Narrative:

We were given an initial heading after roberts of 220 degree to intercept the localizer. The controller changed our heading to 240 degree. We assumed controller still wanted us to intercept, controller did not. But we didn't know that until we had already intercepted and controller called us. We then turned right to 240 degree and controller said we missed traffic by 2 mi but we could now track the localizer and controller gave us a 180 heading to intercept. There was a little doubt in my mind as to whether or not to intercept the localizer and I should have cleared that up with the controller before intercepting. Supplemental information from acn 180468: subsequently, we received a change of heading clearance to 240 degree. We understood that the new heading was also to intercept the localizer. Just prior to completing our turn to intercept the localizer the controller contacted us and asked us if we had turned to intercept. While I replied 'yes', the captain sensed we were in error and began an immediate turn back to our last assigned heading of 240 degree. The controller replied that we could now intercept and gave us a heading of 180 degree. Controller also added that we had missed traffic by 2 mi.

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Original NASA ASRS Text

Title: FLC WAS GIVEN HDG FOR VECTOR TO ILS, INTERCEPTED ILS WITHOUT CLRNC AND HAD LTSS WITH ANOTHER ACFT.

Narrative: WE WERE GIVEN AN INITIAL HDG AFTER ROBERTS OF 220 DEG TO INTERCEPT THE LOC. THE CTLR CHANGED OUR HDG TO 240 DEG. WE ASSUMED CTLR STILL WANTED US TO INTERCEPT, CTLR DID NOT. BUT WE DIDN'T KNOW THAT UNTIL WE HAD ALREADY INTERCEPTED AND CTLR CALLED US. WE THEN TURNED R TO 240 DEG AND CTLR SAID WE MISSED TFC BY 2 MI BUT WE COULD NOW TRACK THE LOC AND CTLR GAVE US A 180 HDG TO INTERCEPT. THERE WAS A LITTLE DOUBT IN MY MIND AS TO WHETHER OR NOT TO INTERCEPT THE LOC AND I SHOULD HAVE CLRED THAT UP WITH THE CTLR BEFORE INTERCEPTING. SUPPLEMENTAL INFO FROM ACN 180468: SUBSEQUENTLY, WE RECEIVED A CHANGE OF HDG CLRNC TO 240 DEG. WE UNDERSTOOD THAT THE NEW HDG WAS ALSO TO INTERCEPT THE LOC. JUST PRIOR TO COMPLETING OUR TURN TO INTERCEPT THE LOC THE CTLR CONTACTED US AND ASKED US IF WE HAD TURNED TO INTERCEPT. WHILE I REPLIED 'YES', THE CAPT SENSED WE WERE IN ERROR AND BEGAN AN IMMEDIATE TURN BACK TO OUR LAST ASSIGNED HDG OF 240 DEG. THE CTLR REPLIED THAT WE COULD NOW INTERCEPT AND GAVE US A HDG OF 180 DEG. CTLR ALSO ADDED THAT WE HAD MISSED TFC BY 2 MI.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.