Aeronca Champion
Air Traffic Control Fully Certified
Situational Awareness; Communication Breakdown
ATC Issue All Types; Conflict Ground Conflict; Critical; Deviation / Discrepancy - Procedural Clearance; Ground Incursion Runway
Air Traffic Control Issued New Clearance
Human Factors
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.
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.