansion beyond the original safety purpose."},"complexity_factors":["Very short document (under 300 words)","Only 2 substantive operative provisions: inspection requirement and modification requirement for certain aircraft","Heavy reliance on external documents (FAA AD 2008-25-07 and Boeing Service Bulletin 747-57A2323) — the actual technical requirements are not reproduced in the text","No defined terms section; minimal conditional logic ('for certain aircraft')","Simple applicability table format with clear aircraft model listing","Single compliance date with reference to external schedule"],"plain_english_summary":"This mandatory CASA Airworthiness Directive requires operators of Boeing 747-100/200/300/400 and 747SR series in Australia to inspect trailing edge flap tracks — and, for some aircraft, modify fail‑safe links — per the referenced FAA/Boeing procedures. It addresses structural fatigue that could allow a flap to separate in flight, risking controllability and safe landing. Compliance is legally required from 12 February 2009."},"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":false,"description":"The directive adopts the technical requirements of FAA AD 2008-25-07 and the Boeing Alert Service Bulletin for the listed 747 models. The instrument does not expand substantive scope; the only explicit local change noted is a revised effective date of 12 February 2009 (Compliance)."},"complexity_factors":["Cross-reference dependency: mandates compliance with FAA AD 2008-25-07 and Boeing Alert Service Bulletin rather than setting detailed local steps, requiring operators to obtain and follow external documents (Requirement).","Technical workscope: repetitive structural inspections and, for some aircraft, fail‑safe link modifications require certified maintenance capability and parts availability (Background; Requirement).","Fleet heterogeneity: applies across many 747 variants (-100 to -400 and -SR), but modification requirement applies only to ‘certain aircraft,’ creating case‑by‑case assessment (Applicability; Requirement).","Operational impact: repetitive inspections imply ongoing maintenance scheduling and possible aircraft downtime, which affects operators’ costs and operations (Requirement; Compliance).","Regulatory timing: revised effective date (12 February 2009) imposes a firm compliance start date that operators must meet (Compliance).","Enforcement and discretion: CASA adopts the FAA AD; CASA/Delegate enforces compliance, but technical approval may involve FAA‑approved revisions of the service bulletin (Requirement)."],"plain_english_summary":"This Airworthiness Directive requires operators of specified Boeing 747 models to perform repetitive inspections of trailing‑edge flap tracks and their attachments and, for some aeroplanes, to modify the fail‑safe links of the main carriage by following FAA AD 2008-25-07 and the referenced Boeing service bulletin. It takes effect 12 February 2009. Operators/owners of the listed 747 series must carry out and pay for the inspections/modifications; CASA enforces compliance. The action follows an FAA analysis that could not demonstrate continued safe flight and landing after loss of a trailing‑edge flap."},"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"}},"importantCases":[],"_links":{"self":"/api/acts/ad-b747-389-trailing-edge-flap-tracks-and-track-main-carriage","history":"/api/acts/ad-b747-389-trailing-edge-flap-tracks-and-track-main-carriage/history","analysis":"/api/acts/ad-b747-389-trailing-edge-flap-tracks-and-track-main-carriage/analysis","conflicts":"/api/acts/ad-b747-389-trailing-edge-flap-tracks-and-track-main-carriage/conflicts","importantCases":"/api/acts/ad-b747-389-trailing-edge-flap-tracks-and-track-main-carriage/important-cases","documents":"/api/acts/ad-b747-389-trailing-edge-flap-tracks-and-track-main-carriage/documents"}}