Narrative:

The B727 (air carrier X) was climbing slowly head on with the C550 (aircraft Y) at a range of 30-35 mi. My radar associate coordinated with the receiving sector that each aircraft would be turned right. They turned the C550 15 degrees right and I turned the B727 30 degrees right. My d-side also coordinated that we would provide separation between the aircraft, but did not tell me that. I switched the B727 to the next frequency under the assumption that they were separating the traffic. The B727 did not begin the turn for nearly 1 min, and separation was lost. During this time, I had at least 24 data blocks on my scope, moderate chop/turbulence and complex traffic. The cvg approach control was handing our facility departures at a high rate without any flow control restrs. I feel the important factors leading to this incident were: the B727 did not turn in a timely manner, lack of communication in my sector team, and lack of flow control restrs placed on cvg during a busy period in turbulent conditions.

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Original NASA ASRS Text

Title: AN ARTCC CTLR ASSUMED THAT THE NEXT CTL SECTOR WOULD ENSURE SEPARATION BTWN OPPOSITE DIRECTION CLBING B727 AND A LEVEL FLT C550. THE RPTR STATES THE D CTLR FAILED TO ADVISE HIM THAT HE WAS TO ENSURE SEPARATION PRIOR TO COM XFER.

Narrative: THE B727 (ACR X) WAS CLBING SLOWLY HEAD ON WITH THE C550 (ACFT Y) AT A RANGE OF 30-35 MI. MY RADAR ASSOCIATE COORDINATED WITH THE RECEIVING SECTOR THAT EACH ACFT WOULD BE TURNED R. THEY TURNED THE C550 15 DEGS R AND I TURNED THE B727 30 DEGS R. MY D-SIDE ALSO COORDINATED THAT WE WOULD PROVIDE SEPARATION BTWN THE ACFT, BUT DID NOT TELL ME THAT. I SWITCHED THE B727 TO THE NEXT FREQ UNDER THE ASSUMPTION THAT THEY WERE SEPARATING THE TFC. THE B727 DID NOT BEGIN THE TURN FOR NEARLY 1 MIN, AND SEPARATION WAS LOST. DURING THIS TIME, I HAD AT LEAST 24 DATA BLOCKS ON MY SCOPE, MODERATE CHOP/TURB AND COMPLEX TFC. THE CVG APCH CTL WAS HANDING OUR FACILITY DEPS AT A HIGH RATE WITHOUT ANY FLOW CTL RESTRS. I FEEL THE IMPORTANT FACTORS LEADING TO THIS INCIDENT WERE: THE B727 DID NOT TURN IN A TIMELY MANNER, LACK OF COM IN MY SECTOR TEAM, AND LACK OF FLOW CTL RESTRS PLACED ON CVG DURING A BUSY PERIOD IN TURBULENT CONDITIONS.

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.