Narrative:

Approached the airport from southwest at 3000 123.6 CTAF for aas due to terrain was not available until I crossed eni VOR eastbound (7 southwest). CTAF had an small aircraft a and small aircraft B in pattern. The frequency was then used to discuss local WX for at least 3 mins. I reported to the east and that I had the numbers entered the 45 degree, more local chatter about conditions on CTAF. Downwind at 1600 ft an small aircraft C passed under me also on downwind about 300 ft beneath. Thinking he may be a local passing down the valley I asked what he was doing under me. I turned base and he turned base. I again asked what he was doing. He was sorry he didn't see me and was landing. I announced a 'go around' (I should have said 360 degree or 270, but this sounded more impressive). I did a left 270 turn. The small aircraft a had full stopped and small aircraft B was doing a touch and go. Rolling back in on close final the small aircraft C touched down, reversed course having missed his normal turn off. Small aircraft C taxiing back on the runway to better access his hangar area. The FSS operator told me (in person) 'he (small aircraft C) had reported in 4 mins earlier'. Was 'he' the one using CTAF gossiping about local rain expectation or was the FSS operator opening all switches including tying up 123.6 to report WX. Maybe he is just local friendly. But frequency misuse, low on pattern, turning around on an active runway. But I should not have announced 'going around' a maneuver that would have given the small aircraft C all the time necessary.

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Original NASA ASRS Text

Title: SMA IN TFC PATTERN HAS NMAC.

Narrative: APCHED THE ARPT FROM SW AT 3000 123.6 CTAF FOR AAS DUE TO TERRAIN WAS NOT AVAILABLE UNTIL I CROSSED ENI VOR EBOUND (7 SW). CTAF HAD AN SMA A AND SMA B IN PATTERN. THE FREQ WAS THEN USED TO DISCUSS LCL WX FOR AT LEAST 3 MINS. I RPTED TO THE E AND THAT I HAD THE NUMBERS ENTERED THE 45 DEG, MORE LCL CHATTER ABOUT CONDITIONS ON CTAF. DOWNWIND AT 1600 FT AN SMA C PASSED UNDER ME ALSO ON DOWNWIND ABOUT 300 FT BENEATH. THINKING HE MAY BE A LCL PASSING DOWN THE VALLEY I ASKED WHAT HE WAS DOING UNDER ME. I TURNED BASE AND HE TURNED BASE. I AGAIN ASKED WHAT HE WAS DOING. HE WAS SORRY HE DIDN'T SEE ME AND WAS LNDG. I ANNOUNCED A 'GO AROUND' (I SHOULD HAVE SAID 360 DEG OR 270, BUT THIS SOUNDED MORE IMPRESSIVE). I DID A L 270 TURN. THE SMA A HAD FULL STOPPED AND SMA B WAS DOING A TOUCH AND GO. ROLLING BACK IN ON CLOSE FINAL THE SMA C TOUCHED DOWN, REVERSED COURSE HAVING MISSED HIS NORMAL TURN OFF. SMA C TAXIING BACK ON THE RWY TO BETTER ACCESS HIS HANGAR AREA. THE FSS OPERATOR TOLD ME (IN PERSON) 'HE (SMA C) HAD RPTED IN 4 MINS EARLIER'. WAS 'HE' THE ONE USING CTAF GOSSIPING ABOUT LCL RAIN EXPECTATION OR WAS THE FSS OPERATOR OPENING ALL SWITCHES INCLUDING TYING UP 123.6 TO RPT WX. MAYBE HE IS JUST LCL FRIENDLY. BUT FREQ MISUSE, LOW ON PATTERN, TURNING AROUND ON AN ACTIVE RWY. BUT I SHOULD NOT HAVE ANNOUNCED 'GOING AROUND' A MANEUVER THAT WOULD HAVE GIVEN THE SMA C ALL THE TIME NECESSARY.

Data retrieved from NASA's ASRS site as of July 2007 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.