{"id":"F2010L02678","name":"AD/CF34/18 - Master Variable Geometry (VG) Actuators","slug":"ad-cf34-18-master-variable-geometry-vg-actuators","collection":"legislative_instrument","jurisdiction":"commonwealth","status":"in_force","isInForce":true,"actNumber":null,"makingDate":null,"administeringDepartment":null,"currentVersion":{"id":84635,"registerId":"commonwealth-F2010L02678-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/CF34/18 | Master Variable Geometry (VG) Actuators | 20/2010 |\n| ---------- | --------------------------------------- | ------- |\n\n| Applicability: | General Electric Company CF34 engines as specified in FAA AD 2005-07-09.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |\n| -------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |\n| Requirement:   | Unless already accomplished, perform the initial review and action in accordance with the requirements of FAA AD 2005-07-09.Repeat the review and action in accordance with the requirements of FAA AD2005-07-09.Later revisions to GE Alert Service Bulletin No CF34-8E-AL S/B 75-A0001, 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 2005-07-09, 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/CF34/18","sectionType":"part","heading":"AD/CF34/18","content":"## AD/CF34/18","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":{"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 AD maintains its original narrow scope: addressing a specific electrical fault in VG master actuators on CF34 engines. It does not expand beyond this safety-critical hardware issue."},"complexity_factors":["Short, single-purpose directive (approximately 250 words of substantive content)","Only 2 defined technical terms (VG Actuators, AMOC — Alternate Method of Compliance)","Heavy reliance on external documents: delegates all technical requirements to FAA AD 2005-07-09 and GE Alert Service Bulletin CF34-8E-AL S/B 75-A0001","Simple conditional structure: one main requirement with a single exception/alternative compliance pathway","No nested exceptions or multi-layered logic","Clear, linear compliance timeline (effective date of 31 October 2010)"],"plain_english_summary":"This CASA Airworthiness Directive mandates owners/operators of certain General Electric CF34 engines to inspect and repair the Variable Geometry (VG) master actuators because a dual‑channel electrical fault can force engines to an uncommanded idle and prevent power increase.  \n\nCompliance requires initial and repeating inspections and corrective actions per the referenced FAA AD or later approved GE service bulletin revisions. It's legally required to prevent multi‑engine thrust loss and in‑flight emergencies."},"flash_summary":{"complexity_score":3,"scope_assessment":{"changed":false,"description":"No. The AD adopts the corrective scope of FAA AD 2005-07-09: perform initial and repeat reviews/actions to address dual-channel electrical faults in the VG master actuator and permits later GE Alert Service Bulletin revisions as an alternate method of compliance. It does not broaden applicability or add new corrective measures beyond the referenced FAA requirements (Applicability; Requirement)."},"complexity_factors":["Cross-reference to an external FAA AD (FAA AD 2005-07-09) requiring readers to consult another instrument","Technical subject matter (VG master actuator electrical faults) requiring engineering or maintenance expertise","Recurring inspection/action obligations increase ongoing compliance burden","Acceptance of later GE Alert Service Bulletin revisions as AMOC introduces variable compliance paths","Safety-critical operational consequence (loss of thrust) raises enforcement and documentation requirements","Specified effective date for mandatory compliance (31 October 2010)"],"plain_english_summary":"This Airworthiness Directive requires operators of General Electric CF34 engines identified in FAA AD 2005-07-09 to perform an initial and recurring inspection and any corrective actions on the master Variable Geometry (VG) actuator to prevent dual-channel electrical faults that can cause an uncommanded thrust reduction (Applicability; Requirement; Background). Operators must follow the FAA AD procedures; CASA accepts later revisions of GE Alert Service Bulletin CF34-8E-AL S/B 75-A0001 as an alternate method of compliance. The AD takes effect 31 October 2010 (Requirement; Compliance)."}},"importantCases":[],"_links":{"self":"/api/acts/ad-cf34-18-master-variable-geometry-vg-actuators","history":"/api/acts/ad-cf34-18-master-variable-geometry-vg-actuators/history","analysis":"/api/acts/ad-cf34-18-master-variable-geometry-vg-actuators/analysis","conflicts":"/api/acts/ad-cf34-18-master-variable-geometry-vg-actuators/conflicts","importantCases":"/api/acts/ad-cf34-18-master-variable-geometry-vg-actuators/important-cases","documents":"/api/acts/ad-cf34-18-master-variable-geometry-vg-actuators/documents"}}