Narrative:

I was working sector 16 during the morning rush (approximately 19 aircraft). I had 4 potential conflicts I was trying to resolve. I had taken action on 3, but could not talk to both aircraft with the fourth. The 2 aircraft that eventually led to the operational error were air carrier X flying from the south to the north, and aircraft Y flying from the east to the west. I recognized these 2 aircraft were in potential conflict and turned aircraft Y 20 degrees to the left. I thought air carrier X was flying J20 and this heading would put aircraft Y approximately 13 mi in trail. I then tried to contact both aircraft at the opposite end of my sector. The supervisor noticed I was getting busy and put a third person on position. While we were transitioning to operating with the additional controller, I noticed air carrier X turning right on J13 (approximately a 40 degree turn). I tried contacting the pilot and tried turning him 30 degrees left -- no response. I then cleared aircraft Y an additional 20 degrees left. He took the turn, but separation was lost. Factors I believed led to operational error: 1) extremely complex sector (many shelves and conflicts). 2) language problem with air carrier X. 3) distraction from another potential situation worked by other controllers and no coordination. 4) too many aircraft in the sector. 5) lack of awareness on my part with the route of flight on air carrier X.

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Original NASA ASRS Text

Title: DURING THE PROCESS OF ADDING ANOTHER CTLR TO EFFECT COORD FOR THE SECTOR, A ZDV RADAR CTLR LOSES SEPARATION BTWN 2 ACFT IN CRUISE, BUT CONVERGING.

Narrative: I WAS WORKING SECTOR 16 DURING THE MORNING RUSH (APPROX 19 ACFT). I HAD 4 POTENTIAL CONFLICTS I WAS TRYING TO RESOLVE. I HAD TAKEN ACTION ON 3, BUT COULD NOT TALK TO BOTH ACFT WITH THE FOURTH. THE 2 ACFT THAT EVENTUALLY LED TO THE OPERROR WERE ACR X FLYING FROM THE S TO THE N, AND ACFT Y FLYING FROM THE E TO THE W. I RECOGNIZED THESE 2 ACFT WERE IN POTENTIAL CONFLICT AND TURNED ACFT Y 20 DEGS TO THE L. I THOUGHT ACR X WAS FLYING J20 AND THIS HDG WOULD PUT ACFT Y APPROX 13 MI IN TRAIL. I THEN TRIED TO CONTACT BOTH ACFT AT THE OPPOSITE END OF MY SECTOR. THE SUPVR NOTICED I WAS GETTING BUSY AND PUT A THIRD PERSON ON POS. WHILE WE WERE TRANSITIONING TO OPERATING WITH THE ADDITIONAL CTLR, I NOTICED ACR X TURNING R ON J13 (APPROX A 40 DEG TURN). I TRIED CONTACTING THE PLT AND TRIED TURNING HIM 30 DEGS L -- NO RESPONSE. I THEN CLRED ACFT Y AN ADDITIONAL 20 DEGS L. HE TOOK THE TURN, BUT SEPARATION WAS LOST. FACTORS I BELIEVED LED TO OPERROR: 1) EXTREMELY COMPLEX SECTOR (MANY SHELVES AND CONFLICTS). 2) LANGUAGE PROB WITH ACR X. 3) DISTR FROM ANOTHER POTENTIAL SIT WORKED BY OTHER CTLRS AND NO COORD. 4) TOO MANY ACFT IN THE SECTOR. 5) LACK OF AWARENESS ON MY PART WITH THE RTE OF FLT ON ACR X.

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.