{"id":"F2006B03056","name":"AD/B747/154 Amdt 1 - Nacelle Strut and Wing Structure - Rolls Royce RB211 Series Engine","slug":"ad-b747-154-amdt-1-nacelle-strut-and-wing-structure-rolls-royce-rb211-series-engine","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":42415,"registerId":"commonwealth-F2006B03056-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/B747/154 Amdt 1 - Nacelle Strut and Wing Structure - Rolls Royce RB211 Series Engine","content":"COMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 \\- 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n![](image.001.png)  \nBoeing 747 Series Aeroplanes\n\nAD/B747/154\n\nAmdt 1\n\n  \n\nNacelle Strut and Wing Structure \\- Rolls Royce RB211 Series Engine\n\n  \n2/96\n\nApplicability: Model 747 series aircraft with line positions 292 through 1033, equipped with Rolls Royce RB211 series engine.\n\nRequirement: Action in accordance with the technical requirements of FAA AD 95-13-05 Amdt 39- 9285.\n\nNote: Boeing Alert Service Bulletin 747-54A2157 Revision 1 refers.\n\nCompliance: As specified in the Requirement Document.\n\nThe Compliance of the initial issue of this Directive remains unchanged. This Amendment is effective from 1 February 1996.\n\nBackground: The FAA requires the incorporation of a modification of the strut and wing structure that has been developed by the manufacturer to improve the damage tolerance capability and durability of the strut-to-wing attachments, and reduce reliance on inspections of those attachments. Amendment 1 is issued to introduce a revision of the manufacturer's service bulletin which is related to this Directive.","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This amendment maintains identical scope to the original 1996 directive. It is purely a technical update to reference a revised manufacturer service bulletin. The applicability (which aircraft), the safety objective (structural modification), and compliance timing remain unchanged."},"complexity_factors":["Short, single-purpose directive (approximately 150 words)","Only 1 defined applicability criterion (line positions 292-1033)","Heavy reliance on external documents — compliance requires cross-referencing to FAA AD 95-13-05 and Boeing Service Bulletin 747-54A2157 Rev 1, which are not reproduced in the text","Minimal conditional logic — straightforward applicability test (model + engine type + line number range)","No nested exceptions or elaborate compliance timelines — 'as specified in the Requirement Document' defers entirely to external FAA directive"],"plain_english_summary":"This CASA Airworthiness Directive requires owners/operators of Boeing 747 production line numbers 292–1033 fitted with Rolls Royce RB211 engines to carry out a manufacturer-prescribed structural modification to the nacelle strut-to-wing attachments to address durability and damage-tolerance concerns. Amendment 1 does not change the safety requirement — it only references Boeing’s revised service bulletin (Revision 1) and directs compliance with FAA AD 95-13-05; the original compliance deadline remains unchanged."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The amendment does not change the Directive's operational scope. It introduces a revision of the manufacturer's service bulletin (Background: \"Amendment 1 is issued to introduce a revision of the manufacturer's service bulletin\") but explicitly states that \"The Compliance of the initial issue of this Directive remains unchanged.\" Applicability (affected line positions and engine type) and the requirement to comply with FAA AD 95-13-05 remain the same."},"complexity_factors":["Cross-reference to an external FAA airworthiness directive (Requirement: \"Action in accordance with the technical requirements of FAA AD 95-13-05\") increases reliance on a non‑local normative document.","Reference to a manufacturer's/Boeing service bulletin revision (Note: \"Boeing Alert Service Bulletin 747-54A2157 Revision 1\") requires operators to consult and apply technical supplier material.","Narrow fleet applicability specified by line positions (Applicability: \"line positions 292 through 1033\") requires fleet‑specific identification and record checks.","Technical nature of the mandated modification (Background: \"modification of the strut and wing structure... to improve the damage tolerance capability and durability\") implies specialised maintenance work and parts.","Compliance timing and procedures are entirely set by the referenced Requirement Document (Compliance: \"As specified in the Requirement Document\"), reducing local regulatory detail but adding dependency on that document for operational planning.","Operator cost and operational disruption are implicit (operators must implement the modification per Requirement), creating a direct compliance burden even though no monetary figures are provided."],"plain_english_summary":"This airworthiness directive requires certain Boeing 747s (line positions 292–1033) fitted with Rolls Royce RB211 engines to incorporate a manufacturer-designed modification to the nacelle strut-to-wing attachments by following FAA AD 95-13-05 and the related Boeing service bulletin. It affects aircraft operators, who must implement and pay for the modification. The stated purpose is to improve damage tolerance and durability of the attachments and to reduce reliance on repeated inspections."}},"importantCases":[],"_links":{"self":"/api/acts/ad-b747-154-amdt-1-nacelle-strut-and-wing-structure-rolls-royce-rb211-series-engine","history":"/api/acts/ad-b747-154-amdt-1-nacelle-strut-and-wing-structure-rolls-royce-rb211-series-engine/history","analysis":"/api/acts/ad-b747-154-amdt-1-nacelle-strut-and-wing-structure-rolls-royce-rb211-series-engine/analysis","conflicts":"/api/acts/ad-b747-154-amdt-1-nacelle-strut-and-wing-structure-rolls-royce-rb211-series-engine/conflicts","importantCases":"/api/acts/ad-b747-154-amdt-1-nacelle-strut-and-wing-structure-rolls-royce-rb211-series-engine/important-cases","documents":"/api/acts/ad-b747-154-amdt-1-nacelle-strut-and-wing-structure-rolls-royce-rb211-series-engine/documents"}}