FREQ CONFUSION RESULTED IN MISSED APCH FOR CL65 LNDG MEM.

Narrative

ACR X FLT FROM DFW TO MEM WAS CLRED TO LAND ON RWY 36L ON A FREQ OF 119.1. WE BROKE OUT OF THE CLOUDS AT 300 FT AGL; AND THERE WAS AN ACFT ON THE RWY JUST STARTING ITS TKOF ROLL. AT 200 FT (MINIMUMS) WE EXECUTED THE MISSED APCH (PUBLISHED) AND INFORMED TWR. TWR SEEMED CONFUSED ABOUT OUR LOCATION; AND IN LIEU OF ANY OTHER INSTRUCTIONS WE WERE STILL EXECUTING THE PUBLISHED MISSED APCH. WE WERE TOLD TO MAINTAIN 2000 FT; AND RETURN TO RWY HDG (360 DEGS). WE HAD TURNED TO A HDG OF 270 DEGS TO 300 DEGS L TO INTERCEPT THE 323 DEG RADIAL TO PROCEED TO OUR INTXN TO HOLD. THIS INSTRUCTION WAS A TURN IN THE OPPOSITE DIRECTION (R). THEN WE RECEIVED ANOTHER INSTRUCTION FROM THE TWR TO TURN TO 180 DEGS; THEN 190 DEGS; ANOTHER TURN IN THE OPPOSITE DIRECTION; AND TOLD TO CONTACT DEP. ACR X WAS VECTORED AROUND FOR ANOTHER APCH TO RWY 36L; AND LANDED WITH NO FURTHER PROBS. WHEN CALLING FOR CLRNC; WE WERE GIVEN A NUMBER TO CALL THE FAA TWR. I WAS XFERRED TO SEVERAL SUPVRS; WHO TOLD ME THEY WANTED TO ASK ME SOME QUESTIONS FOR AN INVESTIGATION. I DO NOT KNOW IF IT WAS RECORDED; BUT I FELT UNEASY ABOUT ANSWERING QUESTIONS WITHOUT ANY COUNSEL OR ADVISORS. I DID; HOWEVER; ANSWER THEIR QUESTIONS. THE SUPVR EXPLAINED HE HAD LISTENED TO THE TWR TAPES. IT APPEARS THEY SPLIT TWR FREQS AFTER WE HAD BEEN CLRED TO LAND. I CALLED ON THE FREQ THEY TOLD ME TO -- 119.7; BUT AFTER THEY SPLIT THE FREQS; THEN 119.7 WAS THE CORRECT FREQ FOR RWY 36C/36R. WHEN WE CALLED MISSED APCH; I WAS TALKING TO A CTLR; WHO WAS WORKING THE OTHER RWYS! THIS WAS THE CAUSE FOR THE DELAY IN INSTRUCTIONS. THE FAA SUPVR WANTED TO KNOW WHY WE DID WHAT WE DID. I SIMPLY EXPLAINED WE EXPECTED THE PUBLISHED MISSED APCH UNTIL GIVEN DIFFERENT INSTRUCTIONS. I EXPLAINED ALL THE SEQUENCE OF EVENTS I EXPLAINED HERE. HE APOLOGIZED FOR THE CONFUSION; AND WE HUNG UP WITH THE TELEPHONE CONVERSATION. I BELIEVE MY CREW DID NOTHING WRONG. I BELIEVE THE PROB WAS THE TIMING OF THE FREQ SPLIT; AND THE FACT THAT WE WERE NOT TOLD TO SWITCH TO THE APPROPRIATE FREQ FOR OUR SPECIFIC RWY 36L.