{"id":"F2006B08486","name":"AD/CF6/48 Amdt 1 - Nozzle Guide Vanes","slug":"ad-cf6-48-amdt-1-nozzle-guide-vanes","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":51172,"registerId":"commonwealth-F2006B08486-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"Requirement: 1. NGVs Previously Inspecte","sectionType":"part","heading":"Requirement: 1. NGVs Previously Inspected by Flex Borescope before the effective date of this Directive:","content":"# Requirement: 1. NGVs Previously Inspected by Flex Borescope before the effective date of this Directive:\n\nReinspect or remove from service the NGVs.","sortOrder":0},{"sectionNumber":"2. NGVs Not Previously Inspected by Flex","sectionType":"part","heading":"2. NGVs Not Previously Inspected by Flex Borescope:","content":"# 2. NGVs Not Previously Inspected by Flex Borescope:\n\nRemove from service, or re-inspect using the Accomplishment Instructions of GE SB No. CF6-80E1 S/B 72-0217, Revision 2, dated 5 January 5 2004.\n\nNote 3: FAA AD 2004-09-34 Amdt 39-13625 refers.\n\nCompliance: For Requirement 1: Unless previously accomplished in accordance with the Conditions and Reinspection intervals listed in the \"Inspection Table for Cracking in the Airfoil Outer Fillet,\" Figure 5, of GE Service Bulletin (SB) No. CF6-80E1 S/B 72-0217, Revision 2, or within 200 cycles-in-service-since-last inspection (CSLI), whichever is earlier.\n\nFor Requirement 2: For NGVs with more than 800 cycles-since-overhaul (CSO) on the effective date of this AD, within 50 cycles-in-service (CIS) after the effective date of this AD; thereafter in accordance with the Conditions and Reinspection intervals listed in the \"Inspection Table for Cracking in the Airfoil Outer Fillet,\" Figure 5, of GE SB No. CF6-80E1 S/B 72-0217, Revision 2.","sortOrder":1},{"sectionNumber":"General Electric Turbine Engines - CF6 S","sectionType":"part","heading":"General Electric Turbine Engines - CF6 Series","content":"# General Electric Turbine Engines \\- CF6 Series\n\nAD/CF6/48 Amdt 1 (continued)\n\nFor NGVs with 800 or fewer CSO on the effective date of this AD, at the first regular HPT blade inspection after 800 CSO, but before reaching 900 CSO; thereafter in accordance with the Conditions and Reinspection intervals listed in the \"Inspection Table for Cracking in the Airfoil Outer Fillet,\" Figure 5, of GE SB No. CF6-80E1 S/B 72-0217, Revision 2.\n\nFor the purposes of this AD, cycles-since-overhaul (CSO) is defined as cycles since repair as described in GE SB No. CF6-80E1 S/B 72-0164 dated 16 March 1999.\n\nThe original issue of this Directive became effective on 20 February 2003\\. This Amendment becomes effective on 30 September 2004.\n\nBackground: An uncontained failure has been attributed to high-pressure turbine stage two nozzle guide vane distress. This directive introduced an inspection program to identify early signs of distress.\n\nThis amendment reduces the inspection interval, because it has been determined that the cracks that develop could grow at a faster rate than originally expected.\n\nThe original issue of this Directive became effective on 20 February 2003.\n\n![Signature of Gary J Carr Delegate of the Civil Aviation Safety Authority](image.002.jpeg)  \n\nGary J Carr\n\nDelegate of the Civil Aviation Safety Authority 13 August 2004\n\n![](image.001.png)  \n\nThe above AD is notified in the Commonwealth of Australia Gazette on 8 September 2004.","sortOrder":2}],"analysis":{"flash_summary":{"complexity_score":6,"scope_assessment":{"changed":true,"description":"The amendment shortens inspection intervals compared with the original directive and imposes earlier mandatory reinspection or removal for NGVs depending on prior inspection status and CSO thresholds. Mechanically, it tightens timing and expands near‑term compliance obligations rather than adding new engine models or airworthiness criteria."