Narrative:

Small transport X requested visual approach to runway 23. Approach controller issued 'unable, cleared visual approach runway 29.' pilot acknowledged. Small transport X advised to switch to tower frequency. Tower (local) issued 'cleared to land runway 29.' pilot acknowledged. Small transport X continued through final (runway 29) entered left base for runway 23. Passed under small aircraft Y on right downwind for runway 29. TA was issued to both aircraft. Directional guidance was issued to small transport X to turn back to correct runway. Small transport X landed runway 29. I estimate small transport X passed within 100 ft of small aircraft Y.

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Original NASA ASRS Text

Title: SMT X VISUAL APCH TO WRONG RWY HAD NMAC WITH SMA Y. SEE AND AVOID CONCEPT.

Narrative: SMT X REQUESTED VISUAL APCH TO RWY 23. APCH CTLR ISSUED 'UNABLE, CLRED VISUAL APCH RWY 29.' PLT ACKNOWLEDGED. SMT X ADVISED TO SWITCH TO TWR FREQ. TWR (LCL) ISSUED 'CLRED TO LAND RWY 29.' PLT ACKNOWLEDGED. SMT X CONTINUED THROUGH FINAL (RWY 29) ENTERED L BASE FOR RWY 23. PASSED UNDER SMA Y ON R DOWNWIND FOR RWY 29. TA WAS ISSUED TO BOTH ACFT. DIRECTIONAL GUIDANCE WAS ISSUED TO SMT X TO TURN BACK TO CORRECT RWY. SMT X LANDED RWY 29. I ESTIMATE SMT X PASSED WITHIN 100 FT OF SMA Y.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.