Narrative:

A friend and I were practicing landings in two cessna 150's. While doing pattern-work I was involved in a near mid-air collision. I was unaware at the time but my friend radios me over the in-flight 'team frequency' we use and questions if I saw the light twin. When we get on the ground I am informed that a white; t-tail; light twin (most likely a seminole) flew 200' directly over my aircraft while I was downwind at 1;000' AGL. The offending aircraft never made any radio traffic calls and did not attempt to enter the pattern after the incident. No evasive action was taken because no radio calls were made; being in a high-wing aircraft I could not see the twin's approach and flight overhead; and by the time I was warned of the situation the danger had passed. Both my friend and I had been making the proper radio calls for all pattern legs as it was a gorgeous day and we could hear much traffic at nearby airports.

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Original NASA ASRS Text

Title: C150 pilot was informed after the fact; that a light twin passed 200 FT above on the downwind leg. The twin was not observed by the reporter.

Narrative: A friend and I were practicing landings in two Cessna 150's. While doing pattern-work I was involved in a near mid-air collision. I was unaware at the time but my friend radios me over the in-flight 'team frequency' we use and questions if I saw the light twin. When we get on the ground I am informed that a white; T-tail; light twin (most likely a seminole) flew 200' directly over my aircraft while I was downwind at 1;000' AGL. The offending aircraft never made any radio traffic calls and did not attempt to enter the pattern after the incident. No evasive action was taken because no radio calls were made; being in a high-wing aircraft I could not see the twin's approach and flight overhead; and by the time I was warned of the situation the danger had passed. Both my friend and I had been making the proper radio calls for all pattern legs as it was a gorgeous day and we could hear much traffic at nearby airports.

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.