Narrative:

I entered a standard left upwind for runway 27 making position reports. A C172 announced he was inbound. I acknowledged I had him in sight. He radioed that he would come in behind me. I then scanned the downwind for other aircraft and observed none. I announced my crosswind turn. During the crosswind; I was scanning the downwind for other aircraft. Announced and made turn to downwind. While on downwind; I didn't observe any aircraft in front; on base or final. Continued to make position reports and normal down to base; and base to final turns. Just after completing my base to final turn; I heard the C172 report downwind and that he had both of us in sight. I immediately looked to the sides; then down; to observe a cessna passing me about 75 ft below. I executed a go around. The cessna continued to land normally. After landing; I spoke to the C172 pilot. He said prior to his radio call he had not heard any position or intention xmissions from the cessna. I believe the cessna was making a straight-in approach with an inoperable radio. For my part; I should have been scanning beyond the normal base and final pattern for other aircraft.

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Original NASA ASRS Text

Title: EXPERIMENTAL ACFT EXPERIENCES NMAC WITH AN UNSPECIFIED CESSNA WHILE TURNING TO FINAL AT A NON-TOWERED ARPT.

Narrative: I ENTERED A STANDARD L UPWIND FOR RWY 27 MAKING POS RPTS. A C172 ANNOUNCED HE WAS INBOUND. I ACKNOWLEDGED I HAD HIM IN SIGHT. HE RADIOED THAT HE WOULD COME IN BEHIND ME. I THEN SCANNED THE DOWNWIND FOR OTHER ACFT AND OBSERVED NONE. I ANNOUNCED MY XWIND TURN. DURING THE XWIND; I WAS SCANNING THE DOWNWIND FOR OTHER ACFT. ANNOUNCED AND MADE TURN TO DOWNWIND. WHILE ON DOWNWIND; I DIDN'T OBSERVE ANY ACFT IN FRONT; ON BASE OR FINAL. CONTINUED TO MAKE POS RPTS AND NORMAL DOWN TO BASE; AND BASE TO FINAL TURNS. JUST AFTER COMPLETING MY BASE TO FINAL TURN; I HEARD THE C172 RPT DOWNWIND AND THAT HE HAD BOTH OF US IN SIGHT. I IMMEDIATELY LOOKED TO THE SIDES; THEN DOWN; TO OBSERVE A CESSNA PASSING ME ABOUT 75 FT BELOW. I EXECUTED A GAR. THE CESSNA CONTINUED TO LAND NORMALLY. AFTER LNDG; I SPOKE TO THE C172 PLT. HE SAID PRIOR TO HIS RADIO CALL HE HAD NOT HEARD ANY POS OR INTENTION XMISSIONS FROM THE CESSNA. I BELIEVE THE CESSNA WAS MAKING A STRAIGHT-IN APCH WITH AN INOPERABLE RADIO. FOR MY PART; I SHOULD HAVE BEEN SCANNING BEYOND THE NORMAL BASE AND FINAL PATTERN FOR OTHER ACFT.

Data retrieved from NASA's ASRS site as of May 2009 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.