Narrative:

I was working gsp east and south radar positions combined and with a trainee. Air carrier X was wbound landing from clt at 10000 ft. Small aircraft Y (C210) was sebound on V53 from spa to burba intersection at 9000 ft. The watch supervisor, working flight data, answered the clt voice line and approved X descending to 9000 ft. He advised the trainee of this, but did not tell me. The trainee did not notice the developing conflict and, as far as I knew, X was going to be at 10000 ft per our procedures. By the time I noticed X had descended to 9000 ft, he was already in conflict with Y. I took over the position from the trainee and told X to 'turn left heading 180 degrees immediately for traffic.' the turn alone resolved the conflict, but resulted in less than the required 3 NM separation. I then descended X and turned him back to the west when he was through 8000 ft. The main cause of this problem was the supervisor's failure to inform me, the person responsible for the position, of coordination he had performed affecting the separation of my traffic. Also, if he had approved an altitude appropriate for direction, ie, 8000 ft wbound this may have never happened. There was also no reason for him to get on the coordination line to start with, we had things under control, and were not that busy. The flight data position has no control authority/authorized/responsibility anyway. X was equipped with TCASII, but as far as I know, no RA was given by TCASII.

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Original NASA ASRS Text

Title: ACR X DSCNT TO OCCUPIED ALT HAD LTSS FROM SMT Y. SYS ERROR.

Narrative: I WAS WORKING GSP E AND S RADAR POSITIONS COMBINED AND WITH A TRAINEE. ACR X WAS WBOUND LNDG FROM CLT AT 10000 FT. SMA Y (C210) WAS SEBOUND ON V53 FROM SPA TO BURBA INTXN AT 9000 FT. THE WATCH SUPVR, WORKING FLT DATA, ANSWERED THE CLT VOICE LINE AND APPROVED X DSNDING TO 9000 FT. HE ADVISED THE TRAINEE OF THIS, BUT DID NOT TELL ME. THE TRAINEE DID NOT NOTICE THE DEVELOPING CONFLICT AND, AS FAR AS I KNEW, X WAS GOING TO BE AT 10000 FT PER OUR PROCS. BY THE TIME I NOTICED X HAD DSNDED TO 9000 FT, HE WAS ALREADY IN CONFLICT WITH Y. I TOOK OVER THE POS FROM THE TRAINEE AND TOLD X TO 'TURN L HDG 180 DEGS IMMEDIATELY FOR TFC.' THE TURN ALONE RESOLVED THE CONFLICT, BUT RESULTED IN LESS THAN THE REQUIRED 3 NM SEPARATION. I THEN DSNDED X AND TURNED HIM BACK TO THE W WHEN HE WAS THROUGH 8000 FT. THE MAIN CAUSE OF THIS PROB WAS THE SUPVR'S FAILURE TO INFORM ME, THE PERSON RESPONSIBLE FOR THE POS, OF COORD HE HAD PERFORMED AFFECTING THE SEPARATION OF MY TFC. ALSO, IF HE HAD APPROVED AN ALT APPROPRIATE FOR DIRECTION, IE, 8000 FT WBOUND THIS MAY HAVE NEVER HAPPENED. THERE WAS ALSO NO REASON FOR HIM TO GET ON THE COORD LINE TO START WITH, WE HAD THINGS UNDER CTL, AND WERE NOT THAT BUSY. THE FLT DATA POS HAS NO CTL AUTH/RESPONSIBILITY ANYWAY. X WAS EQUIPPED WITH TCASII, BUT AS FAR AS I KNOW, NO RA WAS GIVEN BY TCASII.

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.