{"id":"F2006B08473","name":"AD/CF6/30 - CF6-80A Stage 1 High Pressure Turbine Disc Inspection","slug":"ad-cf6-30-cf6-80a-stage-1-high-pressure-turbine-disc-inspection","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":51138,"registerId":"commonwealth-F2006B08473-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"1","sectionType":"section","heading":"AD/CF6/30 - CF6-80A Stage 1 High Pressure Turbine Disc 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\n# AD/CF6/30 CF6-80A Stage 1 High Pressure Turbine Disc Inspection\n\nApplicability: CF6-80A series engines.\n\n \n\nRequirement: Action in accordance with the technical requirements of FAA AD 94-07-04.\n\n \n\nNote: General Electric Service Bulletin No 72-604 revision 3 refers.\n\n \n\nCompliance: As specified in the FAA AD with an effective date of 18 August 1994.\n\n# 9/94\n\n \n\nBackground:  This directive requires an inspection for cracks in the stage 1 high pressure turbine disc rim bolt holes and replacement as necessary with serviceable parts. It originates from an uncontained stage 1 high pressure turbine 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","sortOrder":0}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This Airworthiness Directive maintains its original narrow scope — addressing a specific safety defect in a specific engine model. It has not expanded beyond its original purpose of mandating inspections following a known failure event."},"complexity_factors":["Very short document (approximately 150 words of substantive content)","Only 1 defined term implicitly referenced (FAA AD 94-07-04)","No nested conditional logic or exceptions","Single straightforward requirement: inspect and replace if necessary","Compliance delegated entirely to external FAA document (incorporation by reference)","No cross-references to other Australian legislation beyond Civil Aviation Regulations 1998 Part 39"],"plain_english_summary":"This is an **Airworthiness Directive** (a mandatory safety order) issued by Australia's Civil Aviation Safety Authority for a specific type of aircraft engine.\n\n**What it does:**\n- Requires airlines and aircraft operators to inspect a critical part of General Electric CF6-80A jet engines — specifically the **stage 1 high pressure turbine disc** (a spinning component that extracts energy from hot gases to power the engine)\n- Operators must check for **cracks in the bolt holes around the rim** of this disc\n- If cracks are found, the damaged disc must be replaced with a serviceable (safe, working) part\n\n**Who it affects:**\n- Airlines and operators using aircraft with **CF6-80A series engines** (commonly used on Boeing 767 and Airbus A300 aircraft)\n- Maintenance engineers responsible for engine overhauls\n\n**Why it matters:**\n- This directive was triggered by an **uncontained engine failure** — meaning a turbine disc broke apart and pieces escaped the engine casing, which can damage the aircraft and endanger passengers\n- The bolt hole cracks can grow and cause the disc to fracture during flight, potentially leading to catastrophic engine failure\n- Compliance is **mandatory** and follows a US Federal Aviation Administration (FAA) directive dated 18 August 1994\n\n**Key point:** This is a **safety-critical maintenance requirement** — operators cannot legally fly these engines without completing these inspections."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The instrument adopts and requires compliance with FAA AD 94-07-04 for CF6-80A engines and specifies the same inspection and replacement scope described in the directive. Nothing in the text expands or narrows the technical target beyond the stage 1 high pressure turbine disc rim bolt hole inspections and replacement as necessary; it therefore does not change the scope from the stated technical requirement. (\"Requirement\"; \"Applicability\"; \"Background\")"},"complexity_factors":["Cross-reference to an external FAA Airworthiness Directive for the substantive technical and compliance details (Requirement; Compliance)","Reference to an external manufacturer service bulletin for technical procedures (Note)","Technical nature of the inspection (crack detection on stage 1 HPT disc rim bolt holes) requiring specialised maintenance capability (Background)","Potential need for part replacement and attendant logistics (Background)","Narrow, engine-series-specific applicability reduces breadth but increases technical specificity (Applicability)"],"plain_english_summary":"# What this instrument does\n\n- Mechanically, the directive requires operators of General Electric CF6-80A series engines to carry out the inspection and remedial