Narrative:

On right downwind for runway 13 a piper seneca that had departed after us flew about 100 ft over us. We noticed the traffic at the last second and pitched down to avoid a collision. The piper had turned early from the upwind leg during their departure to the south and that put them on a collision course with our aircraft flying downwind. We did not receive any traffic alerts from tower. When I asked tower why we didn't receive any alert he said that the radar track showed them passing behind us.

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Original NASA ASRS Text

Title: A DA20 instructor pilot and his student in the traffic pattern experienced an NMAC with a Piper Seneca that had taken off after them but passed overhead 100 FT while on downwind.

Narrative: On right downwind for Runway 13 a Piper Seneca that had departed after us flew about 100 FT over us. We noticed the traffic at the last second and pitched down to avoid a collision. The Piper had turned early from the upwind leg during their departure to the south and that put them on a collision course with our aircraft flying downwind. We did not receive any traffic alerts from Tower. When I asked Tower why we didn't receive any alert he said that the radar track showed them passing behind us.

Data retrieved from NASA's ASRS site as of July 2013 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.