{"id":"F2008L00402","name":"AD/CF6/69 - Fan Disk Coating","slug":"ad-cf6-69-fan-disk-coating","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":119062,"registerId":"commonwealth-F2008L00402-current","compilationNumber":null,"startDate":"2026-04-03","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/CF6/69 | Fan Disk Coating | 3/2008 |\n| --------- | ---------------- | ------ |\n\n| Applicability: | GE CF6-80C2B1 turbofan engine, serial number (S/N) 690203, with fan disk, part number (P/N) 1703M78P11, S/N RPMDA662, installed.Note 1: This engine is installed on, but not limited to, a Boeing 747-300 aeroplane.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |\n| -------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | 1. Strip the Copper-Nickel-Indium (Cu-Ni-In) thermal coating from the pressure faces and slot bottoms of the stage 1 fan disk, and perform a microstructure evaluation. Use 3.A.(2)(a) through 3.A.(2)(b) of GE Service Bulletin (SB) No. CF6-80C2 S/B 72-1121, dated 23 January 2004, to strip the thermal coating and perform the microstructure evaluation.2. Ultrasonic inspect, fluorescent penetrant inspect, and eddy current inspect stage 1 fan disk. Use 3.A.(2)(c) of GE SB No. CF6- 80C2 S/B 72-1121, to inspect the disk.3. Apply Cu-Ni-In thermal coating to the pressure faces and slot bottoms of the stage 1 fan disks, using 3.A.(2)(d) of GE SB No. CF6-80C2 S/B 72-1121.Later revisions of the above SB(s), approved by the United States Federal Aviation Administration (FAA) as an Alternate Method of Compliance (AMOC) to FAA AD 2007-24-07, are considered acceptable for compliance with the equivalent Requirements of this AD.Note 2: FAA AD 2007-24-07 Amdt 39-15273 dated 15 November 2007 refers. |\n| Compliance:    | Within 3,500 cycles-since-last Cu-Ni-In thermal spray coating of the dovetail slots, but no later than 30 June 2008, unless previously accomplished.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              |\n|                | This Airworthiness Directive becomes effective on 13 March 2008.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |\n\n| Background: | This AD results from a report that a repair shop did not meet the process requirements when applying Cu-Ni-In thermal coating to certain stage 1 fan disks. The actions detailed in this AD are to prevent possible uncontained release of multiple fan blades, resulting in damage to the aeroplane. |\n| ----------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n\n![](image.001.png)  \nCharles Lenarcic  \nDelegate of the Civil Aviation Safety Authority\n\n21 January 2008","sortOrder":0},{"sectionNumber":"AD/CF6/69","sectionType":"part","heading":"AD/CF6/69","content":"## AD/CF6/69","sortOrder":1},{"sectionNumber":"Fan Disk Coating","sectionType":"part","heading":"Fan Disk Coating","content":"## Fan Disk Coating","sortOrder":2},{"sectionNumber":"3/2008","sectionType":"part","heading":"3/2008","content":"## 3/2008","sortOrder":3}],"analysis":{"flash_summary":{"complexity_score":4,"scope_assessment":{"changed":false,"description":"The AD does not expand the population beyond the specific engine/part identified; it prescribes remedial stripping, inspection and re‑coating for disks where the Cu‑Ni‑In application process may have been deficient. The directive remains corrective and narrowly targeted to the reported repair‑shop issue (Applicability; Requirement; Background)."},"complexity_factors":["Very narrow applicability to a single engine model, serial number and part number, increasing case‑specific administrative tracking (Applicability).","Technical steps require controlled stripping, microstructure evaluation and three distinct NDT methods (ultrasonic, fluorescent penetrant, eddy current), requiring specialist skills and equipment (Requirement: 1–3).","Work must follow multiple specific GE SB subsections, so compliance depends on precise procedural conformity to the SB text (Requirement: references to GE SB No. CF6‑80C2 S/B 72‑1121, 3.A.(2)(a)–(d)).","Compliance timing combines a cycles‑since‑last‑coating metric and a firm calendar cutoff (3,500 cycles or 30 June 2008), requiring maintenance records validation and schedule coordination (Compliance).","Acceptance of later SB revisions only if approved as FAA AMOC introduces regulatory dependence on FAA approvals and potential administrative delay (Requirement: Note 2).","Root cause is an identified repair‑shop process failure, so the AD is corrective and may necessitate investigation/documentation by operators and repair organisations (Background)."],"plain_english_summary":"This Airworthiness Directive requires removal of a copper‑nickel‑indium (Cu‑Ni‑In) thermal spray from the pressure faces and dovetail slot bottoms of a specific stage‑1 fan disk on a GE CF6‑80C2B1 engine, followed by a microstructure check, ultrasonic/penetrant/eddy‑current inspections, and reapplication of the coating using the GE Service Bulletin procedures. It applies to the named engine/part and must be done within 3,500 cycles‑since‑last coating or by 30 June 2008.\n\nThe AD responds to an identified improper repair process and aims to reduce the risk of uncontained fan‑blade release; operators and maintenance providers bear the work, inspection and downtime costs and must follow the cited SB and FAA AMOC references (Requirements; Compliance; Note 2)."},"flash_summary_failed":{"failed":true,"reason":"A positive credit balance is required for all requests, including BYOK, so fallback providers remain available. Add credits at https://vercel.com/d?to=%2F%5Bteam%5D%2F%7E%2Fai%3Fmodal%3Dtop-up to continue.","source":"analysis-cron"},"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This is a targeted, one-off safety directive addressing a specific manufacturing defect in a single identified component. The scope remains precisely limited to the original safety concern — a repair shop's process deviation on one specific fan disk. There is no evidence of scope creep; the AD does not expand to cover other engines, other part numbers, or broader fleet-wide concerns."},"complexity_factors":["Highly specific applicability — applies to exactly one engine with one specific part (S/N 690203, P/N 1703M78P11, S/N RPMDA662)","Technical terminology requiring aviation engineering knowledge (dovetail slots, eddy current inspection, fluorescent penetrant inspection, microstructure evaluation)","Reference to external technical documents (GE Service Bulletin CF6-80C2 S/B 72-1121) for detailed procedures rather than spelling them out","Cross-reference to US FAA AD 2007-24-07 and AMOC (Alternate Method of Compliance) provisions","Dual compliance threshold (3,500 cycles OR 30 June 2008, whichever is earlier)","Short document (approximately 300 words) with minimal conditional logic"],"plain_english_summary":"This CASA Airworthiness Directive requires urgent corrective work on one General Electric CF6-80C2B1 engine (S/N 690203) because an improperly applied Copper‑Nickel‑Indium coating on a fan disk may lead to fan blade release and an uncontained engine failure. The owner/operator and maintenance organisations must strip the faulty coating, perform ultrasonic, fluorescent‑penetrant and eddy‑current inspections, and correctly reapply the coating per GE Service Bulletin — within 3,500 flight cycles or by 30 June 2008, whichever is earlier."}},"importantCases":[],"_links":{"self":"/api/acts/ad-cf6-69-fan-disk-coating","history":"/api/acts/ad-cf6-69-fan-disk-coating/history","analysis":"/api/acts/ad-cf6-69-fan-disk-coating/analysis","conflicts":"/api/acts/ad-cf6-69-fan-disk-coating/conflicts","importantCases":"/api/acts/ad-cf6-69-fan-disk-coating/important-cases","documents":"/api/acts/ad-cf6-69-fan-disk-coating/documents"}}