Narrative:

Approaching mdw from the east; controller vectored me over airport center then left pattern to runway 31L. I used exceptional caution and also confirmed with student pilot passenger that we were lined up with runway 31L. Runway markings for runway 31C were obscured by tire rubber. The upper right; top portion of the letter 'C' in 'runway 31C' needs repaint. Tower advised me that I had landed on runway 31C; other landing traffic was not affected.

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Original NASA ASRS Text

Title: A PILOT LANDED ON MDW'S RWY 31C IN VMC CONDITIONS WHEN CLEARED TO LAND ON RWY 31L. TIRE RUBBER OBSCURED THE UPPER PORTION OF THE C MAKING IT LOOK LIKE A L.

Narrative: APCHING MDW FROM THE E; CTLR VECTORED ME OVER ARPT CTR THEN L PATTERN TO RWY 31L. I USED EXCEPTIONAL CAUTION AND ALSO CONFIRMED WITH STUDENT PLT PAX THAT WE WERE LINED UP WITH RWY 31L. RWY MARKINGS FOR RWY 31C WERE OBSCURED BY TIRE RUBBER. THE UPPER R; TOP PORTION OF THE LETTER 'C' IN 'RWY 31C' NEEDS REPAINT. TWR ADVISED ME THAT I HAD LANDED ON RWY 31C; OTHER LNDG TFC WAS NOT AFFECTED.

Data retrieved from NASA's ASRS site as of May 2009 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.