Narrative:

My student and I entered the r-hand traffic pattern on the downwind for runway 14. We were cleared to land by tower abeam midfield. We continued on our normal approach to landing. I have instructed my students to look for traffic prior to any turn, especially in the pattern, because even in a 'controled' environment, airplanes can show up anywhere! On base, small aircraft X checked final and left downwind for other traffic. It was clear so we turned final. After we were established on final, another aircraft reported entering left downwind. Tower cleared him to land. At this point we were on 3/4 mi final. The other aircraft looked like it flew a short approach. He did not see us, and we did not see him. He came up behind us from the left, about 40-50 ft below us. Because he was a high wing small aircraft Y, he could not see us. We saw him about 100 ft (horizontally) before the threshold. At that same moment, tower instructed us both to go around. Both airplanes circled opposite directions and continued to land without incident. Afterwards, I talked to the controller about what had happened. He said he had gotten distracted and should have waited to clear the other aircraft or pointed out 'traffic short final.' the next day I talked to the tower manager.

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Original NASA ASRS Text

Title: SMA X HAD NMAC WITH SMA Y IN ATA. EVASIVE ACTION TAKEN. SEE AND AVOID CONCEPT.

Narrative: MY STUDENT AND I ENTERED THE R-HAND TFC PATTERN ON THE DOWNWIND FOR RWY 14. WE WERE CLRED TO LAND BY TWR ABEAM MIDFIELD. WE CONTINUED ON OUR NORMAL APCH TO LNDG. I HAVE INSTRUCTED MY STUDENTS TO LOOK FOR TFC PRIOR TO ANY TURN, ESPECIALLY IN THE PATTERN, BECAUSE EVEN IN A 'CTLED' ENVIRONMENT, AIRPLANES CAN SHOW UP ANYWHERE! ON BASE, SMA X CHKED FINAL AND L DOWNWIND FOR OTHER TFC. IT WAS CLR SO WE TURNED FINAL. AFTER WE WERE ESTABLISHED ON FINAL, ANOTHER ACFT RPTED ENTERING L DOWNWIND. TWR CLRED HIM TO LAND. AT THIS POINT WE WERE ON 3/4 MI FINAL. THE OTHER ACFT LOOKED LIKE IT FLEW A SHORT APCH. HE DID NOT SEE US, AND WE DID NOT SEE HIM. HE CAME UP BEHIND US FROM THE L, ABOUT 40-50 FT BELOW US. BECAUSE HE WAS A HIGH WING SMA Y, HE COULD NOT SEE US. WE SAW HIM ABOUT 100 FT (HORIZLY) BEFORE THE THRESHOLD. AT THAT SAME MOMENT, TWR INSTRUCTED US BOTH TO GAR. BOTH AIRPLANES CIRCLED OPPOSITE DIRECTIONS AND CONTINUED TO LAND WITHOUT INCIDENT. AFTERWARDS, I TALKED TO THE CTLR ABOUT WHAT HAD HAPPENED. HE SAID HE HAD GOTTEN DISTRACTED AND SHOULD HAVE WAITED TO CLR THE OTHER ACFT OR POINTED OUT 'TFC SHORT FINAL.' THE NEXT DAY I TALKED TO THE TWR MGR.

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