Narrative:

Cessna was on right base cleared to land runway 25R; I heard a champ call for a left crosswind departure from runway 25L; I cleared the champ for departure from runway 25L approving the left crosswind departure. I noticed the champ departing runway 25R ; I sent the cessna around; the champ stopped his takeoff roll; I then cleared the champ for an intersection departure from runway 25R.

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Original NASA ASRS Text

Title: Tower Controller described a potential conflict event between traffic cleared to land Runway 25R and traffic cleared off Runway 25L; but in fact was initiating a departure from Runway 25R that resulted in a go around and an aborted takeoff.

Narrative: Cessna was on right base cleared to land Runway 25R; I heard a Champ call for a left crosswind departure from Runway 25L; I cleared the Champ for departure from Runway 25L approving the left crosswind departure. I noticed the Champ departing Runway 25R ; I sent the Cessna around; the Champ stopped his takeoff roll; I then cleared the Champ for an intersection departure from Runway 25R.

Data retrieved from NASA's ASRS site as of July 2013 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.