work set out in FAA Airworthiness Directive (AD) 94-07-04. (\"Applicability\"; \"Requirement\"; \"Compliance\")\n\n- The inspection specifically targets cracks in the stage 1 high pressure turbine (HPT) disc rim bolt holes; any cracked parts must be removed and replaced with serviceable parts. (\"Background\")\n\n- The directive points users to General Electric Service Bulletin No. 72-604 revision 3 for related technical detail. (\"Note\")\n\n# Who this affects and who decides\n\n- Aircraft and engine owners/operators that use CF6-80A series engines must carry out the inspection and any required replacements. (\"Applicability\"; \"Requirement\")\n\n- The Civil Aviation Safety Authority gives effect to the requirement by adopting the FAA AD; the AD to be followed is specified with an effective date of 18 August 1994. (\"Requirement\"; \"Compliance\")\n\n# Why it matters (source's stated purpose and the practical mechanics)\n\n- The source states the action responds to an uncontained stage 1 HPT failure and requires inspection and replacement to address cracks in the stage 1 HPT disc rim bolt holes. That is the stated safety trigger and the remedial mechanism. (\"Background\")\n\n# Cost, incentives, and compliance mechanics (what changes about behaviour and who pays)\n\n- Who pays: the direct costs of performing inspections and any required part replacements will fall to the engine/aircraft operators and their maintenance providers because operators must implement the FAA AD requirements as adopted here. (\"Requirement\"; \"Compliance\")\n\n- Behavioural change required: operators must schedule and perform the specified inspections on applicable engines and remove/replace any cracked components with serviceable parts. Those actions change maintenance scheduling and may impose additional parts and labour costs. (\"Background\"; \"Requirement\")\n\n- Incentives: the directive creates a compliance incentive—adhere to the FAA AD to meet the CASA mandate—by making the FAA AD the standard to follow. This channels operator decisions toward the inspection and replacement steps defined in the FAA AD. (\"Requirement\")\n\n# Implementation, discretion and information dependencies\n\n- Discretion: the directive itself does not grant local discretion to substitute alternative inspection regimes; it requires action in accordance with the FAA AD as adopted. Any variation from those technical requirements would depend on separate regulatory approval processes not described here. (\"Requirement\"; \"Compliance\")\n\n- Information dependencies and implementation risk: the directive cross-references FAA AD 94-07-04 and GE Service Bulletin No. 72-604 rev 3 for the technical content. Effective implementation depends on access to and interpretation of those external technical documents. (\"Requirement\"; \"Note\")\n\n# Trade-offs and practical effects to note\n\n- The directive replaces a maintenance-as-usual decision with a mandated inspection/remediation sequence for the specified engine family. That shifts costs and scheduling responsibility onto operators for the engines in scope. (\"Applicability\"; \"Requirement\"; \"Compliance\")\n\n- The action is narrowly defined by engine type (CF6-80A) and by the technical target (stage 1 HPT disc rim bolt holes), so it does not broaden maintenance obligations beyond that specified scope. (\"Applicability\"; \"Background\")\n\n# Source citations\n\n- Applicability: \"CF6-80A series engines.\" (Applicability)\n- Requirement: \"Action in accordance with the technical requirements of FAA AD 94-07-04.\" (Requirement)\n- Compliance: \"As specified in the FAA AD with an effective date of 18 August 1994.\" (Compliance)\n- Technical reference: \"General Electric Service Bulletin No 72-604 revision 3 refers.\" (Note)\n- Background/rationale: \"requires an inspection for cracks in the stage 1 high pressure turbine disc rim bolt holes and replacement as necessary with serviceable parts. It originates from an uncontained stage 1 high pressure turbine failure.\" (Background)\n"}},"importantCases":[],"_links":{"self":"/api/acts/ad-cf6-30-cf6-80a-stage-1-high-pressure-turbine-disc-inspection","history":"/api/acts/ad-cf6-30-cf6-80a-stage-1-high-pressure-turbine-disc-inspection/history","analysis":"/api/acts/ad-cf6-30-cf6-80a-stage-1-high-pressure-turbine-disc-inspection/analysis","conflicts":"/api/acts/ad-cf6-30-cf6-80a-stage-1-high-pressure-turbine-disc-inspection/conflicts","importantCases":"/api/acts/ad-cf6-30-cf6-80a-stage-1-high-pressure-turbine-disc-inspection/important-cases","documents":"/api/acts/ad-cf6-30-cf6-80a-stage-1-high-pressure-turbine-disc-inspection/documents"}}