Narrative:

I was conducting a private pilot lesson with a student. We were flying a cessna 172. As always; I placed emphasis on looking outside for traffic in an effort to be as safe as possible. On our return the tower cleared us to make a straight in approach for runway 9L and to report three miles to the west. A tri-pacer was turning left base for 9L. He got cleared to land and we were instructed to follow him. I accepted the clearance to land and slowed to approach speed and conducted a before landing checklist.another aircraft; a piper seneca; was also on its way in to land and was instructed to look for cessna traffic on a 2.5 to three mile final. The seneca initially said he didn't have the traffic in sight; then immediately reported in sight and that he was number two for runway 9L. The traffic the seneca was supposed to be following was my C172 and he was actually number three for 9L.while on the runway centerline at approximately 300 to 400 AGL the seneca passed over my right wing and fuselage with its left wing and fuselage; missing my aircraft by ten to fifteen feet. The seneca continued descending to land on 9L and I immediately called tower to notify them that an aircraft had just passed overhead and that I needed to go around while taking over the flight controls from my student. I conducted a go-around and sidestepped to the left of the runway to avoid the tri-pacer that was now on the departure leg after a touch and go. The seneca conducted a go around as well and I told tower that I was going to start an early crosswind to avoid any further congestion within the pattern.we continued to climb in a left turn to join the left downwind for 9L. From there we conducted a normal landing on 9L then continued to do two more laps in the pattern to work on takeoffs and landings and ended our lesson. After the flight the student and I talked about the incident. I emphasized the importance of see-and-avoid as well as educated him to the dangers of high wing aircraft being below low wing aircraft.

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Original NASA ASRS Text

Title: An NMAC with a PA-34 on short final approach occurred when a PA-34 pilot mistook a prior arrival as the traffic they were to follow.

Narrative: I was conducting a private pilot lesson with a student. We were flying a Cessna 172. As always; I placed emphasis on looking outside for traffic in an effort to be as safe as possible. On our return the Tower cleared us to make a straight in approach for Runway 9L and to report three miles to the west. A Tri-Pacer was turning left base for 9L. He got cleared to land and we were instructed to follow him. I accepted the clearance to land and slowed to approach speed and conducted a before landing checklist.Another aircraft; a Piper Seneca; was also on its way in to land and was instructed to look for Cessna traffic on a 2.5 to three mile final. The Seneca initially said he didn't have the traffic in sight; then immediately reported in sight and that he was number two for Runway 9L. The traffic the Seneca was supposed to be following was my C172 and he was actually number three for 9L.While on the runway centerline at approximately 300 to 400 AGL the Seneca passed over my right wing and fuselage with its left wing and fuselage; missing my aircraft by ten to fifteen feet. The Seneca continued descending to land on 9L and I immediately called Tower to notify them that an aircraft had just passed overhead and that I needed to go around while taking over the flight controls from my student. I conducted a go-around and sidestepped to the left of the runway to avoid the Tri-pacer that was now on the departure leg after a touch and go. The Seneca conducted a go around as well and I told Tower that I was going to start an early crosswind to avoid any further congestion within the pattern.We continued to climb in a left turn to join the left downwind for 9L. From there we conducted a normal landing on 9L then continued to do two more laps in the pattern to work on takeoffs and landings and ended our lesson. After the flight the student and I talked about the incident. I emphasized the importance of see-and-avoid as well as educated him to the dangers of high wing aircraft being below low wing aircraft.

Data retrieved from NASA's ASRS site as of April 2012 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.