Narrative:

After concluding the section of the flight away from the airport we were inbound to ZZZ in order to practice take off and landings. The airport was busier than normal due to a fly in lunch being held at the FBO. After the first lap in the traffic pattern to a full stop; we back taxied down runway xx in order to take off again. We took off runway xx announcing over the radios we would be departing runway xx in order to stay in the traffic pattern. On initial climb-out there were other aircraft announcing they were inbound to the airport and would be joining the downwind. We made initial visual contact with the aircraft utilizing the radios to remain an appropriate distance away. We turned crosswind and did not see any traffic in the area that would have caused us to extend our upwind leg. As we were on the crosswind we cleared the turn to the left and announced we were turning downwind for runway xx. As we were turning downwind; I looked out the right side of the aircraft to see another aircraft who I had not seen previously in the pattern; and who had not been announcing their position in the pattern; was entering the downwind straight in; rather than at a 45 degree angle. After making visual contact with the airplane I began evasive action by applying full power and starting a climbing right turn to avoid the traffic. After climbing away from the traffic; I announced on the radio that we were executing a right 360 degree turn for spacing for traffic on the downwind. At this time the aircraft we had avoided began announcing their position on the downwind; setting up to land runway xx. Following the incident we maintained visual separation and reported our position in the pattern via the radios and came in for a landing to a full stop on runway xx and taxied back to the FBO.

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Original NASA ASRS Text

Title: DA-20 Flight Instructor reported near mid-air collision with another aircraft while conducting flight training.

Narrative: After concluding the section of the flight away from the airport we were inbound to ZZZ in order to practice take off and landings. The airport was busier than normal due to a fly in lunch being held at the FBO. After the first lap in the traffic pattern to a full stop; we back taxied down Runway XX in order to take off again. We took off Runway XX announcing over the radios we would be departing Runway XX in order to stay in the traffic pattern. On initial climb-out there were other aircraft announcing they were inbound to the airport and would be joining the downwind. We made initial visual contact with the aircraft utilizing the radios to remain an appropriate distance away. We turned crosswind and did not see any traffic in the area that would have caused us to extend our upwind leg. As we were on the crosswind we cleared the turn to the left and announced we were turning downwind for Runway XX. As we were turning downwind; I looked out the right side of the aircraft to see another aircraft who I had not seen previously in the pattern; and who had not been announcing their position in the pattern; was entering the downwind straight in; rather than at a 45 degree angle. After making visual contact with the airplane I began evasive action by applying full power and starting a climbing right turn to avoid the traffic. After climbing away from the traffic; I announced on the radio that we were executing a right 360 degree turn for spacing for traffic on the downwind. At this time the aircraft we had avoided began announcing their position on the downwind; setting up to land Runway XX. Following the incident we maintained visual separation and reported our position in the pattern via the radios and came in for a landing to a full stop on Runway XX and taxied back to the FBO.

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.