Narrative:

Air carrier X, medium large transport, departed cak climbed to FL220 going to ord; leveled at FL220 approximately 20 east of mfd VOR. The sector became complex very fast with overflts and departures off cle as well as an inbound to bjj handed off by another sector at FL210 (usually these aircraft are below the center's airspace). Air carrier Y, medium large transport departed cmh and was handed off to my sector southwest of the mfd VOR. When the handoff was accepted, the data block showed the aircraft out of 17000 so I (as common practice) inserted FL230 as a temporary altitude and flashed the handoff to my high altitude sector who then inserted FL290 in air carrier X data block, thus releasing that altitude in their airspace. Air carrier Y checked on out of 15000 ft climbing to FL230, but I initially stopped him at FL210 (with out changing the data block) I was now talking to 10 airplanes and the high altitude sector was trying to handoff a pit inbound usually handed off to the sector to the east of mine. This extra data block kept covering data blocks of my own. I scanned back to the air carrier Y data block and saw FL290 and climbed him. Prior to this I had assigned air carrier X a 200' heading. The high altitude sector called on the override to tell me to stop air carrier Y at FL240. When I looked back at the data block while telling air carrier Y to stop his climb at FL240, I realized I'd put him in confliction with air carrier X and immediately turned both aircraft. Separation had been lost, but the aircraft kept apart. The air carrier Y pilot tied up my frequency (while I awaited relief) by saying 3 times 'we had him, how close was he?' I could not answer the pilot because I had other sits to take care of. After reviewing the tape, I also heard air carrier Y's final comment 'that was close, better learn to space them.' I realize the man's concern, but tying up the frequency at that time was critical.

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Original NASA ASRS Text

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

Narrative: ACR X, MLG, DEPARTED CAK CLBED TO FL220 GOING TO ORD; LEVELED AT FL220 APPROX 20 E OF MFD VOR. THE SECTOR BECAME COMPLEX VERY FAST WITH OVERFLTS AND DEPS OFF CLE AS WELL AS AN INBND TO BJJ HANDED OFF BY ANOTHER SECTOR AT FL210 (USUALLY THESE ACFT ARE BELOW THE CTR'S AIRSPACE). ACR Y, MLG DEPARTED CMH AND WAS HANDED OFF TO MY SECTOR SW OF THE MFD VOR. WHEN THE HDOF WAS ACCEPTED, THE DATA BLOCK SHOWED THE ACFT OUT OF 17000 SO I (AS COMMON PRACTICE) INSERTED FL230 AS A TEMPORARY ALT AND FLASHED THE HDOF TO MY HIGH ALT SECTOR WHO THEN INSERTED FL290 IN ACR X DATA BLOCK, THUS RELEASING THAT ALT IN THEIR AIRSPACE. ACR Y CHKED ON OUT OF 15000 FT CLBING TO FL230, BUT I INITIALLY STOPPED HIM AT FL210 (WITH OUT CHANGING THE DATA BLOCK) I WAS NOW TALKING TO 10 AIRPLANES AND THE HIGH ALT SECTOR WAS TRYING TO HDOF A PIT INBND USUALLY HANDED OFF TO THE SECTOR TO THE E OF MINE. THIS EXTRA DATA BLOCK KEPT COVERING DATA BLOCKS OF MY OWN. I SCANNED BACK TO THE ACR Y DATA BLOCK AND SAW FL290 AND CLBED HIM. PRIOR TO THIS I HAD ASSIGNED ACR X A 200' HDG. THE HIGH ALT SECTOR CALLED ON THE OVERRIDE TO TELL ME TO STOP ACR Y AT FL240. WHEN I LOOKED BACK AT THE DATA BLOCK WHILE TELLING ACR Y TO STOP HIS CLB AT FL240, I REALIZED I'D PUT HIM IN CONFLICTION WITH ACR X AND IMMEDIATELY TURNED BOTH ACFT. SEPARATION HAD BEEN LOST, BUT THE ACFT KEPT APART. THE ACR Y PLT TIED UP MY FREQ (WHILE I AWAITED RELIEF) BY SAYING 3 TIMES 'WE HAD HIM, HOW CLOSE WAS HE?' I COULD NOT ANSWER THE PLT BECAUSE I HAD OTHER SITS TO TAKE CARE OF. AFTER REVIEWING THE TAPE, I ALSO HEARD ACR Y'S FINAL COMMENT 'THAT WAS CLOSE, BETTER LEARN TO SPACE THEM.' I REALIZE THE MAN'S CONCERN, BUT TYING UP THE FREQ AT THAT TIME WAS CRITICAL.

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.