Narrative:

ZTL sectors 17 and 18 were combined and r-side training was in progress. I was taking a briefing to relieve the r-side/trainee so that they could open sector 18. It was very busy. The r-side was having trouble briefing me due to the volume. Aircraft Y was at 9000 ft; transitioning sector 18 into sector 17. I took the handoff at sector 17; thinking sector 18 had handed him off. It turns out sector 38 had handed aircraft X off to sector 18; which not being open; was forced to sector 17. Seconds later; sector 18 was opened and split off. I took the handoff on aircraft X from sector 16; descending to 11000 ft; landing 30GA; about 40 mi away. I descended aircraft X to 10000 ft; due to head-on traffic at 9000 ft; aircraft Y. I switched aircraft X to sector 18. The trainee descended aircraft X to 6000 ft; not seeing the limited data block on aircraft Y; who was still in sector 18. This instigated the error. If we had the staffing and time to split sectors when needed; this never would have happened. It was so hectic and busy we made assumptions we shouldn't have. If the sector 18 had been opened moments earlier; the handoff from sector 38 would not have gone to sector 18 instead of sector 17. At the time; I had no way of knowing who handed off aircraft Y to me. I wrongly assumed it was sector 18; the adjacent sector.

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Original NASA ASRS Text

Title: ZTL CTLR EXPERIENCED OPERROR DURING SECTOR DE-COMBINING EFFORTS DURING BUSY TFC WHILE TRAINING WAS BEING CONDUCTED.

Narrative: ZTL SECTORS 17 AND 18 WERE COMBINED AND R-SIDE TRAINING WAS IN PROGRESS. I WAS TAKING A BRIEFING TO RELIEVE THE R-SIDE/TRAINEE SO THAT THEY COULD OPEN SECTOR 18. IT WAS VERY BUSY. THE R-SIDE WAS HAVING TROUBLE BRIEFING ME DUE TO THE VOLUME. ACFT Y WAS AT 9000 FT; TRANSITIONING SECTOR 18 INTO SECTOR 17. I TOOK THE HDOF AT SECTOR 17; THINKING SECTOR 18 HAD HANDED HIM OFF. IT TURNS OUT SECTOR 38 HAD HANDED ACFT X OFF TO SECTOR 18; WHICH NOT BEING OPEN; WAS FORCED TO SECTOR 17. SECONDS LATER; SECTOR 18 WAS OPENED AND SPLIT OFF. I TOOK THE HDOF ON ACFT X FROM SECTOR 16; DSNDING TO 11000 FT; LNDG 30GA; ABOUT 40 MI AWAY. I DSNDED ACFT X TO 10000 FT; DUE TO HEAD-ON TFC AT 9000 FT; ACFT Y. I SWITCHED ACFT X TO SECTOR 18. THE TRAINEE DSNDED ACFT X TO 6000 FT; NOT SEEING THE LIMITED DATA BLOCK ON ACFT Y; WHO WAS STILL IN SECTOR 18. THIS INSTIGATED THE ERROR. IF WE HAD THE STAFFING AND TIME TO SPLIT SECTORS WHEN NEEDED; THIS NEVER WOULD HAVE HAPPENED. IT WAS SO HECTIC AND BUSY WE MADE ASSUMPTIONS WE SHOULDN'T HAVE. IF THE SECTOR 18 HAD BEEN OPENED MOMENTS EARLIER; THE HDOF FROM SECTOR 38 WOULD NOT HAVE GONE TO SECTOR 18 INSTEAD OF SECTOR 17. AT THE TIME; I HAD NO WAY OF KNOWING WHO HANDED OFF ACFT Y TO ME. I WRONGLY ASSUMED IT WAS SECTOR 18; THE ADJACENT SECTOR.

Data retrieved from NASA's ASRS site as of January 2009 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.