ACR FLC INTERCEPTED AND FLEW THE WRONG LOC COURSE. PARALLEL RWYS. ATCT CTLR INTERVENED.

Narrative

WHILE FLYING A SCHEDULED ACR FLT FROM BWI TO CLT; WE HAD DSNDED TO 3600 FT AND WERE TOLD TO EXPECT AN APCH TO RWY 36R AT CLT. I WAS FLYING THE ACFT (AN MD80) AS CAPT AND BRIEFED AN APCH TO RWY 36L BY MISTAKE. I BELIEVE THE MISTAKE WAS MADE WHEN I LEFT THE PROPER APCH PAGE FOR RWY 36R TO CONSULT THE LAND AND HOLD SHORT LENGTH FOR RWY 36R. WHEN I RETURNED TO BRIEF THE APCH; I WENT TO THE APCH PAGE FOR RWY 36L AND BRIEFED THE LOC AND COURSE AND MINIMUMS ASSOCIATED WITH IT. WHEN CLRED TO A HDG TO INTERCEPT THE LOC AND FLY THE ILS TO RWY 36R; I TURNED TO THE ASSIGNED HDG 330 DEGS AND FLEW THROUGH THE LOC FOR RWY 36R AND INTERCEPTED THE LOC FOR RWY 36L. ABOUT THE SAME TIME I NOTICED AN ACFT (ON THE TCASII) AT 1200 FT ABOVE US; THE CTLR INSTRUCTED US TO TURN R 30 DEGS TO INTERCEPT THE RWY 36R LOC INSTEAD OF THE RWY 36L LOC. WE COMPLIED WITH THE CTLR'S INSTRUCTIONS; TUNED IN THE PROPER LOC COURSE AND FREQ FOR RWY 36R AND FLEW AN UNEVENTFUL APCH. IT SHOULD BE NOTED THAT THE FO'S NAV INSTS WERE STILL IN CLT VOR 115.0 SO WE COULD HAVE DME DURING THE APCH. HE DID NOT NOTICE THAT I HAD THE WRONG LOC FREQ TUNED IN. ON TALKING TO THE CLT APCH CTLRS AFTER LNDG; I APOLOGIZED FOR MY ERROR AND COMMENDED THEM FOR THEIR HANDLING OF THE SIT. ALL ATC SEPARATION CRITERIA WAS MET AND THE ACFT ABOVE US NEVER DSNDED TO LESS THAN 1000 FT ABOVE US DURING THIS EVENT.