The FAA has ordered General Electric to repair 300 CF34-8C and CF34-8E turbofan engines because of bad valves which have caused two engine fires. The engines power Bombardier CRJ700s and 900s as well as Embraer 170/175 aircraft. This will effect 15 percent of the fleet, encompassing engines built between 2001 and 2006.
The issue to be repaired is caused by a fault in the operability bleed valve, which takes air out of the engine’s compressor during start-up. As the valve fittings age they occasionally leak, and twice have caused an engine fire. One incident occurred on takeoff, but the engine was shut down and the fire-extinguishing system activated before the aircraft landed safely. The other fire occurred after landing when a fire alert sounded, the engine was shut down, and the aircraft taxied to the gate.
