ACR FLC FLYING BAE3100 TO IAD FLEW THROUGH THE LOC COURSE WHILE BEING VECTORED AND SUBSEQUENTLY RECEIVED AN RA FROM THEIR TCASII.

Narrative

45 MI N OF DULLES; WE WERE TOLD TO MAINTAIN 230 KTS OR GREATER AND WE WERE FOLLOWING A HVY AIRBUS. ATIS WAS CALLING 6000 FT SCATTERED; 10 MI VISIBILITY. ACTUAL WAS 4000 FT OVCST; 4 MI VISIBILITY. WE BRIEFED A VISUAL APCH TO RWY 19R. APCH VECTORED US THROUGH THE LOC TO THE W; THEN TURNED US BACK AT A 90 DEG INTERCEPT. TA WAS RECEIVED AS LOC WAS ALIVE AND TFC ALERT FROM OUR TCASII ACTIVATED. APCH GAVE US NEW HDG TO REINTERCEPT RWY 19R LOC TO THE W AND STATED THE LOC FREQ FOR RWY 19R. WE TURNED BACK AND INTERCEPTED RWY 19R. DUE TO LATE TURN TO A LOC AND HIGH SPD REQUIRED AND TFC CONFLICT; OUR ATTN WAS DISTR AND WE PASSED THROUGH THE LOC. POSSIBLE CONFUSION OCCURRED WHEN THE PNF READ BACK RWY 19L IN CLRNC AND PUT IT IN ONE OF THE RADIOS. THE RWY 19L LOC WAS NEVER INTERCEPTED AND NO PENETRATION OF RWY 19L FLT PATH WAS ENCOUNTERED. POSSIBLE SOLUTION TO PROB IS TO REDUCE INTERCEPTION ANGLE BELOW 90 DEGS/SLOW SPD TO 170 KTS AND EARLY ALERT ON POSSIBLE CONFLICTING TFC BELOW. ALSO; ATIS SHOULD HAVE DEPICTED WX AS MUCH LOWER THAN 6000 FT SCATTERED 10 MI.