Control was lost during a 3-engine missed ILS approach procedure and the aircraft crashed. Failure of the aircraft rudder hydraulic actuator support fitting led to the loss of left rudder control. The loss of control situation was worsened by the degraded external visual clues (600 feet overcast; 1200 m visibility in fog haze and smoke). PROBABLE CAUSE: “The failure of the aircraft rudder hydraulic actuator support fitting. The failure of the fitting resulted in the inapparent loss of left rudder control which, under the conditions of the flight, precluded the pilots’ ability to maintain directional control during a simulated engine-out missed-approach. The existing weather conditions degraded external visual cues, thereby hampering rapid assessment of aircraft performance by the flight check captain.”