FLC OF AN MLG OBSERVED AND FOLLOWED THE WRONG TFC DURING A VISUAL APCH RESULTING IN ATC INTERVENTION AND ISSUANCE OF NEW INSTRUCTIONS.

Narrative

WE HAD JUST EXECUTED A MISSED APCH DUE TO AN ACFT NOT CLRING THE RWY. THE FO; WHO WAS FLYING; HAD LESS THAN 100 HRS IN THE ACFT (FIRST MONTH ON THE LINE). I WAS TALKING HIM THROUGH THE MAP PROC AND COMMUNICATING WITH BAY TRACON FOR ANOTHER APCH. BAY VECTORED US TO THE DOWNWIND AND POINTED OUT AN ACFT ON FINAL THAT WE WERE TO FOLLOW. I ACKNOWLEDGED THE TFC (AT LEAST WHAT I THOUGHT WAS THE TFC!) I POINTED THE AIRPLANE OUT TO THE FO WHO BEGAN A TURN IN ON THE BASE. AS WE WERE ESTABLISHED ON BASE ANOTHER ACFT CAME ON RADIO AND SAID WE WERE TURNING BEHIND THE WRONG ACFT. AT THIS TIME WE GOT A TCASII RA AND A TA FROM APCH. I DID NOT SEE ACFT BUT SAW THE CONFLICT ON THE TCASII. THE ACFT WAS 500 FT BELOW US SO WE MAINTAINED OUR ASSIGNED ALT OF 2500 FT AND TURNED AWAY FROM THE FINAL APCH COURSE. WE EXECUTED A 360 DEG TURN AND REENTERED THE FINAL FOR AN UNEVENTFUL LNDG. THIS WAS DEFINITELY A CASE OF PLT OVERLOAD; MINE! THE NEWNESS OF THE FO COUPLED WITH THE DEMANDS OF RECONFIGURING THE ACFT FOR ANOTHER APCH; COMMUNICATING WITH ATC AND ENSURING THE FO HAD EVERYTHING 'TOGETHER' LED TO PLAIN OLE' OVERLOAD. A SIMPLE MISIDENT OF AN ACFT POTENTIALLY LED TO A SERIOUS ACCIDENT. THIS WAS A CLASSIC CASE OF A 'CHAIN-OF-EVENTS' TYPE SCENARIO. I DON'T KNOW WHAT I COULD HAVE DONE DIFFERENTLY TO CHANGE THE OUTCOME. CHALK THIS ONE UP TO DUMB LUCK.