Narrative:

At the time of the incident I had a B-767, X, to europe depart runway 1R and an ATR-42 depart runway 1L. I climbed the b- 767 to 10000 ft and the ATR-42 to 9000 ft. The B-767 was in a circled 360 degree heading and the ATR-42 Y was on a circled 340 degree heading. Prior to these aircraft, I had a C-210 depart VFR that I did not speak to for 6 mi. He was northeast of the airport at 1500 ft, technically not in my airspace. North arrival had an aircraft at the same altitude, merging, and we were trying to resolve that. I also had a ba-31 about 20 mi northwest cleared to 11000 ft climbing out of 4500 ft, which I pointed out to north arrival and he could not approve, so I had to vector that aircraft for the climb. I do not know how many other aircraft were on my frequency. I also had an aircraft with an incorrect mode C readout. At this point things were getting untenable. I had a 7000 ft overflt come into my airspace with no acceptance of a handoff. I stopped the ATR-42 and the B-767 at 6000 ft. I also, sometime during this time period, stopped the departures twice. I am not sure why this was not done, but aircraft department departing. When I noticed the 2 6000's coming together, I turned them away from each other. I am not sure if I had turned either aircraft at any time prior. Because of ARTS tag overlap (we do not have leader line off-set), I did not realize that I had exacerbated the situation, and turned the aircraft even further into each other. Immediately, I rectified that, but loss of separation had already occurred. Neither aircraft made any corrective actions although at least the B-767 was TCASII equipped. My normal operation would be to use diverging heading until I had altitude separation but, because of the 7000 ft overflt and the stop at 6000 ft, this may not have happened. Because I could not see the targets or ARTS tag (because of numerous ARTS tags).

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Original NASA ASRS Text

Title: ACR X SAME ALT ASSIGNED HAD LTSS FROM ACR Y. SYS ERROR.

Narrative: AT THE TIME OF THE INCIDENT I HAD A B-767, X, TO EUROPE DEPART RWY 1R AND AN ATR-42 DEPART RWY 1L. I CLBED THE B- 767 TO 10000 FT AND THE ATR-42 TO 9000 FT. THE B-767 WAS IN A CIRCLED 360 DEG HDG AND THE ATR-42 Y WAS ON A CIRCLED 340 DEG HDG. PRIOR TO THESE ACFT, I HAD A C-210 DEPART VFR THAT I DID NOT SPEAK TO FOR 6 MI. HE WAS NE OF THE ARPT AT 1500 FT, TECHNICALLY NOT IN MY AIRSPACE. N ARR HAD AN ACFT AT THE SAME ALT, MERGING, AND WE WERE TRYING TO RESOLVE THAT. I ALSO HAD A BA-31 ABOUT 20 MI NW CLRED TO 11000 FT CLBING OUT OF 4500 FT, WHICH I POINTED OUT TO N ARR AND HE COULD NOT APPROVE, SO I HAD TO VECTOR THAT ACFT FOR THE CLB. I DO NOT KNOW HOW MANY OTHER ACFT WERE ON MY FREQ. I ALSO HAD AN ACFT WITH AN INCORRECT MODE C READOUT. AT THIS POINT THINGS WERE GETTING UNTENABLE. I HAD A 7000 FT OVERFLT COME INTO MY AIRSPACE WITH NO ACCEPTANCE OF A HDOF. I STOPPED THE ATR-42 AND THE B-767 AT 6000 FT. I ALSO, SOMETIME DURING THIS TIME PERIOD, STOPPED THE DEPS TWICE. I AM NOT SURE WHY THIS WAS NOT DONE, BUT ACFT DEPT DEPARTING. WHEN I NOTICED THE 2 6000'S COMING TOGETHER, I TURNED THEM AWAY FROM EACH OTHER. I AM NOT SURE IF I HAD TURNED EITHER ACFT AT ANY TIME PRIOR. BECAUSE OF ARTS TAG OVERLAP (WE DO NOT HAVE LEADER LINE OFF-SET), I DID NOT REALIZE THAT I HAD EXACERBATED THE SIT, AND TURNED THE ACFT EVEN FURTHER INTO EACH OTHER. IMMEDIATELY, I RECTIFIED THAT, BUT LOSS OF SEPARATION HAD ALREADY OCCURRED. NEITHER ACFT MADE ANY CORRECTIVE ACTIONS ALTHOUGH AT LEAST THE B-767 WAS TCASII EQUIPPED. MY NORMAL OP WOULD BE TO USE DIVERGING HDG UNTIL I HAD ALT SEPARATION BUT, BECAUSE OF THE 7000 FT OVERFLT AND THE STOP AT 6000 FT, THIS MAY NOT HAVE HAPPENED. BECAUSE I COULD NOT SEE THE TARGETS OR ARTS TAG (BECAUSE OF NUMEROUS ARTS TAGS).

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.