FLC OF AN LGT TOOK AN EVASIVE ACTION TURN FOR TCASII TFC. TA GIVEN. TFC NOT SIGHTED.

Narrative

ON OUR DSCNT INTO MELBOURNE FLORIDA ARPT; WE WERE HANDED OFF TO A CTLR AT PATRICK AFB. OUR ACFT WAS AT 2000 FT HDG SBOUND WHEN THE CTLR INFORMED US OF CESSNA 150 TFC AT 12 O'CLOCK AND A LITTLE BUT LOWER THAN WE WERE. WE STATED THAT WE WERE 'IMC;' DID NOT HAVE THE CESSNA VISUALLY; BUT HAD HIM ON OUR TCASII DISPLAY. (HE SHOWED UP INITIALLY AT 400 FT BELOW US AND DEAD AHEAD). THE CTLR THEN ASKED US IF WE HAD THE FIELD IN SIGHT. AGAIN; WE STATED THAT WE WERE 'IMC' AND DID NOT HAVE THE FIELD IN SIGHT. THE CTLR SEEMED CONFUSED THAT WE COULDN'T SEE THE FIELD! WE WERE CLOSING IN ON THE CESSNA RAPIDLY; (TCASII DISPLAY TA) AND SOMETHING POSITIVE HAD TO BE DONE IN A HURRY. I TURNED THE ACFT 90 DEGS TO THE R AND HAD THE FO TELL THE CTLR THAT OUR NEW HDG WAS 270 DEGS. WE THEN RECEIVED VECTORS BACK TO THE LOC COURSE AND COMPLETED OUR LNDG. FACTORS THAT CONTRIBUTED TO THE SIT: CTLRS QUICK TO GET THE CREWS TO CALL THE FIELD IN SIGHT FOR A VISUAL APCH. WEEKEND FLYERS IN SMALL PLANES AROUND CIVILIAN ARPTS. LARGE SPD DIFFERENCES BTWN JETS AND PROPS. APCH CTLRS WORKING MORE THAN 1 RADIO FREQ. AS A FINAL NOTE; OUR TCASII SYS WAS INVALUABLE IN THIS INSTANCE AND KEPT THIS FROM TURNING INTO A BAD SIT.