Narrative:

I was vectoring the citation and regional jet to mke. The regional jet was approximately 6 mi behind the citation. Both were descending to 7000 ft. I observed an aircraft (the baron) on another controller's tag at 8000 ft and questioned who he was and where he was going. Realizing the conflict between the citation and the baron; I requested the other controller turn the baron and I turned the citation. After the conflict was resolved; the other controller turned the baron back on course; causing a conflict with the regional jet; whom I immediately turned to avoid the baron. In the position relief briefing; mention was made of 8000 ft traffic; but no specific call sign. I should have questioned this; but I didn't; leaving myself unaware of the baron traffic. Supplemental information from acn 672100: the baron was handed off to me from the east sector on course at 8000 ft; with communications xferred to me shortly after. The east sector then changed controllers. Shortly after this personnel change; the 'new' east sector controller began to question me who the baron was. I informed this controller that the previous controller had handed this aircraft off to me at 8000 ft and that the aircraft was on course to jyr. The new east sector controller asked if I was going to turn out of his way. I then looked to see the citation; opposite direction to the baron; descending out of 9000 ft and approximately 5 NM away. I turned the baron to a 340 degree heading to avoid this traffic. It was after that that the east sector controller turned the aircraft to also avoid. After both aircraft were separated by 5 mi; I instructed aircraft Y to resume own navigation. Shortly after this; the east sector controller was yelling at me and inquiring whether the baron was on course. I said yes; because that is how I received the aircraft. I then observed a second mke arrival (a regional jet) descending opposite direction to the baron out of 9000 ft. The east sector controller turned the regional jet to resolve the second conflict.

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Original NASA ASRS Text

Title: MKC CTLR EXPERIENCED OPERROR AT 8000 FT WHILE VECTORING 2 ACFT TOWARD THE MKE FINAL.

Narrative: I WAS VECTORING THE CITATION AND REGIONAL JET TO MKE. THE REGIONAL JET WAS APPROX 6 MI BEHIND THE CITATION. BOTH WERE DSNDING TO 7000 FT. I OBSERVED AN ACFT (THE BARON) ON ANOTHER CTLR'S TAG AT 8000 FT AND QUESTIONED WHO HE WAS AND WHERE HE WAS GOING. REALIZING THE CONFLICT BTWN THE CITATION AND THE BARON; I REQUESTED THE OTHER CTLR TURN THE BARON AND I TURNED THE CITATION. AFTER THE CONFLICT WAS RESOLVED; THE OTHER CTLR TURNED THE BARON BACK ON COURSE; CAUSING A CONFLICT WITH THE REGIONAL JET; WHOM I IMMEDIATELY TURNED TO AVOID THE BARON. IN THE POS RELIEF BRIEFING; MENTION WAS MADE OF 8000 FT TFC; BUT NO SPECIFIC CALL SIGN. I SHOULD HAVE QUESTIONED THIS; BUT I DIDN'T; LEAVING MYSELF UNAWARE OF THE BARON TFC. SUPPLEMENTAL INFO FROM ACN 672100: THE BARON WAS HANDED OFF TO ME FROM THE E SECTOR ON COURSE AT 8000 FT; WITH COMS XFERRED TO ME SHORTLY AFTER. THE E SECTOR THEN CHANGED CTLRS. SHORTLY AFTER THIS PERSONNEL CHANGE; THE 'NEW' E SECTOR CTLR BEGAN TO QUESTION ME WHO THE BARON WAS. I INFORMED THIS CTLR THAT THE PREVIOUS CTLR HAD HANDED THIS ACFT OFF TO ME AT 8000 FT AND THAT THE ACFT WAS ON COURSE TO JYR. THE NEW E SECTOR CTLR ASKED IF I WAS GOING TO TURN OUT OF HIS WAY. I THEN LOOKED TO SEE THE CITATION; OPPOSITE DIRECTION TO THE BARON; DSNDING OUT OF 9000 FT AND APPROX 5 NM AWAY. I TURNED THE BARON TO A 340 DEG HDG TO AVOID THIS TFC. IT WAS AFTER THAT THAT THE E SECTOR CTLR TURNED THE ACFT TO ALSO AVOID. AFTER BOTH ACFT WERE SEPARATED BY 5 MI; I INSTRUCTED ACFT Y TO RESUME OWN NAV. SHORTLY AFTER THIS; THE E SECTOR CTLR WAS YELLING AT ME AND INQUIRING WHETHER THE BARON WAS ON COURSE. I SAID YES; BECAUSE THAT IS HOW I RECEIVED THE ACFT. I THEN OBSERVED A SECOND MKE ARR (A REGIONAL JET) DSNDING OPPOSITE DIRECTION TO THE BARON OUT OF 9000 FT. THE E SECTOR CTLR TURNED THE REGIONAL JET TO RESOLVE THE SECOND CONFLICT.

Data retrieved from NASA's ASRS site as of January 2009 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.