Narrative:

18 aircraft on frequency. I was asked to provide in trail to dfw airport. I issued vectors to 4 aircraft including the 2 aircraft involved. Because of the many other aircraft in the area, I had to move 2 other aircraft in the area to avoid conflictions with the aircraft on vectors. During my scan of the radar I noticed the 2 aircraft in confliction, but was only able to use altitude separation initially due to other traffic above and below the aircraft involved. I initiated vectors to both aircraft and as soon as possible I issued a descent to aircraft X, MD80, and a climb to aircraft Y, CRJ2, I was unable to maintain separation.

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Original NASA ASRS Text

Title: ZAU RADAR CTLR UNABLE TO MAINTAIN SEPARATION BTWN 2 ACFT BECAUSE OF SECTOR SATURATION.

Narrative: 18 ACFT ON FREQ. I WAS ASKED TO PROVIDE IN TRAIL TO DFW ARPT. I ISSUED VECTORS TO 4 ACFT INCLUDING THE 2 ACFT INVOLVED. BECAUSE OF THE MANY OTHER ACFT IN THE AREA, I HAD TO MOVE 2 OTHER ACFT IN THE AREA TO AVOID CONFLICTIONS WITH THE ACFT ON VECTORS. DURING MY SCAN OF THE RADAR I NOTICED THE 2 ACFT IN CONFLICTION, BUT WAS ONLY ABLE TO USE ALT SEPARATION INITIALLY DUE TO OTHER TFC ABOVE AND BELOW THE ACFT INVOLVED. I INITIATED VECTORS TO BOTH ACFT AND AS SOON AS POSSIBLE I ISSUED A DSCNT TO ACFT X, MD80, AND A CLB TO ACFT Y, CRJ2, I WAS UNABLE TO MAINTAIN SEPARATION.

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.