{"id":"F2009L02865","name":"AD/B747/131 Amdt 1 - Flap Control Unit Wiring Change","slug":"ad-b747-131-amdt-1-flap-control-unit-wiring-change","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":80210,"registerId":"commonwealth-F2009L02865-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/B747/131 Amdt 1 | Flap Control Unit Wiring Change | 8/2009 |\n| ------------------ | ------------------------------- | ------ |\n\n| Applicability: | Model 747-400 series aeroplanes having line numbers 696 through 1036 inclusive.                                                                                                                                                                                                                                                                                            |\n| -------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | 1. For aeroplanes having line numbers 696 through 1019 inclusive and 1021 through 1026 inclusive, unless previously accomplished in accordance with AD/B747/131 (FAA AD 94-14-21), revise the input wiring for the flap control unit (FCU) in accordance with Boeing Service Bulletin SB 747-27A2346, Revision 1, dated 19 May 1994, or Revision 2, dated 12 January 1995. |\n|                | 2. For aeroplanes having line numbers 1020, and 1027 through 1036 inclusive, unless previously accomplished, revise the input wiring for the FCU in accordance with SB 747-27A2346, Revision 2.                                                                                                                                                                            |\n|                | 3. For aeroplanes having line numbers 696 through 1036 inclusive, unless previously accomplished, perform the additional systems test for the wiring of the trailing edge flap in accordance with SB 747-27A2346, Revision 2.                                                                                                                                              |\n|                | Later revisions of the SB 747-27A2346, Revision 2, approved by the United States Federal Aviation Administration (FAA) as an Alternate Method of Compliance (AMOC) to FAA AD 95-12-27 are considered acceptable for compliance with the equivalent Requirements of this Amendment.                                                                                         |\n|                | Note: FAA AD 95-12-27 Amdt 39-9280 refers.                                                                                                                                                                                                                                                                                                                                 |\n| Compliance:    | For Requirements 1 through 3 - Within 60 days after the effective date of this Amendment.                                                                                                                                                                                                                                                                                  |\n|                | This Amendment becomes effective on 30 July 2009.                                                                                                                                                                                                                                                                                                                          |\n| Background:    | The FAA received reports of disconnection of the Landing Gear Module electrical connectors, this disconnection can result in the loss of the primary, secondary and alternate control of the flaps. Compliance with the initial issue of this Directive decreased the likelihood of an all-up-flaps landing due to the loss of control of all flap operations.             |\n\n|     | Subsequently the FAA received a report indicating that a wiring error was not detected by the system test required by the existing Directive. This Amendment requires a new systems test for the wiring of the trailing edge flap and also expands the applicability of the existing Directive to include additional aeroplanes. |\n| --- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n|     | The original issue of this Directive became effective on 15 September 1994.                                                                                                                                                                                                                                                      |\n\n![](image.001.png)  \nJames Coyne  \nDelegate of the Civil Aviation Safety Authority\n\n16 June 2009","sortOrder":0},{"sectionNumber":"AD/B747/131 Amdt 1","sectionType":"part","heading":"AD/B747/131 Amdt 1","content":"## AD/B747/131 Amdt 1","sortOrder":1},{"sectionNumber":"Flap Control Unit Wiring Change","sectionType":"part","heading":"Flap Control Unit Wiring Change","content":"## Flap Control Unit Wiring Change","sortOrder":2},{"sectionNumber":"8/2009","sectionType":"part","heading":"8/2009","content":"## 8/2009","sortOrder":3}],"analysis":{"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":true,"description":"This amendment expands the applicability of the original directive to include additional aeroplanes within line numbers 696–1036 and adds a new systems test for the trailing‑edge flap wiring after reports that the earlier test could miss a wiring error. It also permits later FAA‑approved revisions of Boeing SB 747‑27A2346 as acceptable AMOCs."},"complexity_factors":["Limited and specific applicability by aircraft line numbers (696–1036) increases tracking but narrows scope","Multiple acceptable service bulletin revisions (Rev 1, Rev 2, and later FAA‑approved AMOCs) require document management","Three distinct mandatory actions: two wiring-revision groups (by line-number subsets) plus an additional systems test","Short compliance window (60 days) creates scheduling and operational disruption pressure for operators","Interaction with prior AD compliance (exemption if previously accomplished per AD/B747/131 or FAA AD 94‑14‑21) requires record checks"],"plain_english_summary":"Requires specified Boeing 747‑400 aeroplanes (line numbers 696–1036 as listed) to have the flap control unit (FCU) input wiring revised and to undergo an additional trailing‑edge flap systems test, using Boeing Service Bulletin SB 747‑27A2346 (specified revisions). (Requirements 1–3; Compliance)\n\nOperators must complete the wiring change and system test within 60 days of the amendment’s effective date. Later FAA‑approved revisions of the service bulletin are acceptable as alternate methods of compliance (AMOC)."},"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":true,"description":"This Amendment expands the scope of the original 1994 directive in two ways: (1) it extends applicability to additional aircraft line numbers (1027-1036) not covered by the original issue, and (2) it adds a new mandatory systems test requirement after discovering the original test was inadequate. The directive has grown from a simple wiring modification to a more comprehensive safety fix with enhanced verification requirements."},"complexity_factors":["Multiple applicability groups based on production line numbers (696-1019/1021-1026 vs 1020/1027-1036)","Cross-references to external documents: Boeing Service Bulletin 747-27A2346 (Revisions 1 and 2), FAA AD 94-14-21, and FAA AD 95-12-27","Conditional compliance language ('unless previously accomplished')","Nested structure: Amendment 1 modifies original AD/B747/131 from 1994","Acceptance of foreign regulatory approvals (FAA AMOCs) as equivalent compliance"],"plain_english_summary":"This AD mandates rewiring and a new, more rigorous systems test of the flap control unit on certain Boeing 747-400s (production line numbers 696–1036) to correct a wiring error that can cause total loss of flap control. \n\nIt affects owners/operators of those aircraft, must be done per Boeing Service Bulletin 747-27A2346, and required completion within 60 days of 30 July 2009, expanding a 1994 order."}},"importantCases":[],"_links":{"self":"/api/acts/ad-b747-131-amdt-1-flap-control-unit-wiring-change","history":"/api/acts/ad-b747-131-amdt-1-flap-control-unit-wiring-change/history","analysis":"/api/acts/ad-b747-131-amdt-1-flap-control-unit-wiring-change/analysis","conflicts":"/api/acts/ad-b747-131-amdt-1-flap-control-unit-wiring-change/conflicts","importantCases":"/api/acts/ad-b747-131-amdt-1-flap-control-unit-wiring-change/important-cases","documents":"/api/acts/ad-b747-131-amdt-1-flap-control-unit-wiring-change/documents"}}