Light Transport; Low Wing; 2 Turbojet Eng
Air Traffic Control Fully Certified
Air Traffic Control Time Certified In Pos 1 (yrs) 1
Situational Awareness
ATC Issue All Types; Conflict NMAC; Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Clearance
Air Traffic Control Issued New Clearance; Flight Crew Requested ATC Assistance / Clarification; Flight Crew Took Evasive Action
Human Factors; Procedure
Aircraft X was in my Tower pattern; making right traffic for Runway 17R. Aircraft Y was given left downwind for Runway 17R. I told Aircraft Y change to Runway 17L; Runway 17L clear to land; and he read it back. Aircraft X was on a 2-mile final when Aircraft Y turned base. I gave Aircraft Y; traffic 2-mile final; Aircraft X; for the parallel runway. Aircraft Y said; I thought I was cleared to Runway 17R. I said negative; Runway 17L cleared to land. At the time Aircraft X took evasive maneuvers. Aircraft Y landed on the right and Aircraft X said we are on the go with that near miss. Aircraft Y was given possible pilot deviation. I'm not sure anything could have been done different from a Controller stand point. Aircraft Y was cleared to land Runway 17L and he read it back. It was a pilot deviation.
A Tower Controller reported an aircraft turned base and lined up with the wrong runway; causing a NMAC with traffic on short final.