Incident Overview
While west of the airport, the flight crew received clearance for the Bay Visual Approach to Runway 16 Right. The First Officer, who was flying, executed a right turn over Elliott Bay and aligned the aircraft with what he believed to be Runway 16 Right. In reality, the surface was Taxiway Tango. At approximately one mile from the end of the taxiway, the First Officer observed a yellow X marker located just off the northern end of the intended landing surface. Recognizing the error, he initiated a sidestep maneuver toward Runway 16 Right. The approach and landing on Runway 16 Right were completed without further incident, and the aircraft taxied to the gate for normal passenger deplanement.
Details from Investigation
According to recorded radar tracking data, at the time the First Officer began the sidestep turn, the aircraft was approximately 600 feet above ground level. The investigation noted that the size and shape of Taxiway Tango closely resembled a runway, contributing to the First Officer's misidentification. Glare on the wet surfaces prevented him from clearly seeing any markings identifying the surface as a taxiway, although he was eventually able to discern the Runway 16 Right identification markings. The Captain had correctly identified the runway when the aircraft first rolled out on final approach; however, flight deck distractions kept him from recognizing that the First Officer was lined up on the taxiway until the sidestep was initiated.