{"id":"F2007L02444","name":"AD/B737/141 Amdt 1 - Forward Pressure Bulkhead","slug":"ad-b737-141-amdt-1-forward-pressure-bulkhead","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":67901,"registerId":"commonwealth-F2007L02444-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Boeing 737 Series Aeroplanes","sectionType":"division","heading":"Boeing 737 Series Aeroplanes","content":"### Boeing 737 Series Aeroplanes\n\n| AD/B737/141 Amdt 1 | Forward Pressure Bulkhead | 9/2007 |\n| ------------------ | ------------------------- | ------ |\n\n| Applicability: | Model 737-100, -200, -300, -400, and -500 series aircraft, with line numbers 1 through 2737.                                                                                                                                                                                                                                                                                              |\n| -------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | Action in accordance with the technical requirements of FAA AD 2000-05-29 Amdt 39-11639.Note: Boeing Alert Service Bulletin (ASB) 737-53A1173 Revision 4, or later FAA approved revision, refers.                                                                                                                                                                                         |\n| Compliance:    | As specified in the Requirement document, with a revised effective date of15 June 2000.The compliance time remains unchanged by this issue of the Directive.                                                                                                                                                                                                                              |\n|                | This Amendment becomes effective on 30 August 2007.                                                                                                                                                                                                                                                                                                                                       |\n| Background:    | The FAA received reports of numerous fatigue cracks found on critical areas of the forward pressure bulkhead. The actions specified by this Directive are intended to prevent such cracking, which could result in rapid decompression of the fuselage.Amendment 1 is issued to amend the Requirement note to list the latest Boeing Alert Service Bulletin related to FAA AD 2000-05-29. |\n\n![](image.001.png)  \nDavid Villiers  \nDelegate of the Civil Aviation Safety Authority\n\n20 July 2007","sortOrder":0},{"sectionNumber":"AD/B737/141 Amdt 1","sectionType":"part","heading":"AD/B737/141 Amdt 1","content":"## AD/B737/141 Amdt 1","sortOrder":1},{"sectionNumber":"Forward Pressure Bulkhead","sectionType":"part","heading":"Forward Pressure Bulkhead","content":"## Forward Pressure Bulkhead","sortOrder":2},{"sectionNumber":"9/2007","sectionType":"part","heading":"9/2007","content":"## 9/2007","sortOrder":3}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This amendment maintains the original scope precisely. It is a technical update that changes only the reference to the Boeing service bulletin revision number (updating to Revision 4). The applicability (which aircraft), the safety problem addressed (fatigue cracks in forward pressure bulkhead), and the compliance requirements all remain identical to the original 2000 directive."},"complexity_factors":["Very short document (approximately 250 words)","Only 2 substantive operative provisions: applicability and requirement","Single cross-reference to external FAA directive and Boeing service bulletin (no internal cross-referencing)","No defined terms section — uses plain technical language","Simple amendment structure: updates a reference note without changing substantive compliance obligations","No conditional logic, exceptions, or nested provisions"],"plain_english_summary":"This Airworthiness Directive requires operators of older Boeing 737-100 to -500 series (line numbers 1–2737) to inspect and repair the forward pressure bulkhead after FAA findings of fatigue cracks that could cause rapid decompression. Compliance must follow FAA AD 2000-05-29 and Boeing Alert Service Bulletin 737-53A1173 (Revision 4 or later). Amendment 1 only updates the Boeing service bulletin reference; the original safety requirements and deadlines remain unchanged."},"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":false,"description":"Amendment 1 only updates the Requirement note to list the latest Boeing Alert Service Bulletin related to FAA AD 2000-05-29 and does not alter applicability or compliance times. The directive states that 'The compliance time remains unchanged by this issue of the Directive' and that Amendment 1 'is issued to amend the Requirement note to list the latest Boeing Alert Service Bulletin' (Requirement; Compliance; Background)."},"complexity_factors":["Cross-reference to an external FAA AD (FAA AD 2000-05-29) creates dependency on another regulator's technical requirement (Requirement).","Dependence on Boeing Alert Service Bulletin 737-53A1173 Revision 4, or later FAA-approved revision, means compliance may change with later approved revisions (Requirement).","Applicability is limited by specific models and line numbers (Model 737-100, -200, -300, -400, -500; line numbers 1–2737), requiring fleet-specific applicability checks (Applicability).","The Directive amends the Requirement note only; it does not change compliance times, but retains a revised effective date of 15 June 2000 while the amendment becomes effective 30 August 2007, creating potential administrative tracking issues (Compliance).","Safety risk described (fatigue cracking that could cause rapid decompression) increases operational urgency and inspection frequency for affected operators (Background).","Operational and financial burden falls on aircraft operators to perform inspections, repairs or modifications per the referenced documents (Requirement; Background).","Need to track FAA approvals for future ASB revisions imposes ongoing regulatory-document management for operators and maintenance organisations (Requirement)."],"plain_english_summary":"This Directive requires operators of Boeing 737-100/-200/-300/-400/-500 (line numbers 1–2737) to carry out inspections and corrective work on the forward pressure bulkhead in line with FAA AD 2000-05-29 and Boeing Alert Service Bulletin 737-53A1173 Revision 4 (or a later FAA‑approved revision). It updates the referenced service bulletin but does not change who must comply or the compliance times. The requirement responds to reported fatigue cracks that could cause rapid decompression and shifts inspection/repair costs to aircraft operators."}},"importantCases":[],"_links":{"self":"/api/acts/ad-b737-141-amdt-1-forward-pressure-bulkhead","history":"/api/acts/ad-b737-141-amdt-1-forward-pressure-bulkhead/history","analysis":"/api/acts/ad-b737-141-amdt-1-forward-pressure-bulkhead/analysis","conflicts":"/api/acts/ad-b737-141-amdt-1-forward-pressure-bulkhead/conflicts","importantCases":"/api/acts/ad-b737-141-amdt-1-forward-pressure-bulkhead/important-cases","documents":"/api/acts/ad-b737-141-amdt-1-forward-pressure-bulkhead/documents"}}