Narrative:

While coming in from the southwest tower gave us instructions to enter a right downwind runway xxr. For some reason in my brain it processed as left downwind runway xxr. While this was happening I was with a beginner student and was talking and explaining about procedures and checklist that needed to be done the whole time from 10 nm out till a half mile when the tower called to confirm that we were on a right downwind. Taking a break from talking to the student; I responded confirming that we were. After a few seconds I realized that we were indeed not and on a left downwind and immediately called tower and admitted the mistake. At this moment an aircraft on the departure called that they had to deviate. I noticed the plane and determined that we were not on a collision course. To my view the plane was 100 yards away 200-300 ft lower and traveling in the opposite direction not on a collision course. After the other plane called to deviate tower instructed us to turn left to enter the right downwind runway xxr after we had already passed the other plane.

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Original NASA ASRS Text

Title: PA28 flight instructor reported an NMAC resulted when he and his student flew a left pattern instead of the cleared right pattern.

Narrative: While coming in from the southwest Tower gave us instructions to enter a right downwind Runway XXR. For some reason in my brain it processed as left downwind Runway XXR. While this was happening I was with a beginner student and was talking and explaining about procedures and checklist that needed to be done the whole time from 10 nm out till a half mile when the tower called to confirm that we were on a right downwind. Taking a break from talking to the student; I responded confirming that we were. After a few seconds I realized that we were indeed not and on a left downwind and immediately called Tower and admitted the mistake. At this moment an aircraft on the departure called that they had to deviate. I noticed the plane and determined that we were not on a collision course. To my view the plane was 100 yards away 200-300 ft lower and traveling in the opposite direction not on a collision course. After the other plane called to deviate tower instructed us to turn left to enter the right downwind Runway XXR after we had already passed the other plane.

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.