Narrative:

Air carrier X was at FL290 holding west on the 290 right of the dqn VORTAC. Air carrier Y was an overflt from stl to pit at FL290. Air carrier Y was not idented as traffic for air carrier X as he entered the sector well south and was eastbound. Several other aircraft were also in confliction and required my immediate attention. When these were resolved a review of air carrier Y and air carrier X situation indicated action needed to be taken but vertical sep could not be gained before lateral sep was lost. Callback conversation with reporter revealed the following information. The reporter stated he thought air carrier Y would pass south of the holding pattern. The computer plot after the incident air carrier Y was drifting toward the holding pattern which the reporter failed to recognize. Position relief took place and the relieving controller had been working the position 1 min prior to the loss of sep between air carrier X and Y. Air carrier X was descended and air carrier Y was turned. Conflict alert activated at the same time edp went off.

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Original NASA ASRS Text

Title: ACR X HAD LESS THAN STANDARD SEPARATION FROM ACR Y. SYSTEM ERROR.

Narrative: ACR X WAS AT FL290 HOLDING W ON THE 290 R OF THE DQN VORTAC. ACR Y WAS AN OVERFLT FROM STL TO PIT AT FL290. ACR Y WAS NOT IDENTED AS TFC FOR ACR X AS HE ENTERED THE SECTOR WELL S AND WAS EBND. SEVERAL OTHER ACFT WERE ALSO IN CONFLICTION AND REQUIRED MY IMMEDIATE ATTN. WHEN THESE WERE RESOLVED A REVIEW OF ACR Y AND ACR X SITUATION INDICATED ACTION NEEDED TO BE TAKEN BUT VERT SEP COULD NOT BE GAINED BEFORE LATERAL SEP WAS LOST. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO. THE RPTR STATED HE THOUGHT ACR Y WOULD PASS S OF THE HOLDING PATTERN. THE COMPUTER PLOT AFTER THE INCIDENT ACR Y WAS DRIFTING TOWARD THE HOLDING PATTERN WHICH THE RPTR FAILED TO RECOGNIZE. POS RELIEF TOOK PLACE AND THE RELIEVING CTLR HAD BEEN WORKING THE POS 1 MIN PRIOR TO THE LOSS OF SEP BTWN ACR X AND Y. ACR X WAS DSNDED AND ACR Y WAS TURNED. CONFLICT ALERT ACTIVATED AT THE SAME TIME EDP WENT OFF.

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.