MULTIPLE RWY OP PARALLEL RWYS ACR X TCASII RA WITH ACFT ON PARALLEL RWY OVERTOOK TFC AND MADE GAR.

Narrative

ACR X WAS FLYING THE CIVET PROFILE DSCNT TO RWY 25L. WE WERE CLRED ILS RWY 25L AFTER ARNES. APCH CTL POINTED OUT A COMMUTER ACFT Y AT 10 O'CLOCK WHICH WOULD PASS BEHIND AND GO TO THE R SIDE. WE ACKNOWLEDGED THE TFC IN SIGHT AND THOUGHT THEY WOULD GO TO THE RWY 24 COMPLEX. APCH CTL POINTED OUT TFC AT 11 O'CLOCK FOR US TO FOLLOW TO RWY 25L. WE RPTED IT IN SIGHT AND WERE CLRED VISUAL APCH TO RWY 25L. THE COMMUTER ACFT PASSED BEHIND US AND NOW WAS CLRED VISUAL APCH RWY 25R. OUR TCASII BEGAN RA'S; 1500 FPM DSCNT; ALL THE WAY DOWN FINAL APCH. I GLANCED OUT THE FO'S SIDE WINDOW AND SAW THE COMMUTER ALMOST ABEAM US AND IT APPEARED LESS THAN 500 FT. IT REMAINED THERE DURING OUR APCH. WITH OUR HIGHER APCH SPD; WE CLOSED ON THE TFC AHEAD AND WHEN IT BECAME APPARENT IT WOULD NOT CLR RWY 25L IN TIME; WE EXECUTED A MISSED APCH. WE WERE VECTORED N OF LAX ARPT FOR A BASE LEG FOR RWY 24R; APCH CTL POINTED OUT TFC Z AT 10 O'CLOCK. WE RPTED IT IN SIGHT AND WERE TOLD TO FOLLOW THAT TFC Z. WE WERE CLRED VISUAL APCH RWY 24R AND THE TFC WOULD LAND RWY 24L. EVEN AFTER SLOWING TO APCH SPD WE ROLLED OUT ON FINAL APCH JUST OUTSIDE THE FINAL FIX AND LESS THAN 1 MI FROM OUR TFC Z AND 1000 FT ABOVE THE GS. AGAIN WE GOT RA'S ALL THE WAY DOWN FINAL APCH CALLING FOR A CLB. LAX APCH CTL MUST STOP VECTORING BASE LEGS FOR PARALLEL APCHS TO RWY 25L AND 25R AND PARALLEL APCHS TO RWY 24L AND 24R WITH UNSAFE LONGITUDINAL SPACING.