{"id":"F2009L02839","name":"AD/B747/314 Amdt 2 - Aft Pressure Bulkhead Web","slug":"ad-b747-314-amdt-2-aft-pressure-bulkhead-web","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":80132,"registerId":"commonwealth-F2009L02839-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/B747/314 Amdt 2 | Aft Pressure Bulkhead Web | 8/2009 |\n| ------------------ | ------------------------- | ------ |\n\n| Applicability: | Model 747-100, -100B, -100B SUD, -200B, -200C, -200F, -300, -400, -400D, -400F, 747SP and 747SR series aircraft; except those aircraft that have been converted to a Model 747-400 LCF configuration.                                                                                                                                                                                                                                                                                                                                     |\n| -------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | Action in accordance with the technical requirements of Corrected FAA AD2009-04-06 Amdt 39-15812.                                                                                                                                                                                                                                                                                                                                                                                                                                         |\n|                | Note: Boeing Alert Service Bulletins 747-53A2482 original issue or 747-53A2482 Revision 1, or later FAA approved revision, refers.                                                                                                                                                                                                                                                                                                                                                                                                        |\n| Compliance:    | As specified in the Requirement document, with a revised effective date of30 July 2009.                                                                                                                                                                                                                                                                                                                                                                                                                                                   |\n|                | This Amendment becomes effective on 30 July 2009.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |\n| Background:    | The FAA required certain actions to detect and correct the propagation of fatigue cracks in the vicinity of ‘oil cans’ on the web of the aft pressure bulkhead, which could result in rapid decompression and over-pressurisation of the tail section, and consequent loss of control of the aircraft.Amendment 1 required a reduced compliance time for the initial detailed inspection, and revised applicability.Amendment 2 is issued in response to a corrected FAA AD, which corrects the text of paragraphs (i) and (j) of the AD. |\n\n![](image.001.png)  \nDavid Villiers  \nDelegate of the Civil Aviation Safety Authority\n\n18 June 2009","sortOrder":0},{"sectionNumber":"AD/B747/314 Amdt 2","sectionType":"part","heading":"AD/B747/314 Amdt 2","content":"## AD/B747/314 Amdt 2","sortOrder":1},{"sectionNumber":"Aft Pressure Bulkhead Web","sectionType":"part","heading":"Aft Pressure Bulkhead Web","content":"## Aft Pressure Bulkhead Web","sortOrder":2},{"sectionNumber":"8/2009","sectionType":"part","heading":"8/2009","content":"## 8/2009","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":5,"scope_assessment":{"changed":true,"description":"Yes. Amendment 1 shortened the initial inspection compliance time and revised the AD's applicability to certain 747 models; Amendment 2 amends the AD text by correcting paragraphs (i) and (j) of the FAA AD. These changes alter which aircraft and what timeframes are covered compared to the original AD text (Background / Compliance)."},"complexity_factors":["Cross-reference to a corrected FAA AD (AD2009-04-06): requires operators to follow an external instrument rather than only domestic text (Requirement).","Dependence on Boeing Alert Service Bulletins (original or Revision 1, or later FAA-approved revision): multiple document versions affect compliance choices (Requirement / Note).","Broad but exception-based applicability across many 747 variants, with a specific exclusion for 747-400 LCF conversions: determining whether an aircraft is in scope can be non-trivial for operators (Applicability).","Revised effective/compliance dates and a reduced initial inspection interval introduced by Amendment 1, increasing scheduling and operational pressure (Compliance / Background).","Amendment 2 corrects drafting errors in specified AD paragraphs (i) and (j), creating a need to reconcile versions and ensure the corrected text is followed (Background).","Safety-critical subject matter (risk of rapid decompression and loss of control) raises urgency and potential operational impacts, increasing compliance burdens and risk-management complexity (Background)."],"plain_english_summary":"Requires operators of most Boeing 747 variants (except aircraft converted to 747-400 LCF) to perform inspections and corrective work set out in the corrected FAA Airworthiness Directive (AD2009-04-06) and the referenced Boeing service bulletins, targeting fatigue cracks on the aft pressure bulkhead web. It matters because the inspections and repairs aim to prevent rapid decompression and potential loss of control; operators bear inspection and repair costs, face shortened inspection timeframes, and must follow the corrected AD text."},"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This airworthiness directive maintains its original narrow scope: addressing fatigue cracks in the aft pressure bulkhead web of Boeing 747 aircraft. Amendment 2 is purely technical and administrative — it corrects paragraph references (i) and (j) in the adopted FAA directive without expanding the aircraft models covered, the nature of the safety defect, or the required actions. The scope remains tightly focused on the specific structural integrity issue identified in the original directive."},"complexity_factors":["Short, single-purpose instrument (approximately 250 words)","Only 3 defined elements: applicability, requirement, and compliance","Heavy reliance on external documents (FAA AD 2009-04-06 and Boeing Service Bulletin 747-53A2482) — the actual technical requirements are not reproduced in the text","No nested conditional logic or exceptions within the instrument itself","Simple amendment structure (Amendment 2 only corrects cross-referenced paragraph numbers from the FAA original)","Single cross-reference to a foreign jurisdiction's regulatory instrument"],"plain_english_summary":"This directive mandates inspections and repairs for fatigue cracks in the aft pressure bulkhead web (the rear cabin pressure wall) on most Boeing 747 models, to prevent rapid decompression, tail over‑pressurisation, or loss of control. Owners/operators must follow FAA AD 2009‑04‑06 and Boeing service bulletin 747‑53A2482 for required inspections and fixes; 747‑400 LCF‑converted freighters are excluded. Amendment 2 corrects two errors to align with the FAA's revised AD."}},"importantCases":[],"_links":{"self":"/api/acts/ad-b747-314-amdt-2-aft-pressure-bulkhead-web","history":"/api/acts/ad-b747-314-amdt-2-aft-pressure-bulkhead-web/history","analysis":"/api/acts/ad-b747-314-amdt-2-aft-pressure-bulkhead-web/analysis","conflicts":"/api/acts/ad-b747-314-amdt-2-aft-pressure-bulkhead-web/conflicts","importantCases":"/api/acts/ad-b747-314-amdt-2-aft-pressure-bulkhead-web/important-cases","documents":"/api/acts/ad-b747-314-amdt-2-aft-pressure-bulkhead-web/documents"}}