GA8 PILOT REPORTS CRITICAL CONFLICT WITH TWO OTHER ACFT IN TRAFFIC PATTERN AT UNCONTROLLED ARPT.

Narrative

IT WAS A TYPICAL FIRST DAY OF SPRING FLYING. THERE WAS PLENTY OF RADIO TFC ON THE CTAF (USED BY SEVERAL ARPTS). I WAS RELEASED FROM APCH TO ADVISORY FREQ 4 MI S AT 3500 FT. I ANNOUNCED MY POS AND REQUESTED ADVISORIES ON THE CTAF. I SPOTTED AN AIRPLANE ON THE RWY AND HEARD A MOONEY WHO ANNOUNCED SEVERAL MI TO THE W OF THE ARPT. I ANNOUNCED MY ENTRY TO THE DOWNWIND AT ABOUT 2 MI AND 2000 FT MSL (PATTERN ALT 1800 FT MSL). THE MOONEY WAS SPOTTED AT MY 9 O'CLOCK POS. HE ANNOUNCED A DOWNWIND ENTRY AND THE SMALL TAIL DRAGGER THAT WAS ON THE RWY WAS XWIND TO DOWNWIND. SO; THE SE CORNER OF THE PATTERN HAD 3 ACFT WITHIN 500 FT OF EACH OTHER. I ANNOUNCED THAT THERE WERE 3 ACFT STACKED ON TOP OF EACH OTHER IN THE DOWNWIND. A FOURTH PLT ACKNOWLEDGED WITNESSING THE EVENT. THE TAIL DRAGGER DEPARTED; DIRECTION UNKNOWN. I MANEUVERED EASTWARD PAST THE FREEWAY HDG N AND DSNDING TO ABOUT 1000 FT MSL. THE MOONEY CONTINUED HIS APCH. WE WERE FLYING PARALLEL IN THE DOWNWIND. I WAS OUTSIDE; HE WAS INSIDE THE PATTERN. THE MOONEY LANDED; I EXTENDED MY DOWNWIND TO PROVIDE SEPARATION AND LANDED WITHOUT INCIDENT.