Officials release E-4 engine accident report Published June 7, 2004 LANGLEY AIR FORCE BASE, Va. (AFPN) -- Two separate mechanical failures led to $3.8 million in engine damage to an E-4B National Airborne Operations Center aircraft here Feb. 3, according to a report Air Force officials released June 7.During the mission, the crew saw indications of extremely high gas temperature, excessive fuel flow and vibration in the No. 4 engine. The crew shut down the engine, declared an in-flight emergency and landed the aircraft safely.The aircraft is assigned to the 1st Airborne Command Control Squadron at Offutt AFB, Neb.According to the Air Combat Command Accident Investigation Board report, a turbine blade fractured and moved through subsequent sections of the turbine, damaging the No. 4 engine. Additionally, a shroud, the casing that surrounds the turbine blades to increase air flow, dropped into the turbine air path causing extreme wear to several turbine blades. The investigation showed the mechanical failures were unrelated and could not determine which failure happened first.There were no injuries or other damage to government or private property. (Courtesy of ACC News Service)