Narrative:

Air carrier X was an inbound to clt on the sudsy 1 arrival 220 down to 130. Aircraft Y was a BE40 departure off of svh nebound to bdl 115 up to 230. Aircraft Y was originally on a heading to the northeast where if I had left him alone would have separated him from the air carrier X. I vectored him to the right attempting to cross him out with air carrier X who was descending on the arrival. This would have enabled aircraft Y to be on course sooner. I had originally thought the aircraft Y would climb very well. There was at least 50-60 KTS on his tail. I realized this and shortly after I gave him the clearance I was skeptical that this would work. However instead of ending it at that time and stepping both aircraft off at altitude; I decided to give it a little more time. I even asked both aircraft to keep a good rate of descent and a good rate of climb. When I finally decided it was not going to work I attempted to step both aircraft off. The first time I tried to step aircraft Y off it was answered by another aircraft on frequency. On the second attempt aircraft Y acknowledged the change of altitude. I attempted to step aircraft X off at 170 3 times. On the 3RD time he acknowledged. I asked aircraft Y to verify his altitude at 160. He responded in the negative and that he had the aircraft X in sight. The air carrier X reported that he was at 170 and had turned for the aircraft Y. I cannot explain to myself let alone someone else how I could let a simple situation get out of my control.

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Original NASA ASRS Text

Title: ZTL CTLR EXPERIENCED OPERROR AT 17000 WHEN FAILING TO TAKE TIMELY ACTION BETWEEN A CLIMBING AND DESCENDING ACFT.

Narrative: ACR X WAS AN INBOUND TO CLT ON THE SUDSY 1 ARR 220 DOWN TO 130. ACFT Y WAS A BE40 DEP OFF OF SVH NEBOUND TO BDL 115 UP TO 230. ACFT Y WAS ORIGINALLY ON A HDG TO THE NE WHERE IF I HAD LEFT HIM ALONE WOULD HAVE SEPARATED HIM FROM THE ACR X. I VECTORED HIM TO THE R ATTEMPTING TO CROSS HIM OUT WITH ACR X WHO WAS DSNDING ON THE ARR. THIS WOULD HAVE ENABLED ACFT Y TO BE ON COURSE SOONER. I HAD ORIGINALLY THOUGHT THE ACFT Y WOULD CLB VERY WELL. THERE WAS AT LEAST 50-60 KTS ON HIS TAIL. I REALIZED THIS AND SHORTLY AFTER I GAVE HIM THE CLRNC I WAS SKEPTICAL THAT THIS WOULD WORK. HOWEVER INSTEAD OF ENDING IT AT THAT TIME AND STEPPING BOTH ACFT OFF AT ALT; I DECIDED TO GIVE IT A LITTLE MORE TIME. I EVEN ASKED BOTH ACFT TO KEEP A GOOD RATE OF DSCNT AND A GOOD RATE OF CLB. WHEN I FINALLY DECIDED IT WAS NOT GOING TO WORK I ATTEMPTED TO STEP BOTH ACFT OFF. THE FIRST TIME I TRIED TO STEP ACFT Y OFF IT WAS ANSWERED BY ANOTHER ACFT ON FREQ. ON THE SECOND ATTEMPT ACFT Y ACKNOWLEDGED THE CHANGE OF ALT. I ATTEMPTED TO STEP ACFT X OFF AT 170 3 TIMES. ON THE 3RD TIME HE ACKNOWLEDGED. I ASKED ACFT Y TO VERIFY HIS ALT AT 160. HE RESPONDED IN THE NEGATIVE AND THAT HE HAD THE ACFT X IN SIGHT. THE ACR X RPTED THAT HE WAS AT 170 AND HAD TURNED FOR THE ACFT Y. I CANNOT EXPLAIN TO MYSELF LET ALONE SOMEONE ELSE HOW I COULD LET A SIMPLE SITUATION GET OUT OF MY CTL.

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.