{"id":"F2006B08470","name":"AD/CF6/27 - High Pressure Turbine Thermal Shield Inspection","slug":"ad-cf6-27-high-pressure-turbine-thermal-shield-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":51130,"registerId":"commonwealth-F2006B08470-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/CF6/27 - High Pressure Turbine Thermal Shield 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/CF6/27 High Pressure Turbine Thermal Shield Inspection 12/93\n\nApplicability: CF6-45, -50, -80A and -80C2 series.\n\n \n\nRequirement: Action in accordance with the technical requirements of FAA AD 93-14-18.\n\n \n\nNote: General Electric Service Bulletins 72-1021,-596, and -565 refer.\n\n \n\nCompliance: As specified in the FAA AD with effectivity commencing 11 Nov 1993.\n\n \n\nBackground:  This directive is raised because of a HPT thermal shield separation. Such separations could result in uncontained failure.\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 standard airworthiness directive with narrow, specific scope targeting a known safety defect in particular engine models. It has not expanded beyond its original safety-critical purpose."},"complexity_factors":["Very short document (approximately 200 words)","Only 4 defined engine models in applicability section","Single requirement referencing external FAA directive rather than detailing technical steps internally","No nested conditional logic or exceptions","No cross-references to other Australian legislation or regulations beyond the enabling Civil Aviation Regulations 1998","Straightforward compliance date structure"],"plain_english_summary":"This is an **Airworthiness Directive (AD)** — essentially a mandatory safety order for aircraft. It requires owners and operators of specific General Electric jet engines (the CF6-45, -50, -80A, and -80C2 series) to inspect a particular part called the **High Pressure Turbine (HPT) Thermal Shield**.\n\n**Why it matters:** A thermal shield on one of these engines separated (broke off), which could lead to an \"uncontained failure\" — aviation speak for engine parts flying out and potentially damaging the aircraft or injuring people. The directive mandates inspections to catch this problem before it causes an accident.\n\n**What must be done:** Aircraft operators must follow the technical instructions in a US Federal Aviation Administration (FAA) directive (AD 93-14-18), starting from 11 November 1993. The directive references specific General Electric service bulletins that detail the inspection procedures."},"flash_summary":{"complexity_score":5,"scope_assessment":{"changed":false,"description":"The directive applies to the CF6-45, -50, -80A and -80C2 series and requires action in accordance with FAA AD 93-14-18, effective from 11 November 1993. The text does not indicate any change to the applicability or substantive scope from the original stated requirement; it adopts the FAA AD and references GE service bulletins for technical detail (Applicability; Requirement; Note; Compliance)."},"complexity_factors":["Cross-reference to an external FAA airworthiness directive (FAA AD 93-14-18) — implementers must obtain and follow that separate document (Requirement).","Multiple engine variants covered (CF6-45, -50, -80A, -80C2) creating fleet-level variation in applicability (Applicability).","Reference to several GE service bulletins (72-1021, 72-596, 72-565) for technical detail — requires operators to reconcile multiple technical documents (Note).","Technical nature of the inspection and potential corrective actions (high-pressure turbine thermal shield) implies specialised maintenance skills and possible engine removal/parts replacement (Background).","Operational scheduling and parts-supply implications (aircraft downtime, procurement of GE parts) increase implementation complexity (Compliance; Note)."],"plain_english_summary":"This directive mandates operators of GE CF6-45, -50, -80A and -80C2 engines to carry out the inspections and corrective actions set out in FAA AD 93-14-18 (with GE service bulletins as technical references) after an HPT thermal‑shield separation risk was identified. CASA enforces the requirement; operators and their maintenance organisations bear inspection, repair and downtime costs and must adjust maintenance scheduling and parts procurement to comply."}},"importantCases":[],"_links":{"self":"/api/acts/ad-cf6-27-high-pressure-turbine-thermal-shield-inspection","history":"/api/acts/ad-cf6-27-high-pressure-turbine-thermal-shield-inspection/history","analysis":"/api/acts/ad-cf6-27-high-pressure-turbine-thermal-shield-inspection/analysis","conflicts":"/api/acts/ad-cf6-27-high-pressure-turbine-thermal-shield-inspection/conflicts","importantCases":"/api/acts/ad-cf6-27-high-pressure-turbine-thermal-shield-inspection/important-cases","documents":"/api/acts/ad-cf6-27-high-pressure-turbine-thermal-shield-inspection/documents"}}