Narrative:

Air carrier X was being vectored to a left downwind to runway 36C from the northeast. Air carrier Y was on the arrival to runway 36C from the northwest. Air carrier X was well ahead of air carrier Y in the sequence; but slowed on their own and did not advise. When I saw this; I gave air carrier X a clearance from 110 degrees to 90 degrees. Air carrier Z was 8 mi behind air carrier X from the northeast being moved from runway 36R from runway 36L. I was making air carrier Z next behind air carrier X in my plan; however; the other arrival controller did not put this aircraft on my frequency. I turned air carrier Y 15 degrees left to make room for air carrier Z. When air carrier Z did not come to my frequency; I turned air carrier Y back to cvg and descended the aircraft from 11000 ft to 7000 ft. I was reaching out for air carrier Z (who was being vectored to runway 36L for parking convenience). Air carrier west was checking in on the frequency and answered and took controller instructions for air carrier Z. I turned air carrier X left to 180 degrees and descended him to 7000 ft. I turned air carrier Y to 090 degrees and immediately called air carrier Z to turn right heading 330 degrees. Air carrier Z paused and said 'was that for air carrier Z?' (almost creating another situation.) at the time the instructions to air carrier X were issued; air carrier X and air carrier Y were 6.5 mi apart. Air carrier X was turning slowly. Air carrier X and air carrier Y were 2.75 mi lateral and was investigated as a possible operational error. It was determined that diverging course separation existed. In the middle of the event; I had to go back and fix air carrier Z who slowed to 180 KTS; 40 mi from the airport with another aircraft behind him 10 mi on the arrival doing 310 KTS.

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Original NASA ASRS Text

Title: CVG CTLR EXPLAINS NEAR OPERROR AT 10000 FT WHEN ADJACENT CTLR'S OPS PLAN DIFFERED AND ALL ACFT WERE NOT ON THE RPTR'S FREQ.

Narrative: ACR X WAS BEING VECTORED TO A L DOWNWIND TO RWY 36C FROM THE NE. ACR Y WAS ON THE ARR TO RWY 36C FROM THE NW. ACR X WAS WELL AHEAD OF ACR Y IN THE SEQUENCE; BUT SLOWED ON THEIR OWN AND DID NOT ADVISE. WHEN I SAW THIS; I GAVE ACR X A CLRNC FROM 110 DEGS TO 90 DEGS. ACR Z WAS 8 MI BEHIND ACR X FROM THE NE BEING MOVED FROM RWY 36R FROM RWY 36L. I WAS MAKING ACR Z NEXT BEHIND ACR X IN MY PLAN; HOWEVER; THE OTHER ARR CTLR DID NOT PUT THIS ACFT ON MY FREQ. I TURNED ACR Y 15 DEGS L TO MAKE ROOM FOR ACR Z. WHEN ACR Z DID NOT COME TO MY FREQ; I TURNED ACR Y BACK TO CVG AND DSNDED THE ACFT FROM 11000 FT TO 7000 FT. I WAS REACHING OUT FOR ACR Z (WHO WAS BEING VECTORED TO RWY 36L FOR PARKING CONVENIENCE). ACR W WAS CHKING IN ON THE FREQ AND ANSWERED AND TOOK CTLR INSTRUCTIONS FOR ACR Z. I TURNED ACR X L TO 180 DEGS AND DSNDED HIM TO 7000 FT. I TURNED ACR Y TO 090 DEGS AND IMMEDIATELY CALLED ACR Z TO TURN R HDG 330 DEGS. ACR Z PAUSED AND SAID 'WAS THAT FOR ACR Z?' (ALMOST CREATING ANOTHER SIT.) AT THE TIME THE INSTRUCTIONS TO ACR X WERE ISSUED; ACR X AND ACR Y WERE 6.5 MI APART. ACR X WAS TURNING SLOWLY. ACR X AND ACR Y WERE 2.75 MI LATERAL AND WAS INVESTIGATED AS A POSSIBLE OPERROR. IT WAS DETERMINED THAT DIVERGING COURSE SEPARATION EXISTED. IN THE MIDDLE OF THE EVENT; I HAD TO GO BACK AND FIX ACR Z WHO SLOWED TO 180 KTS; 40 MI FROM THE ARPT WITH ANOTHER ACFT BEHIND HIM 10 MI ON THE ARR DOING 310 KTS.

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.