{"id":"F2007L02183","name":"AD/B747/357 - Station 400 Upper Deck Floor Beam","slug":"ad-b747-357-station-400-upper-deck-floor-beam","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":67411,"registerId":"commonwealth-F2007L02183-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/B747/357 | Station 400 Upper Deck Floor Beam | 8/2007 |\n| ----------- | --------------------------------- | ------ |\n\n| Applicability: | Model 747-400 series aircraft, as identified in Boeing Alert Service Bulletin747-53A2660, dated 16 November 2006, or later FAA approved revision.                                                                                                                                                                   |\n| -------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | Action in accordance with the technical requirements of FAA AD 2007-10-09 Amdt 39-15050.                                                                                                                                                                                                                            |\n| Compliance:    | As specified in the Requirement document, with a revised effective date of2 August 2007.                                                                                                                                                                                                                            |\n|                | This Airworthiness Directive becomes effective on 2 August 2007.                                                                                                                                                                                                                                                    |\n| Background:    | The FAA received several reports of fatigue cracking in upper deck floor beams made from 7000 series aluminium alloy. Undetected cracking in the upper deck floor beam at station 400 could extend and sever the floor beam, which could result in loss of controllability and rapid decompression of the aircraft. |\n\n![](image.001.png)  \nDavid Villiers  \nDelegate of the Civil Aviation Safety Authority\n\n19 June 2007","sortOrder":0},{"sectionNumber":"AD/B747/357","sectionType":"part","heading":"AD/B747/357","content":"## AD/B747/357","sortOrder":1},{"sectionNumber":"Station 400 Upper Deck Floor Beam","sectionType":"part","heading":"Station 400 Upper Deck Floor Beam","content":"## Station 400 Upper Deck Floor Beam","sortOrder":2},{"sectionNumber":"8/2007","sectionType":"part","heading":"8/2007","content":"## 8/2007","sortOrder":3}],"analysis":{"flash_summary_failed":{"failed":true,"reason":"A positive credit balance is required for all requests, including BYOK, so fallback providers remain available. Add credits at https://vercel.com/d?to=%2F%5Bteam%5D%2F%7E%2Fai%3Fmodal%3Dtop-up to continue.","source":"analysis-cron"},"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":false,"description":"The directive adopts the corrective actions of FAA AD 2007-10-09 for 747-400 aircraft identified in Boeing Alert Service Bulletin 747-53A2660; the text revises the effective date to 2 August 2007 but does not expand the set of affected aircraft or the core mandated actions."},"complexity_factors":["Cross-reference to FAA AD 2007-10-09 and Boeing Alert Service Bulletin 747-53A2660 creates dependence on external documents (Requirement; Applicability).","Safety-critical structural issue: inspections/repairs concern fatigue cracking in 7000-series aluminium upper-deck floor beams (Background).","Narrow applicability requiring precise aircraft identification per the service bulletin (Applicability).","Reliance on later FAA-approved revisions of the service bulletin introduces ongoing compliance tracking (Applicability).","Compliance timing set by a revised effective date (Compliance) which can compress operator planning.","Operational and maintenance burden falls on aircraft operators to perform inspections/repairs as specified (Requirement)."],"plain_english_summary":"Requires operators of Boeing 747-400 aircraft identified in Boeing Alert Service Bulletin 747‑53A2660 (16 Nov 2006 or later FAA‑approved revision) to carry out the inspections and corrective actions set out in FAA AD 2007‑10‑09. Effective 2 August 2007. The directive responds to reports of fatigue cracking in 7000‑series aluminium upper‑deck floor beams at station 400; undetected cracks could sever the beam and risk loss of control and rapid decompression."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a standard, narrow Airworthiness Directive addressing a specific safety defect in a specific aircraft model. It has not expanded beyond its original purpose of mandating inspection/repair of fatigue cracking in 747-400 upper deck floor beams."},"complexity_factors":["Very short document (approximately 200 words of substantive content)","Only 1 defined term implicitly referenced (Station 400 — a structural location identifier)","No nested conditional logic or exceptions","Single cross-reference to external FAA document (AD 2007-10-09) — the technical complexity is outsourced","Clear, direct applicability statement (specific aircraft model only)","No internal definitions section or interpretation clauses"],"plain_english_summary":"This AD mandates inspections and repairs for fatigue cracking in the upper-deck floor beams at Station 400 on Boeing 747-400s. It requires operators to follow the FAA’s specified inspection and corrective procedures.\n\nUnrepaired cracking could lead to floor-beam failure with possible loss of controllability or rapid cabin decompression. Compliance with FAA AD 2007-10-09 was required from 2 August 2007."}},"importantCases":[],"_links":{"self":"/api/acts/ad-b747-357-station-400-upper-deck-floor-beam","history":"/api/acts/ad-b747-357-station-400-upper-deck-floor-beam/history","analysis":"/api/acts/ad-b747-357-station-400-upper-deck-floor-beam/analysis","conflicts":"/api/acts/ad-b747-357-station-400-upper-deck-floor-beam/conflicts","importantCases":"/api/acts/ad-b747-357-station-400-upper-deck-floor-beam/important-cases","documents":"/api/acts/ad-b747-357-station-400-upper-deck-floor-beam/documents"}}