{"id":"F2007L04270","name":"AD/CF6/67 - Compressor Rear Frame Cracks","slug":"ad-cf6-67-compressor-rear-frame-cracks","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":70499,"registerId":"commonwealth-F2007L04270-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/CF6/67 | Compressor Rear Frame Cracks | 12/2007 |\n| --------- | ---------------------------- | ------- |\n\n```html\n

Applicability:

General Electric Company (GE) CF6-80E1A1, CF6-80E1A2, CF6-80E1A3,
CF6-80E1A4, and CF6-80E1A4/B model turbofan engines with compressor rear frame (CRF) part numbers (P/Ns) 1520M26G03/G06/G08/G11/G12 installed.

Note 1: These engines are installed on, but not limited to, Airbus Industrie A330 series aeroplanes.

Requirement:

Revise GE's Instructions for Continued Airworthiness ALS, and for air carrier operations, revise the approved continuous airworthiness maintenance program, by adding the information detailed below under the headings detailed below of this AD:

- Table 1. - Inspection Compliance Schedule

- Module - Level Inspection of CRFs

- Piece - Part Level Inspection of CRFs

- Determining CSN of the Compressor Rear Frame

Table 1.--Inspection Compliance Schedule

If CRF P/Ns 1520M26G03 / G06 / G08 / G11 / G12 are:

Then Initially Inspect:

And Repetitively Inspect:

(1) Operated at a
CF6-80E1A3 or
CF6-80E1A4/B engine rating.

Before 12,200 cycles-since-new (CSN).

Within every 6,300 cycles-since-last-inspection (CSLI), except that igniter pad holes on CRFs with P/Ns 1520M26G03 / G06 / G08, must be inspected within every 4,800 CSLI.

(2) Operated at a
CF6-80E1A4 engine rating.

Before 13,700 CSN.

Within every 6,300 CSLI, except that igniter pad holes on CRFs with P/Ns 1520M26G03 / G06 / G08, must be inspected within every 6,100 CSLI.

(3) Operated at a
CF6-80E1A1 or
CF6-80E1A2 engine rating.

Before 14,200 CSN.

Within every 6,300 CSLI.

