Narrative:

While on downwind making left closed traffic to runway 20 in a cessna 182 at the ZZZ airport; I heard another airplane; a grumman tiger; making radio calls about being ahead of us in the pattern. Not having seen the plane ahead of us; I announced our position on downwind and we began our descent from the position abeam the runway 20 numbers; and then turned base both diagonal to the touchdown zone and approximately 800 feet AGL. During the base leg; the student I was training had improperly trimmed the airplane causing excessive rate of descent. I was subsequently distracted while instructing the student to correct the untrimmed condition; and did not announce my position on the base leg. During this time; I had assumed the grumman who had announced their position well ahead of us in the pattern had already continued to land. However; the grumman had actually flown what I believe was an excessively wide pattern and extended downwind leg outside of the pattern we had flown; and therefore was still on long final approach to runway 20 as we descended on the base leg. Our flight paths therefore converged as we began the turn to final at approximately 500 feet AGL; with the grumman just passing in front of and above our cessna 182. I promptly identified my location and began a climb to go-around above the grumman while it finished the descent to landing. It seems that the grumman had not seen us turning from base-to-final just below their altitude; possibly due to the low-wing of the plane; and I had not seen them due to the high-wing of the cessna 182 blocking the view of the final approach leg above me. We also heard no calls from the grumman about turning onto an extended long final approach. In the end; we both were able to diverge in time; and I gave way to the grumman who was already descending on final approach; despite my having been lower and closer to the runway on base leg. Nevertheless; next time I will be sure to announce my position clearly on each leg of the traffic pattern; and to be aware of other aircraft flying wide and long traffic patterns so that I can better sequence myself behind such traffic.

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Original NASA ASRS Text

Title: C182 flight instructor reported a near miss with another aircraft while in the traffic pattern at an non-towered airport.

Narrative: While on downwind making left closed traffic to Runway 20 in a Cessna 182 at the ZZZ airport; I heard another airplane; a Grumman Tiger; making radio calls about being ahead of us in the pattern. Not having seen the plane ahead of us; I announced our position on downwind and we began our descent from the position abeam the Runway 20 numbers; and then turned base both diagonal to the touchdown zone and approximately 800 feet AGL. During the base leg; the student I was training had improperly trimmed the airplane causing excessive rate of descent. I was subsequently distracted while instructing the student to correct the untrimmed condition; and did not announce my position on the base leg. During this time; I had assumed the Grumman who had announced their position well ahead of us in the pattern had already continued to land. However; the Grumman had actually flown what I believe was an excessively wide pattern and extended downwind leg outside of the pattern we had flown; and therefore was still on long final approach to Runway 20 as we descended on the base leg. Our flight paths therefore converged as we began the turn to final at approximately 500 feet AGL; with the Grumman just passing in front of and above our Cessna 182. I promptly identified my location and began a climb to go-around above the Grumman while it finished the descent to landing. It seems that the Grumman had not seen us turning from base-to-final just below their altitude; possibly due to the low-wing of the plane; and I had not seen them due to the high-wing of the Cessna 182 blocking the view of the final approach leg above me. We also heard no calls from the Grumman about turning onto an extended long final approach. In the end; we both were able to diverge in time; and I gave way to the Grumman who was already descending on final approach; despite my having been lower and closer to the runway on base leg. Nevertheless; next time I will be sure to announce my position clearly on each leg of the traffic pattern; and to be aware of other aircraft flying wide and long traffic patterns so that I can better sequence myself behind such traffic.

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.