{"id":"F2010L02679","name":"AD/CF34/19 - Master Variable Geometry (VG) Actuators","slug":"ad-cf34-19-master-variable-geometry-vg-actuators","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":84636,"registerId":"commonwealth-F2010L02679-current","compilationNumber":null,"startDate":"2026-04-02","status":"InForce","reasons":null,"registeredAt":null},"sections":[{"sectionNumber":"General Electric Turbine Engines - CF34 ","sectionType":"division","heading":"General Electric Turbine Engines - CF34 Series","content":"### General Electric Turbine Engines - CF34 Series\n\n| AD/CF34/19 | Master Variable Geometry (VG) Actuators | 20/2010 |\n| ---------- | --------------------------------------- | ------- |\n\n| Applicability: | General Electric Company CF34 engines as specified in FAA AD 2005-07-06.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                    |\n| -------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | Unless already accomplished, perform the initial review and action in accordance with the requirements of FAA AD 2005-07-06.Repeat the review and action in accordance with the requirements of FAA AD 2005-07-06.Later revisions to GE Alert Service Bulletin No CF34-8C-AL S/B 75-A0007, Revision 3, dated February 14, 2005, approved by the United States Federal Aviation Administration (FAA) as an Alternate Method of Compliance (AMOC) to FAA AD 2005-07-06, are considered acceptable for compliance with the equivalent Requirements of this AD. |\n| Compliance:    | As specified in the Requirement Document with a revised effective date of31 October 2010.                                                                                                                                                                                                                                                                                                                                                                                                                                                                   |\n|                | This Airworthiness Directive becomes effective on 31 October 2010.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |\n| Background:    | This AD is issued to prevent dual-channel electrical signal faults in the VG master actuator, which will cause an un-commanded reduction of thrust to idle with a subsequent loss of the ability to advance thrust above idle. This could result in a multi-engine loss of thrust if dual-channel faults occur on more than one engine simultaneously.                                                                                                                                                                                                      |\n\n![](image.001.png)  \n  \nMike Higgins  \nDelegate of the Civil Aviation Safety Authority\n\n5 October 2010","sortOrder":0},{"sectionNumber":"AD/CF34/19","sectionType":"part","heading":"AD/CF34/19","content":"## AD/CF34/19","sortOrder":1},{"sectionNumber":"Master Variable Geometry (VG) Actuators","sectionType":"part","heading":"Master Variable Geometry (VG) Actuators","content":"## Master Variable Geometry (VG) Actuators","sortOrder":2},{"sectionNumber":"20/2010","sectionType":"part","heading":"20/2010","content":"## 20/2010","sortOrder":3}],"analysis":{"kimi_summary":{"content_quality":"ok","complexity_score":3,"scope_assessment":{"changed":false,"description":"This is a standard Airworthiness Directive with a narrow, specific safety purpose — addressing a known electrical fault in a particular engine component. It has not expanded beyond its original intent of preventing uncommanded thrust reduction."},"complexity_factors":["Short, single-purpose safety directive with only one technical requirement","No defined terms section — relies entirely on external FAA document for technical specifications","Single cross-reference to FAA AD 2005-07-06 and GE service bulletin CF34-8C-AL S/B 75-A0007","Simple conditional structure: 'Unless already accomplished' is the only exception","No nested exceptions or complex logical operators","Total length is approximately 200 words of substantive content"],"plain_english_summary":"This CASA Airworthiness Directive mandates inspections and repairs to fix a dual‑channel electrical fault in the Variable Geometry master actuators of certain General Electric CF34 engines. It targets airlines and maintenance organisations operating CF34‑powered regional jets, requiring follow‑up of the FAA’s inspection/repair instructions to prevent possible sudden loss of thrust and multi‑engine power failures."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"The AD incorporates and enforces the requirements of FAA AD 2005‑07‑06 for the CF34 engines and accepts a specific GE Alert Service Bulletin revision as an alternate method of compliance. This aligns with the stated safety purpose (preventing dual‑channel VG master actuator faults) and does not broaden or narrow the population of engines affected beyond the FAA AD; it modifies acceptable compliance methods rather than the substantive scope."},"complexity_factors":["Cross-reference dependency: compliance is achieved by following FAA AD 2005‑07‑06 rather than self-contained requirements (Requirement / Applicability).","Recurring obligation: initial review/action plus mandatory repeat reviews in line with the FAA AD (Requirement).","Alternative compliance mechanism: later revisions of GE Alert Service Bulletin No CF34‑8C‑AL S/B 75‑A0007 Rev 3 are explicitly accepted as an AMOC, creating regulatory choice for operators (Requirement).","Safety‑critical technical focus: addresses electrical dual‑channel faults in the VG master actuator with high operational risk (Background).","Limited scope of affected equipment: applies only to CF34 engines specified in the referenced FAA AD, limiting regulatory footprint but requiring operators to check applicability (Applicability).","Compliance timing: an explicit effective/compliance date is set (31 October 2010), creating a clear deadline for actions (Compliance)."],"plain_english_summary":"This Airworthiness Directive requires operators of specified General Electric CF34 engines to carry out the initial and recurring inspections and corrective actions set out in FAA AD 2005‑07‑06, with GE Alert Service Bulletin No CF34‑8C‑AL S/B 75‑A0007 Rev 3 accepted as an alternate method of compliance. It targets a dual‑channel electrical fault in the variable‑geometry (VG) master actuator that can command thrust to idle and stop thrust advance; operators must comply by 31 October 2010."},"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"}},"importantCases":[],"_links":{"self":"/api/acts/ad-cf34-19-master-variable-geometry-vg-actuators","history":"/api/acts/ad-cf34-19-master-variable-geometry-vg-actuators/history","analysis":"/api/acts/ad-cf34-19-master-variable-geometry-vg-actuators/analysis","conflicts":"/api/acts/ad-cf34-19-master-variable-geometry-vg-actuators/conflicts","importantCases":"/api/acts/ad-cf34-19-master-variable-geometry-vg-actuators/important-cases","documents":"/api/acts/ad-cf34-19-master-variable-geometry-vg-actuators/documents"}}