Narrative:

Aircraft X was level at FL220 direct aco and aircraft Y was on a heading and descent for sequencing into cle approach airspace. Separation was lost between the 2 aircraft. Traffic was very complex and busy at the time of the incident.

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Original NASA ASRS Text

Title: ZOB CTLR IS DISTR WITH SECTOR TFC VOLUME AND DOES NOT OBSERVE CONFLICT UNTIL TOO LATE TO ENSURE POSITIVE CTLR SEPARATION.

Narrative: ACFT X WAS LEVEL AT FL220 DIRECT ACO AND ACFT Y WAS ON A HDG AND DSCNT FOR SEQUENCING INTO CLE APCH AIRSPACE. SEPARATION WAS LOST BTWN THE 2 ACFT. TFC WAS VERY COMPLEX AND BUSY AT THE TIME OF THE INCIDENT.

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.