{"id":"F2006B03054","name":"AD/B747/152 - Wings - Front Spar Web Between FSS 628.0 and 675.0","slug":"ad-b747-152-wings-front-spar-web-between-fss-628-0-and-675-0","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":42413,"registerId":"commonwealth-F2006B03054-current","compilationNumber":null,"startDate":"2026-04-01","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/B747/152 - Wings - Front Spar Web Between FSS 628.0 and 675.0","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\n# AD/B747/152 Wings - Front Spar Web Between FSS 628.0 and 675.0\n\nApplicability: B747SP aircraft, Variable Numbers RG001 to RG142 and RG171 to RG222, inclusive.\n\n# 8/95\n\n \n\nRequirement:  Perform an ultrasonic, detailed visual and high frequency eddy current inspection of the wing front spar web between wing front spar stations 628 and 675 in accordance with Boeing Service Bulletin (SB) 747-57A2259, Revision 2.\n\n \n\nNote: FAA AD 90-17-18 refers.\n\n \n\nCompliance: Initially inspect before further flight after 20 July 1995. Repeat the inspections at intervals not to exceed 1000 flights.\n\n \n\nModification in accordance with Boeing SB 747-57A2259, Revision 2, cancels the inspection requirement of this AD.\n\n \n\nBackground: An operator discovered a 790 mm crack in the front spar web of a 747SP aircraft when the aircraft was being refuelled. The fuel was leaking onto the No 3 engine. An undetected crack could lead to structural degradation, a fuel leak and fire.\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, targeted safety directive addressing a specific structural defect in a specific aircraft model. It has not expanded beyond its original purpose of mandating inspections for the identified crack risk."},"complexity_factors":["Single, specific technical requirement with clear reference to external Boeing Service Bulletin","Only one defined applicability criterion (aircraft serial numbers)","Simple compliance structure: initial inspection + recurring interval with cancellation condition","No nested exceptions or conditional logic","Short document (approximately 200 words of substantive content)","Single cross-reference to FAA AD 90-17-18 for context only"],"plain_english_summary":"This CASA Airworthiness Directive orders mandatory inspections of the wing front-spar web on specified Boeing 747SPs (serials RG001–RG142, RG171–RG222) using ultrasonic, detailed visual and high-frequency eddy-current methods. It was issued after discovery of a long crack that could allow fuel to leak onto an engine, creating a fire risk. Affected aircraft must be inspected before further flight (post‑20 July 1995) and every 1,000 flights thereafter unless modified per Boeing Service Bulletin 747‑57A2259 Rev 2."},"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":false,"description":"There is no indication within the AD text that the scope has been altered from its original framing: it targets a specific subset of B747SP aircraft by variable number (Applicability) and mandates inspections of the front spar web between FSS 628.0 and 675.0 (Requirement) until the Boeing Service Bulletin modification is installed (Modification). Operators of the listed aircraft bear the cost and operational burden of inspections (Compliance). The AD prescribes methods and intervals, leaving little discretionary latitude beyond choosing whether to perform the cancelling modification; the background (Background) explains the safety incident that prompted the measure."},"complexity_factors":["Technical inspection methods specified (ultrasonic, detailed visual, high‑frequency eddy current) require specialist non‑destructive testing equipment and trained technicians (Requirement).","Recurring interval (every ≤1,000 flights) creates ongoing operational scheduling and cost burdens for operators (Compliance).","Narrow applicability to defined variable numbers (RG001–RG142 and RG171–RG222) reduces administrative scope but requires accurate fleet identification (Applicability).","Compliance can be permanently ended by performing the Boeing SB modification, creating a clear trade‑off between one‑off modification cost and recurring inspection costs (Modification).","Procedural dependency on an external document (Boeing SB 747‑57A2259 Rev 2) means operators must follow manufacturer material not fully reproduced in the AD (Requirement).","Historical deadline language (inspect before further flight after 20 July 1995) and cross‑reference to FAA AD 90‑17‑18 create legacy timing and coordination considerations (Compliance; Note)."],"plain_english_summary":"This Airworthiness Directive requires operators of specified Boeing 747SP aircraft to inspect the wing front spar web between FSS 628.0 and 675.0 using ultrasonic, detailed visual and high‑frequency eddy‑current methods per Boeing Service Bulletin 747‑57A2259 Revision 2. Inspections must be done before further flight after 20 July 1995 and repeated at intervals not exceeding 1,000 flights; completing the Boeing SB modification cancels the inspection requirement. The AD responds to a discovered 790 mm crack that risked structural degradation, fuel leakage and fire."}},"importantCases":[],"_links":{"self":"/api/acts/ad-b747-152-wings-front-spar-web-between-fss-628-0-and-675-0","history":"/api/acts/ad-b747-152-wings-front-spar-web-between-fss-628-0-and-675-0/history","analysis":"/api/acts/ad-b747-152-wings-front-spar-web-between-fss-628-0-and-675-0/analysis","conflicts":"/api/acts/ad-b747-152-wings-front-spar-web-between-fss-628-0-and-675-0/conflicts","importantCases":"/api/acts/ad-b747-152-wings-front-spar-web-between-fss-628-0-and-675-0/important-cases","documents":"/api/acts/ad-b747-152-wings-front-spar-web-between-fss-628-0-and-675-0/documents"}}