\n```\n\n| | Module - Level Inspection of CRFs1. For CRF P/Ns 1520M26G03/G06/G08/G11/G12, at module level:a. Clean and eddy current inspect (ECI) the locations numbered 3 through 8.b. Information on these locations can be found in figure 801, sheets 2, 3, and 4, of CF6-80E1 Engine Manual No. GEK 99376, Section 05-21-01. The remaining engine manual references in this AD are to No. GEK 99376.c. Information on cleaning and ECI can be found in CF6-80E1 Engine Manual, Section 72-00-34, COMPRESSOR REAR FRAME ASSEMBLY - INSPECTION 001, Subtask 72-00-34-250-001.d. For CRF P/Ns 1520M26G03/G06/G08, clean and fluorescent penetrant inspect (FPI) the locations numbered 1 and 2.e. Information on these locations can be found in figure 801, sheet 1, ofCF6-80E1 Engine Manual, Section 05-21-01.f. Information on cleaning and FPI can be found in CF6-80E1 Engine Manual, Section 72-00-34, COMPRESSOR REAR FRAME ASSEMBLY - INSPECTION 001, Subtask 72-00-34-230-051.Piece - Part Level Inspection of CRFs1. For CRF P/Ns 1520M26G03/G06/G08/G11/G12, at piece-part level:a. Clean and FPI the locations numbered 3 through 8.b. Information on these locations can be found in figure 801, sheets 2, 3, and 4, of CF6-80E1 Engine Manual, Section 05-21-01.c. Information on cleaning and FPI can be found in CF6-80E1 Engine Manual, Section 72-34-01, COMPRESSOR REAR FRAME - INSPECTION 001, Subtask 72-34-01-200-003.d. For CRF P/Ns 1520M26G03/G06/G08, clean and FPI the locations numbered 1 and 2.e. Information on these locations can be found in figure 801, sheet 1, ofCF6-0E1 Engine Manual, Section 05-21-01.f. Information on cleaning and FPI can be found in CF6-80E1 Engine Manual, Section 72-34-01, COMPRESSOR REAR FRAME - INSPECTION 001, Subtask 72-34-01-200-003. |\n| --- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n\n| | Determining CSN of the Compressor Rear Framea. Air carriers and operators must use engine operating records to determine the CSN of the compressor rear frame. If the number of cycles accumulated since new cannot be established, inspect the CRF within 300 cycles-in-service after the effective date of this AD.b. For compressor rear frames that have operated in multiple engine models or thrust ratings, information on correct cycle counting can be found in Method 1 or Method 2 of CF6-80E1 Engine Manual No. GEK 99376, Section05-11-00, LIFE LIMITS OF ENGINE ROTATING PARTS.DefinitionFor the purposes of this AD, piece-part level means that the CRF is removed and disassembled using the disassembly instructions in GE's engine manual.Note 2: FAA AD 2007-18-10 Amdt 39- 15190 dated 29 August 2007 refers. |\n| ----------- | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Compliance: | Within the next 30 days after the effective date of this AD, unless previously accomplished. |\n| | This Airworthiness Directive becomes effective on 22 November 2007. |\n| Background: | This AD requires enhanced inspections of the CF6-80E1 series turbofan engine CRFs, for cracks to prevent rupture of the CRF, which could result in an under-cowl engine fire. |\n\n![](image.001.png) \nCharles Lenarcic \nDelegate of the Civil Aviation Safety Authority\n\n24 September 2007","sortOrder":0},{"sectionNumber":"AD/CF6/67","sectionType":"part","heading":"AD/CF6/67","content":"## AD/CF6/67","sortOrder":1},{"sectionNumber":"Compressor Rear Frame Cracks","sectionType":"part","heading":"Compressor Rear Frame Cracks","content":"## Compressor Rear Frame Cracks","sortOrder":2},{"sectionNumber":"12/2007","sectionType":"part","heading":"12/2007","content":"## 12/2007","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":6,"scope_assessment":{"changed":false,"description":"This AD stays within the original safety purpose: to detect and address cracks in the compressor rear frame to prevent rupture and possible under‑cowl fire. The instrument prescribes inspection schedules, methods and recordkeeping changes; it does not introduce additional unrelated regulatory obligations or expand into new regulatory domains. It tightens and specifies inspection requirements for the targeted CRF part numbers and engine ratings but does not materially change the scope beyond addressing that safety risk."},"complexity_factors":["Multiple affected CRF part numbers (5 P/Ns listed: 1520M26G03, G06, G08, G11, G12)","Three different engine‑rating cases with different initial CSN thresholds and repeat intervals (Table 1)","Different repeat inspection intervals for general locations and for igniter pad holes (special shorter intervals for certain P/Ns)","Two inspection levels with different techniques and scope (module‑level: ECI and sometimes FPI; piece‑part level: FPI after removal and disassembly)","Numerous cross‑references to GE CF6‑80E1 engine manual sections and specific figure/sheet numbers for locations and procedures","Definition and procedural requirement to determine cycles‑since‑new (CSN) from operating records, plus fallback rule (inspect within 300 cycles if CSN unknown)","Operational compliance deadline (update maintenance program within 30 days of effective date) and an effective date (creates short implementation window)","Conditional logic for engines that have operated in multiple models/thrust ratings requiring specified cycle‑counting Method 1 or 2","Terminology distinctions (module‑level vs piece‑part level) that change who can perform the work and what scope is required","Reference to an associated FAA AD (cross‑jurisdictional regulatory linkage)"],"plain_english_summary":"**What this instrument does (mechanically)\n\n- Requires operators of certain General Electric CF6-80E1 turbofan engines fitted with compressor rear frames (CRFs) part numbers 1520M26G03, G06, G08, G11 or G12 to add and follow new inspection rules. (Applicability table.)\n- Requires revision of GE's Instructions for Continued Airworthiness and the operators' approved continuous airworthiness maintenance programs to include the inspections, schedules and procedures set out in the directive. (Requirement section; Table 1.)\n- Sets different initial inspection deadlines depending on the engine model/rating and the CRF cycles-since-new (CSN), and sets repeated inspection intervals expressed in cycles-since-last-inspection (CSLI). There are three engine-rating cases with different initial CSN thresholds and repeat intervals (see Table 1).\n- Requires two inspection levels:\n - Module-level inspections (done with the CRF in the engine/module): cleaning and eddy‑current inspection (ECI) for locations 3–8; for P/Ns G03/G06/G08 also fluorescent penetrant inspection (FPI) of igniter pad holes (locations 1–2). (Module‑level inspection text.)