{"id":"F2006B03239","name":"AD/B747/59 - Fuselage Upper Body Tear Strap Disbonding","slug":"ad-b747-59-fuselage-upper-body-tear-strap-disbonding","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":42663,"registerId":"commonwealth-F2006B03239-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/B747/59 - Fuselage Upper Body Tear Strap Disbonding","content":"---\nmeta-content-style-type: text/css\nmeta-content-type: application/xhtml+xml; charset=utf-8\nmeta-generator: Aspose.Words for .NET 22.10.0\n---\n\n?xml version=\"1.0\" encoding=\"utf-8\" standalone=\"no\"?>\n\nCOMMONWEALTH OF AUSTRALIA (Civil Aviation Regulations 1998), PART 39 - 105 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n \n\n![](image.001.png)  Boeing 747 Series Aeroplanes\n\n \n\nAD/B747/59 Fuselage Upper Body Tear Strap Disbonding 11/87\n\nApplicability: All models listed in the Requirement Document. Requirement: Action in accordance with Boeing SB 747-53A2279 R1.\n\nNote: FAA AD 87-16-13 refers.\n\n \n\nCompliance: Inspect in accordance with the Requirement Document until terminating action carried out.\n\n \n\nBackground: Disbonding of the upper body hot bonded skin tear straps has been reported.\n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n\n \n","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This is a discrete, single-issue airworthiness directive from 1987 addressing a specific structural defect in Boeing 747 aircraft. It has not expanded beyond its original purpose of mandating inspections for upper body tear strap disbonding."},"complexity_factors":["Extremely short document (under 200 words)","No defined terms section — relies entirely on external Boeing Service Bulletin for technical details","Single, straightforward compliance requirement (inspect until fixed)","No nested exceptions, conditional logic, or cross-referencing within the instrument itself","References only one external document (Boeing SB 747-53A2279 R1) and one FAA AD for correlation"],"plain_english_summary":"**What this is:** An Airworthiness Directive (AD) — essentially a mandatory safety notice issued by Australia's Civil Aviation Safety Authority (CASA) that requires owners or operators of specific aircraft to take corrective action.\n\n**What it does:** This directive orders inspections of Boeing 747 aircraft to check for a specific structural problem: the \"disbonding\" (separation or peeling apart) of tear straps in the upper fuselage. Tear straps are reinforced strips bonded to the aircraft's skin that help stop cracks from spreading — critical for maintaining cabin pressure and structural integrity.\n\n**Who it affects:** Anyone who owns, operates, or maintains Boeing 747 series aircraft in Australia.\n\n**What must be done:** Operators must follow the inspection procedures outlined in Boeing Service Bulletin 747-53A2279 Revision 1. These inspections must continue until a permanent fix (\"terminating action\") is completed.\n\n**Why it matters:** Disbonded tear straps compromise the aircraft's ability to contain pressurisation and resist structural failure. This is a safety-of-flight issue — if the straps separate, a small crack could grow rapidly, potentially leading to catastrophic decompression or loss of the aircraft."},"flash_summary":{"complexity_score":5,"scope_assessment":{"changed":false,"description":"The directive is limited to models listed in the Requirement Document and requires inspections to address reported disbonding of the upper body tear straps. The text provides no indication that the scope has been expanded or narrowed from its stated purpose; it consistently ties applicability and required actions to the Requirement Document and Boeing service bulletin (Applicability; Requirement; Compliance; Background)."},"complexity_factors":["References external documents for technical detail (Boeing SB 747-53A2279 R1 and an unspecified Requirement Document), creating dependency on those texts for full implementation (Requirement; Compliance).","Applicability is tied to ‘‘all models listed in the Requirement Document’’ rather than enumerating models in the directive, requiring users to consult the Requirement Document to determine whether an aircraft is affected (Applicability).","Terminating action is not specified in the AD itself; compliance is required ‘‘until terminating action carried out,’’ causing ongoing obligations and uncertainty until that action is identified and completed (Compliance).","Minimal procedural detail in the AD (no intervals, methods, authorised personnel, or record-keeping described), pushing operational specifics to the referenced service bulletin and Requirement Document (Requirement; Compliance).","Cross-reference to a foreign regulator (FAA AD 87-16-13) implies potential alignment but requires parallel checks against that AD for full context (Note)."],"plain_english_summary":"This airworthiness directive requires operators of the listed Boeing 747 models to carry out recurring inspections of the upper-body hot-bonded skin tear straps in accordance with Boeing Service Bulletin 747-53A2279 Revision 1 and the Requirement Document, prompted by reported disbonding.  \n\nInspections must continue until the terminating action in the referenced documents is completed; operators bear the compliance costs. The AD cross-references a related FAA directive."}},"importantCases":[],"_links":{"self":"/api/acts/ad-b747-59-fuselage-upper-body-tear-strap-disbonding","history":"/api/acts/ad-b747-59-fuselage-upper-body-tear-strap-disbonding/history","analysis":"/api/acts/ad-b747-59-fuselage-upper-body-tear-strap-disbonding/analysis","conflicts":"/api/acts/ad-b747-59-fuselage-upper-body-tear-strap-disbonding/conflicts","importantCases":"/api/acts/ad-b747-59-fuselage-upper-body-tear-strap-disbonding/important-cases","documents":"/api/acts/ad-b747-59-fuselage-upper-body-tear-strap-disbonding/documents"}}