Narrative:

I went to the airport for the purpose of doing 4-6 takeoffs/lndgs to maintain my currency in an small aircraft xx. The first rental small aircraft xx to which I was assigned demonstrated a faulty right magneto on run-up and when learning failed to correct the problem, I returned to the FBO. I had to wait about an hour for another small aircraft xx to become available. I finally took off in the second aircraft, having advised tower that I would be staying in the pattern for takeoff and lndgs. Runways 9L and 9R were in use and I was assigned 9L. On my first go around I was cleared for a touch and go on 9L and heard tower clear another aircraft for landing on 9R. I had the other aircraft, an small aircraft xy, in sight. While on base leg, I watched the small aircraft xy turn base to final. I then turned base and also reached down and pulled the third notch of flaps and also did a quick panel scan. I then looked outside again for runway alignment. I mistakenly fixed on the threshold marks for 9R and pulled the aircraft over to line up. As I did so I suddenly noticed the small aircraft xy below me at about 1:30. I immediately advised tower that I was aborting the landing and would go around. That maneuver was accomplished. Solution: keep your eyes outside the cockpit on final, particularly when running with parallel traffic and keep your assumed runway in sight at all times.

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Original NASA ASRS Text

Title: NMAC OCCURRED IN TARFFIC PATTERN BETWEEN 2 ARRIVING SMA CATEGORY ACFT.

Narrative: I WENT TO THE ARPT FOR THE PURPOSE OF DOING 4-6 TKOFS/LNDGS TO MAINTAIN MY CURRENCY IN AN SMA XX. THE FIRST RENTAL SMA XX TO WHICH I WAS ASSIGNED DEMONSTRATED A FAULTY RIGHT MAGNETO ON RUN-UP AND WHEN LEARNING FAILED TO CORRECT THE PROB, I RETURNED TO THE FBO. I HAD TO WAIT ABOUT AN HR FOR ANOTHER SMA XX TO BECOME AVAILABLE. I FINALLY TOOK OFF IN THE SECOND ACFT, HAVING ADVISED TWR THAT I WOULD BE STAYING IN THE PATTERN FOR TKOF AND LNDGS. RWYS 9L AND 9R WERE IN USE AND I WAS ASSIGNED 9L. ON MY FIRST GAR I WAS CLRED FOR A TOUCH AND GO ON 9L AND HEARD TWR CLR ANOTHER ACFT FOR LNDG ON 9R. I HAD THE OTHER ACFT, AN SMA XY, IN SIGHT. WHILE ON BASE LEG, I WATCHED THE SMA XY TURN BASE TO FINAL. I THEN TURNED BASE AND ALSO REACHED DOWN AND PULLED THE THIRD NOTCH OF FLAPS AND ALSO DID A QUICK PANEL SCAN. I THEN LOOKED OUTSIDE AGAIN FOR RWY ALIGNMENT. I MISTAKENLY FIXED ON THE THRESHOLD MARKS FOR 9R AND PULLED THE ACFT OVER TO LINE UP. AS I DID SO I SUDDENLY NOTICED THE SMA XY BELOW ME AT ABOUT 1:30. I IMMEDIATELY ADVISED TWR THAT I WAS ABORTING THE LNDG AND WOULD GO AROUND. THAT MANEUVER WAS ACCOMPLISHED. SOLUTION: KEEP YOUR EYES OUTSIDE THE COCKPIT ON FINAL, PARTICULARLY WHEN RUNNING WITH PARALLEL TFC AND KEEP YOUR ASSUMED RWY IN SIGHT AT ALL TIMES.

Data retrieved from NASA's ASRS site as of August 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.