\n - Piece‑part level inspections (CRF removed and disassembled): clean and FPI locations 3–8; and for P/Ns G03/G06/G08 also FPI of locations 1–2. (Piece‑part inspection text; definition of piece‑part level.)\n- Provides where to find the exact inspection locations and detailed cleaning/inspection procedures in GE CF6‑80E1 engine manual No. GEK 99376 (specific section and figure references are quoted). (Multiple cross‑references in the body.)\n- Requires operators to determine the CRF cycles‑since‑new from engine operating records. If CSN cannot be determined, the CRF must be inspected within 300 cycles-in-service after the effective date. Guidance is given for cycle counting when CRFs have operated in multiple engine models or thrust ratings. (Determining CSN section.)\n- Sets a short compliance window for adopting the change: the AD must be incorporated into the maintenance program within 30 days of the effective date. (Compliance.)\n\nWho is affected\n\n- Airlines, air carriers, and other operators that use GE CF6‑80E1 engines fitted with the listed CRF part numbers. This includes, but is not limited to, some Airbus A330 operators (Note in applicability).\n- Maintenance organisations and MROs that perform module‑level and piece‑part work on those CRFs, because they must perform and record ECI and FPI inspections and follow the specific GE manual procedures referenced.\n\nWhy it matters (stated purpose and practical consequences)\n\n- The stated purpose is to detect cracks in the compressor rear frame early enough to prevent CRF rupture, which the AD says could lead to an under‑cowl engine fire. (Background.)\n\nPractical effects, costs and incentives\n\n- Who pays: the operator/airline bears the direct cost of additional inspections, any piece‑part removals, non‑routine labour and possible part replacement or early removal from service.\n- Operational impact: some inspections require module removal or piece‑part disassembly, which creates aircraft/engine downtime and may affect aircraft utilisation and scheduling.\n- Compliance and administrative burden: operators must update approved maintenance programs and keep accurate cycle counts for CRFs; inability to prove CSN triggers a mandatory inspection within 300 cycles. That raises record‑keeping importance and may increase demand for historical record reconciliation.\n- Technical dependency and discretion: the AD references GE's engine manual for the inspection locations and techniques, so operators must follow GE's published procedures; inspections rely on ECI and FPI techniques and the availability of suitably qualified technicians and equipment.\n- Concentrated benefit / diffuse cost: the safety benefit (reduced risk of CRF rupture) accrues broadly to airworthiness and passengers, while the immediate costs (inspection time, labour, parts) are concentrated on operators and MRO providers.\n\nTrade‑offs and implementation risks\n\n- Opportunity cost: resources devoted to these inspections (shop time, skilled personnel) cannot be used elsewhere; smaller operators may face proportionally higher per‑engine costs.\n- Substitution effects: operators might choose more frequent module‑level inspections instead of piece‑part removals where allowed, or elect earlier part replacement to avoid repetitive inspection costs; either choice affects maintenance spending and spare‑parts demand.\n- Capture and rent‑seeking risk: the AD directs operators to GE manual procedures for methods and locations; that creates dependency on the OEM documentation for compliance but the AD itself establishes the inspection obligation (the AD is the regulatory requirement). The AD does not create new certification discretion beyond requiring adherence to specified procedures.\n\nSummary statement\n\n- Mechanically, this instrument imposes mandated initial and repetitive inspection schedules (with different timelines by engine rating), prescribes specific inspection techniques and locations (via referenced GE manual figures), and requires operators to update maintenance programs and maintain cycle records for the specified CF6‑80E1 CRFs. The stated regulatory objective is to find and fix CRF cracks to prevent structural failure and possible under‑cowl fire. The concrete costs fall on operators and maintenance providers (inspection labour, downtime, possible part removal/replacement), while the procedural dependency on GE manuals shapes how inspections are performed. (Requirement and Background sections.)"},"kimi_summary":{"content_quality":"ok","complexity_score":6,"scope_assessment":{"changed":false,"description":"This AD maintains focused scope on its original safety purpose — preventing compressor rear frame cracks in specific GE CF6-80E1 engine variants. The document implements a targeted inspection regime without expanding beyond the identified safety risk."},"complexity_factors":["Multiple engine sub-models with different compliance thresholds (CF6-80E1A1/A2/A3/A4/A4/B) requiring distinct inspection intervals","Nested conditional logic: inspection frequency varies by both engine rating AND specific part number (P/N 1520M26G03/G06/G08 vs G11/G12)","Technical cross-references to external GE engine manual (GEK 99376) with specific section, figure, and subtask numbers","Dual inspection pathways: 'module-level' (engine partially assembled) vs 'piece-part level' (component removed and disassembled)","Specialised aviation terminology requiring domain knowledge: CSN (cycles-since-new), CSLI (cycles-since-last-inspection), ECI (eddy current inspection), FPI (fluorescent penetrant inspection)","Cycle-counting complexity for parts that have operated across multiple engine models or thrust ratings, requiring Method 1 or Method 2 calculations","Fallback provision for unknown cycle history requiring alternative compliance timeline"],"plain_english_summary":"This CASA Airworthiness Directive requires operators of CF6-80E1 engines (e.g., A330) to add mandatory inspections of the compressor rear frame for cracks, using eddy‑current and fluorescent‑penetrant techniques. Initial and recurring checks at specified flight‑cycle intervals are required to prevent CRF rupture and possible engine fire.\n\nAffected airlines and maintenance organisations must amend maintenance programs within 30 days of the AD."}},"importantCases":[],"_links":{"self":"/api/acts/ad-cf6-67-compressor-rear-frame-cracks","history":"/api/acts/ad-cf6-67-compressor-rear-frame-cracks/history","analysis":"/api/acts/ad-cf6-67-compressor-rear-frame-cracks/analysis","conflicts":"/api/acts/ad-cf6-67-compressor-rear-frame-cracks/conflicts","importantCases":"/api/acts/ad-cf6-67-compressor-rear-frame-cracks/important-cases","documents":"/api/acts/ad-cf6-67-compressor-rear-frame-cracks/documents"}}