CLOSE PROX ACR-MLG GA-SMA E OF SFO.

Narrative

DSNDING INTO SFO; THE EVENT WAS A NEAR MISS WITH A SMALL; GA SINGLE ENG; LOW WING ACFT WITH SMALL TIP TANKS. SFO APCH CTL CLRED US TO LEAVE 11000 FT AND DSND TO 7000 FT. AT APPROX 9700 FT OR 9600 FT THE CTLR CALLED TFC AT 2 O'CLOCK; 1 MI; INDICATING 9500 FT. AT THIS TIME WE WERE PASSING 9700 FT TO 9600 FT. I LOOKED TO 2 O'CLOCK AND SAW THE ABOVE DESCRIBED ACFT AT A RANGE OF APPROX 1/2 MI. WE WERE DSNDING AT APPROX 1500 TO 1700 FPM; BUT WE PULLED UP INTO A CLB AND PASSED APPROX 250-300 FT AHEAD OF AND ABOVE THE INTRUDER ACFT. THE ACFT WAS RETURNED TO A DSCNT AND PROCEEDED TO LAND IN SFO INTL. MY ACFT DID HAVE TCAS INSTALLED; BUT IT WAS INOPERATIVE AT THE TIME. SOLUTIONS OR SUGGESTIONS: MORE REQUIRED TCAS FOR ALL ACFT OPERATING IN OR NEAR ARPTS. PUBLISH WARNING ZONES FOR CERTAIN AREAS (DSCNT CORRIDORS) AND ALTS AROUND THE EDGES OF TCA (OR ENLARGE THE TCA). REQUIRE ALL ACFT TO HAVE ALT RPTING TRANSPONDERS. UPDATE ALL ATC FACILITIES WITH 'STATE-OF- THE-ART' RADAR AND COMPUTERS. BETTER COORD BTWN 'CENTER' AND 'APCH CTL/TWR.'