Seattle-Tacoma Inyternational Airport
Aircraft Accident/Incident Report

Seattle, Washington 98188
Tuesady, February 24, 2004 9:30 PST

While west of the airport, the flight crew was cleared for the Bay Visual Approach to Runway 16 Right. The First Officer, who was flying at the time, made a right turn over Elliott Bay and lined up on what he believed to be Runway 16 Right, but was in fact Taxiway Tango. When the aircraft was about one mile from the end of the taxiway, the first officer noticed a yellow X located just off the northern end of the surface he intended to land on. Upon realizing he was lined up on the wrong surface, he initiated a sidestep to Runway 16 Right. He subsequently completed an uneventful landing on Runway 16 Right, and taxied to the gate for a normal deplanement of the passengers. According to recorded radar tracking data, at the time of the turn to initiate the sidestep, the aircraft was approximately 600 feet above the ground (AGL). The size and shape of the taxiway made it look very much like a runway to the First Officer, and although he was eventually able to see the Runway 16 Right identification markings, because of the glare on the wet surfaces, he never did clearly see any markings that indicated Taxiway Tango was a taxiway. Although the Captain had correctly identified the runway surface when the aircraft first rolled out on final, flight deck distractions kept him from realizing that the first Officer was lined up on the taxiway until the sidestep maneuver was initiated.

The First Officer's misidentification of the parallel taxiway as the active runway, resulting in the need for a sidestep maneuver while on short final for a full-stop landing. Factors include sun-glare from wet paved surfaces, a visual illusion created by the size and shape of the taxiway, and the Captain's failure to adequately monitor the First Officer’s approach.