{"id":"F2009L01970","name":"AD/CF6/76 - High Pressure Turbine Stage 1 Rotor Discs","slug":"ad-cf6-76-high-pressure-turbine-stage-1-rotor-discs","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":79162,"registerId":"commonwealth-F2009L01970-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"General Electric Turbine Engines - CF6 S","sectionType":"division","heading":"General Electric Turbine Engines - CF6 Series","content":"### General Electric Turbine Engines - CF6 Series\n\n| AD/CF6/76 | High Pressure Turbine Stage 1 Rotor Discs | 6/2009 |\n| --------- | ----------------------------------------- | ------ |\n\n| Applicability: | General Electric Company (GE) CF6-80A series turbofan engines with any of the following stage 1 high-pressure turbine (HPT) rotor disc part numbers (P/Ns), installed:(a) 1380M69G01; 1380M69G02; 1380M69G04; 1380M69G05; or 1380M69G06; or(b) 9234M67G12; 9234M67G13; 9234M67G14; 9234M67G15; or 9234M67G16; or(c) 9362M58G04; or(d) 9367M45G01; 9367M45G03; 9367M45G05; 9367M45G06; 9367M45G07; or 9367M45G08.Note 1: These CF6-80A series turbofan engines are installed on, but not limited to, Airbus A310-200 series and Boeing 767-200 and -300 series aeroplanes. |\n| -------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | 1. Remove from service HPT stage 1 rotor discs identified in the applicability section of this AD.2. Do not install any of the HPT stage 1 rotor discs, identified in the applicability section of this AD into any engine.Note 2: FAA AD 2009-08-06 Amdt 39-15879 dated 6 April 2009 refers.                                                                                                                                                                                                                                                                             |\n| Compliance:    | For Requirement 1 - Within 30 days after the effective date of this AD, unless the actions have already been done.For Requirement 2 - After the effective date of this AD.                                                                                                                                                                                                                                                                                                                                                                                                |\n|                | This Airworthiness Directive becomes effective on 4 June 2009.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |\n\n| Background: | The discs detailed in this AD are susceptible to cracks developing at the aft chamfer of the blade dovetail slots. The actions detailed in this AD are to prevent cracks developing at the aft chamfer of the blade dovetail slots that could propagate to a failure of the disc and cause an uncontained engine failure and damage to the aeroplane. |\n| ----------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n\n![](image.001.png)  \nJames Coyne  \nDelegate of the Civil Aviation Safety Authority\n\n17 April 2009","sortOrder":0},{"sectionNumber":"AD/CF6/76","sectionType":"part","heading":"AD/CF6/76","content":"## AD/CF6/76","sortOrder":1},{"sectionNumber":"High Pressure Turbine Stage 1 Rotor Disc","sectionType":"part","heading":"High Pressure Turbine Stage 1 Rotor Discs","content":"## High Pressure Turbine Stage 1 Rotor Discs","sortOrder":2},{"sectionNumber":"6/2009","sectionType":"part","heading":"6/2009","content":"## 6/2009","sortOrder":3}],"analysis":{"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"},"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":false,"description":"The directive confines action to the listed HPT stage‑1 rotor disc part numbers and prohibits their installation. It does not expand applicability beyond those listed parts or add obligations beyond removal and installation prohibition; it implements a targeted safety measure tied to the stated crack risk (Applicability; Requirement; Background)."},"complexity_factors":["Specificity of applicability: multiple precise part numbers across several groups require accurate identification of affected engines and parts inventories (Applicability).","Immediate compliance window: mandatory removal within 30 days imposes short notice logistical and maintenance scheduling burdens on operators (Requirement 1; Compliance).","Absolute prohibition: ban on reinstalling the listed discs removes operator discretion to continue using parts pending inspection or repair (Requirement 2).","Technical safety rationale: defect location (aft chamfer of blade dovetail slots) implies inspections or full disc replacement rather than simple fixes, affecting cost and turnaround (Background).","Cross-reference to FAA AD: linkage to FAA AD 2009‑08‑06 may require documentation alignment with foreign regulator actions (Requirement Note 2).","Clear enforcement timing: instrument sets a fixed effective date (4 June 2009), increasing time pressure and reducing phased implementation options (Effective date line).","Low administrative discretion: mandatory removal and prohibition language gives regulators and operators little scope for alternative compliance pathways (Requirement 1 and 2)."],"plain_english_summary":"Requires removal from service of specified General Electric CF6‑80A high‑pressure turbine (HPT) stage‑1 rotor discs and prohibits installing those same discs into any engine. It applies to engines with the listed part numbers (used on aircraft such as Airbus A310 and Boeing 767). The stated purpose is to prevent cracks at the aft chamfer of blade dovetail slots that could cause uncontained engine failure. Operators must comply within 30 days of the effective date and therefore bear the operational and replacement costs."},"kimi_summary":{"content_quality":"ok","complexity_score":2,"scope_assessment":{"changed":false,"description":"This AD maintains its original narrow scope — addressing a specific metallurgical defect in identified HPT rotor disc part numbers. There is no evidence of scope creep; the instrument targets precisely the safety-critical components identified in the FAA's original airworthiness concern."},"complexity_factors":["Single, unambiguous operative requirement (remove and prohibit installation)","Limited conditional logic (only two compliance deadlines: 30 days for removal, immediate for installation ban)","Specific but finite list of affected part numbers (13 distinct P/Ns across 4 groups)","No nested exceptions or complex definitional sections","Clear causal chain in background (crack location → propagation → uncontained failure)","Short document length (approximately 250 words of substantive content)","Single cross-reference to FAA AD for informational purposes only (Note 2)"],"plain_english_summary":"This CASA Airworthiness Directive requires operators and maintenance organisations of GE CF6-80A engines (used on Airbus A310 and Boeing 767) to remove specified high‑pressure turbine rotor discs within 30 days and bans their installation from the effective date. The discs have a design flaw that can crack at the aft chamfer of blade attachment slots, risking catastrophic, uncontained engine failure. The AD became mandatory on 4 June 2009."}},"importantCases":[],"_links":{"self":"/api/acts/ad-cf6-76-high-pressure-turbine-stage-1-rotor-discs","history":"/api/acts/ad-cf6-76-high-pressure-turbine-stage-1-rotor-discs/history","analysis":"/api/acts/ad-cf6-76-high-pressure-turbine-stage-1-rotor-discs/analysis","conflicts":"/api/acts/ad-cf6-76-high-pressure-turbine-stage-1-rotor-discs/conflicts","importantCases":"/api/acts/ad-cf6-76-high-pressure-turbine-stage-1-rotor-discs/important-cases","documents":"/api/acts/ad-cf6-76-high-pressure-turbine-stage-1-rotor-discs/documents"}}