A PA22 PLT ENTERING RWY 28R PATTERN; AT MRY SIGHTS ISSUED TFC; BUT HAS AN NMAC WITH A SECOND ACFT NOT ISSUED AS TFC.

Narrative

FOLLOWING PRACTICE AIR WORK OVERWATER NW OF MONTEREY; CA; REQUESTED VFR TO MRY FROM NORCAL APCH AND WAS GRANTED DIRECT TO ARPT; EXPECT R DOWNWIND RWY 28R. NORCAL SWITCHED US TO TWR APPROX 5 NM NW OF MRY; OVERWATER AND ON APPROX 45 DEGS TO R DOWNWIND RWY 28R. ONCE ON TWR FREQ; WAS ADVISED OF CHEROKEE IN MY 10-11 O'CLOCK POS. LOCATED CHEROKEE AND KEPT HIM IN SIGHT. TWR FREQ WAS EXTREMELY BUSY; AND HEARD TWR ADVISING A BONANZA OF SAME CHEROKEE TFC; PLUS ME IN HIS 12 O'CLOCK POS. I LOOKED TO MY R AND OBSERVED BEECH BONANZA LESS THAN 100 YARDS TO MY R; ON COLLISION COURSE; SLIGHTLY BELOW ME. I YANKED UP ON CTLS JUST AS HE PASSED UNDER ME LESS THAN 50 FT VERT; ZERO HORIZ. MY ALT WAS APPROX 2000 FT MSL. BONANZA MADE RADIO CALL: 'THAT WAS LESS THAN 100 FT.' ON GND; I FILED NMAC WITH TWR. FAA COMPLETED INVESTIGATION AND FOUND NO ONE AT FAULT. CONTRIBUTING FACTORS: 1) MRY TWR USUALLY IS UNDERSTAFFED AND 1 CTLR WORKS SEVERAL FREQS SIMULTANEOUSLY. 2) THIS WAS A VERY CLR; WARM DAY; CONTRIBUTING TO HIGH VOLUME OF VFR TFC (ALSO A WKEND DAY). 3) NAVY FA18 HORNET WAS TAXIING FOR TKOF AT TIME OF INCIDENT; CREATING DISTR ON AIRFIELD (RARE OCCURRENCE). 4) POSSIBLY -- POOR COORD BTWN NORCAL AND TWR REGARDING VFR INBOUND/OUTBOUND SEPARATION/PLANNING.