Narrative:

On IFR flight plan in VMC, 10 NM north of esn, canceled IFR. Descended from 6000 ft cruise to 2000 ft approach altitude. Unicom 'runway 22R traffic.' circled south of airport, joined right downwind for runway 22. Other traffic in pattern. Extended downwind with position calls (6 of them) at appropriate intervals, including right base to final. When on right base, saw other aircraft on left base quite high. Position call. Turned final well clear of left base traffic overhead. Called short final. Left base traffic passed overhead and turned right clear of pattern. Other traffic ahead on final too slow. Initiated right go around, right base and final with normal landing. Aircraft on left base passed about 200 ft overhead in right turn. No further view of other aircraft. My landing normal. Other traffic disregarded unicom/ATIS NOTAM to use right traffic on runway 22.

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Original NASA ASRS Text

Title: SMA PLT AND AN SMA ACFT HAD AN NMAC WHILE ENTERING THE TFC PATTERN FOR RWY 22 AT ESN.

Narrative: ON IFR FLT PLAN IN VMC, 10 NM N OF ESN, CANCELED IFR. DSNDED FROM 6000 FT CRUISE TO 2000 FT APCH ALT. UNICOM 'RWY 22R TFC.' CIRCLED S OF ARPT, JOINED R DOWNWIND FOR RWY 22. OTHER TFC IN PATTERN. EXTENDED DOWNWIND WITH POS CALLS (6 OF THEM) AT APPROPRIATE INTERVALS, INCLUDING R BASE TO FINAL. WHEN ON R BASE, SAW OTHER ACFT ON L BASE QUITE HIGH. POS CALL. TURNED FINAL WELL CLR OF L BASE TFC OVERHEAD. CALLED SHORT FINAL. L BASE TFC PASSED OVERHEAD AND TURNED R CLR OF PATTERN. OTHER TFC AHEAD ON FINAL TOO SLOW. INITIATED R GAR, R BASE AND FINAL WITH NORMAL LNDG. ACFT ON L BASE PASSED ABOUT 200 FT OVERHEAD IN R TURN. NO FURTHER VIEW OF OTHER ACFT. MY LNDG NORMAL. OTHER TFC DISREGARDED UNICOM/ATIS NOTAM TO USE R TFC ON RWY 22.

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.