},"complexity_factors":["Multiple conditional paths: separate requirements for NGVs previously inspected by flex borescope versus not previously inspected.","Different timing rules tied to engine usage metrics (cycles‑since‑overhaul (CSO), cycles‑in‑service (CIS), cycles‑since‑last‑inspection (CSLI)) with distinct thresholds (50 CIS, 200 CSLI, 800 CSO, 900 CSO).","Dependence on external technical documents: GE SB No. CF6-80E1 S/B 72-0217 Rev 2 for inspection procedures and Figure 5 'Inspection Table for Cracking in the Airfoil Outer Fillet', and GE SB No. CF6-80E1 S/B 72-0164 for the CSO definition.","Choice between re‑inspection using specific accomplishment instructions or removal from service creates operational decision points for operators.","Cross-reference to FAA AD 2004-09-34 adds regulatory alignment considerations across jurisdictions.","Staggered compliance dates and an amendment effective date different from the original directive increase tracking and recordkeeping complexity for operators and maintainers.","Technical, inspection‑level requirements (flex borescope, crack‑growth assumptions) require specialist capability and may constrain which maintenance providers can comply."],"plain_english_summary":"This amendment requires operators of GE CF6-series engines to reinspect or remove from service certain high-pressure turbine stage two nozzle guide vanes (NGVs), using the inspection procedures in GE Service Bulletin CF6-80E1 S/B 72-0217 Rev 2. It ties compliance timing to cycles‑since‑overhaul and cycles‑in‑service thresholds. The amendment shortens inspection intervals because cracks were found to grow faster than initially expected. That requires more frequent inspection, increasing operator inspection and scheduling costs; the AD and the referenced service bulletin set the standards and deadlines."},"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"},"kimi_summary":{"content_quality":"ok","complexity_score":6,"scope_assessment":{"changed":false,"description":"This amendment stays within the original scope of AD/CF6/48. The original directive introduced an inspection program for CF6-80E1 NGVs following an uncontained failure. This amendment simply tightens the inspection intervals based on new technical data about crack propagation rates. It does not expand to new engine models, new component types, or new operational contexts beyond the original safety concern."},"complexity_factors":["Multiple compliance pathways depending on prior inspection history (Requirement 1 vs Requirement 2)","Nested timing calculations based on three different metrics: cycles-since-last-inspection (CSLI), cycles-since-overhaul (CSO), and cycles-in-service (CIS)","Cross-reference to external technical document (GE Service Bulletin CF6-80E1 S/B 72-0217, Revision 2) for inspection procedures and intervals","Threshold-based compliance triggers (800 CSO cutoff creates two distinct compliance regimes)","Definition of CSO requires reference to a second external document (GE SB No. CF6-80E1 S/B 72-0164 dated 16 March 1999)","Conditional logic: 'whichever is earlier' comparisons for compliance timing","Technical aviation terminology requiring specialised knowledge (NGVs, borescope, airfoil outer fillet, uncontained failure)","Amendment structure requires understanding of what changed from original AD/CF6/48 (effective 20 February 2003) versus this Amendment 1 (effective 30 September 2004)"],"plain_english_summary":"This CASA Airworthiness Directive requires operators of GE CF6-80E1 engines (notably on A330s) to inspect or remove certain high‑pressure turbine nozzle guide vanes because cracks have been found to grow faster than expected. It affects airlines and maintenance organisations, sets cycle‑based compliance deadlines and recurring inspections, and tightens the original 2003 requirements to reduce the risk of uncontained engine failure that could endanger aircraft and people."}},"importantCases":[],"_links":{"self":"/api/acts/ad-cf6-48-amdt-1-nozzle-guide-vanes","history":"/api/acts/ad-cf6-48-amdt-1-nozzle-guide-vanes/history","analysis":"/api/acts/ad-cf6-48-amdt-1-nozzle-guide-vanes/analysis","conflicts":"/api/acts/ad-cf6-48-amdt-1-nozzle-guide-vanes/conflicts","importantCases":"/api/acts/ad-cf6-48-amdt-1-nozzle-guide-vanes/important-cases","documents":"/api/acts/ad-cf6-48-amdt-1-nozzle-guide-vanes/documents"}}