Incident Summary
Shortly after touching down, the aircraft began veering slightly to the left. The first officer, who was flying, applied rudder to maintain control. The captain then took control of the aircraft at a speed above 60 knots. The captain realigned the aircraft to the runway centerline and called for the condition levers (CL) to be set to the minimum position at approximately 60 to 70 knots. At that point, the aircraft again veered left. The captain was unable to maintain directional control as the aircraft turned sharply left. The right wing tip and right propeller contacted the runway surface. The aircraft then collided with a runway sign before stopping partially off the runway.
Aircraft Procedures
Horizon Air's standard operating procedures specified that the condition levers should be placed in the maximum position when the main landing gear touched down. After landing, the captain had discretion to move the levers to the minimum position. With the CL in the maximum position, the flight crew had up to 10 degrees of nose-wheel steering authority through the rudder pedals. With the CL in the minimum range, 60 degrees of nose-wheel steering was available through the tiller. The Dornier 328-100 Airplane Operating Manual stated under Standard Landing Procedures that the condition levers should be retarded to the minimum position at a 'safe speed.'
Aftermath
Shortly after the accident, Horizon Air revised its landing procedures. The new procedure required that the aircraft be at taxi speed (below 30 knots) before the captain commands the condition levers to the minimum position. Investigators found no mechanical failure or malfunction with the aircraft.