Narrative:

Aircraft X was doing full stop taxi backs for student practice. He departed runway 30R and I instructed him to make right traffic. Then I observed the aircraft turning for left traffic; and pointed out another aircraft that was in left traffic. Then I cleared aircraft X to land on runway 30R. I became busy dealing with other traffic and coordination; but checked on the progress of aircraft X and saw that he turned final for runway 30R.I dealt with a few other traffic situations then looked for aircraft X where he should be; just landing on runway 30R. Instead I observed the aircraft about to touch down on runway 30L. The other aircraft in the pattern had departed and it didn't affect anyone else; so I decided the safest action was to allow aircraft X to land on the wrong runway.the pilot involved was obviously inexperienced and unfamiliar with the airport and control procedures. I thought that I was providing enough extra information and simple enough instructions so as not to confuse the pilot; but evidently he needed even more hand holding than I was providing.

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Original NASA ASRS Text

Title: Controller report aircraft turning wrong direction to enter the pattern. Controller lets aircraft continue and changes the aircraft runway. Controller gets busy and then notices aircraft landing on wrong runway.

Narrative: Aircraft X was doing full stop taxi backs for student practice. He departed Runway 30R and I instructed him to make right traffic. Then I observed the aircraft turning for left traffic; and pointed out another aircraft that was in left traffic. Then I cleared aircraft X to land on Runway 30R. I became busy dealing with other traffic and coordination; but checked on the progress of aircraft X and saw that he turned final for Runway 30R.I dealt with a few other traffic situations then looked for aircraft X where he should be; just landing on Runway 30R. Instead I observed the aircraft about to touch down on Runway 30L. The other aircraft in the pattern had departed and it didn't affect anyone else; so I decided the safest action was to allow aircraft X to land on the wrong runway.The pilot involved was obviously inexperienced and unfamiliar with the airport and control procedures. I thought that I was providing enough extra information and simple enough instructions so as not to confuse the pilot; but evidently he needed even more hand holding than I was providing.

Data retrieved from NASA's ASRS site 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.