MIL ACFT HAS NMAC ON VECTORS FOR ILS APCH.

Narrative

ON VECTORS FOR FINAL ILS 17R. LEVEL AT 9000 FT; 260 DEG HDG; 180 KTS; BASE LEG. APCH CTL CALLED OUT TFC AT OUR 12 O'CLOCK POS; DSNDING FOR LNDG AT COS. THAT TFC WAS NEVER SEEN; NOR EVER BECAME A FACTOR. AS WE WERE BEING VECTORED ACROSS THE LOC; I ASKED APCH CTL IF THEY WANTED US TO TURN TO INTERCEPT. THEY GAVE US A TURN TO 150 DEG HDG TO INTERCEPT THE ILS 17R LOC (FROM THE W); CLRED FOR THE APCH. IMMEDIATELY AFTER RECEIVING THE NEW VECTOR; THE OTHER ACFT PASSED APPROX 150-200 FT OVER THE TOP OF US ON A SOUTHERLY HDG. FROM THE TIME WE SAW THE OTHER ACFT UNTIL HE PASSED OVER US WAS A MATTER OF A FEW SECONDS; WITH NO TIME TO REACT; OR TAKE EVASIVE ACTION. IT APPEARED THE OTHER ACFT WAS IN A CLB. THE WX WAS VMC; WE WERE ON AN IFR CLRNC IN VMC; OUTSIDE THE COS ARSA. THERE WAS NO EVASIVE ACTION TAKEN ON OUR PART; AND APPARENTLY NOT BY THE OTHER ACFT AS WELL. WE WERE HDG TO THE W; INTO A LOW SUN OVER THE MOUNTAINS WITH THE ENTIRE CREW LOOKING OUTSIDE FOR TFC; BUT MOSTLY FROM OUR 12 - 9 O'CLOCK POS DUE TO THE OTHER TFC THAT WAS CALLED OUT PREVIOUSLY. APCH CTL NEVER ADVISED US OF THE TFC; AND ADVISED US THEY DIDN'T PICK THEM UP UNTIL THEY WERE APPROX 1 NM AWAY. NO DAMAGE OCCURRED. DO NOT BELIEVE THERE WAS A DEP OR DEV FROM ANY RULES OR REGS ON EITHER PLT'S PART. LESSONS LEARNED: 1) CAN NEVER BE TOO DILIGENT IN CLRING FOR OTHER TFC. 2) WE DEPARTED COS FOR A RADAR PATTERN; AND WERE INITIALLY GIVEN THE FREQ FOR THE SOUTHERN SECTOR (124.0). WE WERE NEVER CHANGED OVER TO THE NORTHERN SECTOR FREQ (118.5) DURING THE APCH. HAD THIS BEEN THE CASE; THE OTHER TFC MAY HAVE HEARD US ON THE APCH AND KNOWN WE WERE IN THAT AREA FOR THE APCH; AND MIGHT HAVE SEEN US SOONER; AND WE MIGHT HAVE HEARD HIM; AND ALSO SEEN HIM SOONER.