Airworthiness Directive · Amendment 39-13402 · General Electric Company CF34-8C1 Series and CF34-8C5 Series Turbofan Engines
General Electric Company CF34-8C1 Series and CF34-8C5 Series Turbofan Engines
Superseded. A later AD replaced this one: AD 2005-07-06. Comply with the one in force.
This AD applies to General Electric Company (GE) CF34-8C1 series and CF34-8C5 series turbofan engines, with master variable geometry (VG) actuators, part number 4120T02P02, serial number (SN) APM238AE, and SNs APM242AE and up, installed. These engines are installed on, but not limited to, Bombardier Inc. Model CL-600-2C10 (CRJ-700 & 701) and CL-600-2D24 (CRJ-900) airplanes.
The FAA is adopting a new airworthiness directive (AD) for General Electric Company (GE) CF34-8C1 series and CF34-8C5 series turbofan engines, with certain serial number (SN) master variable geometry (VG) actuators installed. This AD requires initial and repetitive reviews of the airplane Maintenance Data Computer (MDC) for master VG actuator fault messages, and if the MDC is inoperative, reviews of the Engine Indication and Crew Alerting System (EICAS) for fault messages. This AD also requires replacement of actuators reported faulty by the Full Authority Digital Engine Control (FADEC). This AD results from nine reports of master VG actuator electrical signal faults, one report of which was a dual-channel fault, resulting in the FADEC commanding the engine power to idle. We are issuing this AD to prevent VG master actuator dual-channel electrical signal faults: [sbull] Which will cause an uncommanded reduction of thrust to idle with a subsequent loss of the ability to advance thrust above idle; and [sbull] Could result in a multi-engine loss of thrust if dual- channel faults occur on more than one engine simultaneously.
