Narrative:

West operation, there was WX on the downwind. Air carrier X on downwind, did not want a 095 degree heading due to WX. He was tracking nnebound and I was concerned about him affecting traffic on the finals. I initially descended him to 4500 ft, then changed it to 5000 ft, due to his proximity to final. Air carrier Y, base leg traffic came over and I descended him to 3500 ft and reduced his speed to 150 KTS. X finally took my 095 degree heading and was not a factor for final traffic. My plan was to put Y, base leg traffic, on final first, followed by X. I asked Y to let me know when he had slowed. At the appropriate time, I turned Y to 285 degree and cleared him for the approach. He responded with his having reached 150 KTS. I went back to look at X, Y had continued on the 360 degree heading (base leg). Upon realizing that Y had not turned and joined, I turned him left to 240 degree. At this point, X became next, in front of Y, so I turned Y to 220 degree to make room. I then turned X to 300 degree heading to join in front of Y and cleared him for approach. After Y asked me if he should join the localizer, I said no, maintain heading 220 degree. I came right back and told turn heading 240 degree and join the localizer. Shortly thereafter, I turned X to 300 degree and cleared him for the approach. Shortly thereafter, I observed Y on a converging course with X and issued an immediate right to 360 degree. I then issued a left turn of 250 degree to X.

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Original NASA ASRS Text

Title: ACR X HAD LTSS FROM ACR Y WHILE ON RADAR VECTORS FOR APCH. SYS ERROR.

Narrative: WEST OPERATION, THERE WAS WX ON THE DOWNWIND. ACR X ON DOWNWIND, DID NOT WANT A 095 DEG HDG DUE TO WX. HE WAS TRACKING NNEBOUND AND I WAS CONCERNED ABOUT HIM AFFECTING TFC ON THE FINALS. I INITIALLY DSNDED HIM TO 4500 FT, THEN CHANGED IT TO 5000 FT, DUE TO HIS PROX TO FINAL. ACR Y, BASE LEG TFC CAME OVER AND I DSNDED HIM TO 3500 FT AND REDUCED HIS SPD TO 150 KTS. X FINALLY TOOK MY 095 DEG HDG AND WAS NOT A FACTOR FOR FINAL TFC. MY PLAN WAS TO PUT Y, BASE LEG TFC, ON FINAL FIRST, FOLLOWED BY X. I ASKED Y TO LET ME KNOW WHEN HE HAD SLOWED. AT THE APPROPRIATE TIME, I TURNED Y TO 285 DEG AND CLRED HIM FOR THE APCH. HE RESPONDED WITH HIS HAVING REACHED 150 KTS. I WENT BACK TO LOOK AT X, Y HAD CONTINUED ON THE 360 DEG HDG (BASE LEG). UPON REALIZING THAT Y HAD NOT TURNED AND JOINED, I TURNED HIM L TO 240 DEG. AT THIS POINT, X BECAME NEXT, IN FRONT OF Y, SO I TURNED Y TO 220 DEG TO MAKE ROOM. I THEN TURNED X TO 300 DEG HDG TO JOIN IN FRONT OF Y AND CLRED HIM FOR APCH. AFTER Y ASKED ME IF HE SHOULD JOIN THE LOC, I SAID NO, MAINTAIN HDG 220 DEG. I CAME RIGHT BACK AND TOLD TURN HDG 240 DEG AND JOIN THE LOC. SHORTLY THEREAFTER, I TURNED X TO 300 DEG AND CLRED HIM FOR THE APCH. SHORTLY THEREAFTER, I OBSERVED Y ON A CONVERGING COURSE WITH X AND ISSUED AN IMMEDIATE R TO 360 DEG. I THEN ISSUED A L TURN OF 250 DEG TO X.

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.