{"id":"F2006B08469","name":"AD/CF6/26 - Stage 11 to 13 Compressor Spool Inspection","slug":"ad-cf6-26-stage-11-to-13-compressor-spool-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":51127,"registerId":"commonwealth-F2006B08469-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/CF6/26 - Stage 11 to 13 Compressor Spool Inspection","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 - 106 CIVIL AVIATION SAFETY AUTHORITY\n\nSCHEDULE OF AIRWORTHINESS DIRECTIVES\n\n \n\n![](image.001.png)  General Electric Turbine Engines - CF6 Series\n\n \n\nAD/CF6/26 Stage 11 to 13 Compressor Spool Inspection 12/93\n\nApplicability: CF6-45/-50 series.\n\n \n\nRequirement: Action in accordance with the technical requirements of FAA AD 93-13-10.\n\n \n\nNote: GE Service Bulletin No 72-1006 Revision 1 dated 14 November 1991 refers.\n\nCompliance: As specified in the FAA AD with effectivity commencing 11 November 1993. Background:               There have been reports of fatigue cracking in the 12th stage compressor disc.\n\nConsequently, there is need for a one time inspection for cracking and measurement\n\nof the stage 12 compressor disc web-to-rim transition area of the stage 11-13 compressor spool. Depending on the results, the items are then to be replaced, reidentified and relifed.\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, targeted safety directive addressing a specific known defect in a specific engine model. It has not expanded beyond its original purpose of mandating inspection for fatigue cracking in the stage 12 compressor disc."},"complexity_factors":["Very short document (approximately 150 words of substantive content)","Only 1 defined applicability criterion (CF6-45/-50 series engines)","Single requirement referencing external technical document (FAA AD 93-13-10) rather than spelling out detailed procedures","No nested exceptions or conditional logic — straightforward one-time inspection requirement","No cross-references to other Australian legislation beyond Civil Aviation Regulations 1998 Part 39","Technical content is delegated to external aerospace engineering standards"],"plain_english_summary":"This CASA Airworthiness Directive mandates a one‑time inspection and measurement of the stage 11–13 compressor spool (specifically the 12th‑stage compressor disc transition area) on GE CF6‑45 and CF6‑50 engines after fatigue cracking was found. It affects airlines, operators and maintenance organisations using these engines and aims to prevent catastrophic engine failure by requiring repair, replacement, or life‑limit actions as indicated."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The instrument implements a one‑time inspection for CF6‑45 and CF6‑50 engines as set out in the text and by reference to FAA AD 93‑13‑10. There is no text indicating an expansion or narrowing of scope beyond that stated applicability and the referenced FAA and GE documents."},"complexity_factors":["Requires technical non‑destructive inspection and measurement of a specific disc area (stage 12 web‑to‑rim transition).","Directs compliance by reference to an external instrument (FAA AD 93‑13‑10), creating dependency on another document for procedural details.","Potential follow‑on actions (replacement, reidentification, re‑lifeing) introduce conditional administrative and logistical steps.","Narrow applicability (CF6‑45/‑50) reduces scope but concentrates impact on affected operators and parts supply.","One‑time requirement lowers ongoing compliance complexity, but single inspections can create scheduling and downtime pressures."],"plain_english_summary":"This Airworthiness Directive requires a one‑time inspection of the stage 11–13 compressor spool on General Electric CF6‑45 and CF6‑50 engines to detect fatigue cracking and measure the stage‑12 disc web‑to‑rim transition. It directs compliance with FAA AD 93‑13‑10 and references GE Service Bulletin 72‑1006 Rev 1.\n\nOperators and maintenance organisations must perform the inspection, bear downtime and replacement costs, and reidentify or relife parts if defects are found; compliance commenced 11 November 1993."}},"importantCases":[],"_links":{"self":"/api/acts/ad-cf6-26-stage-11-to-13-compressor-spool-inspection","history":"/api/acts/ad-cf6-26-stage-11-to-13-compressor-spool-inspection/history","analysis":"/api/acts/ad-cf6-26-stage-11-to-13-compressor-spool-inspection/analysis","conflicts":"/api/acts/ad-cf6-26-stage-11-to-13-compressor-spool-inspection/conflicts","importantCases":"/api/acts/ad-cf6-26-stage-11-to-13-compressor-spool-inspection/important-cases","documents":"/api/acts/ad-cf6-26-stage-11-to-13-compressor-spool-inspection/documents"}}