Narrative:

Air carrier X at FL350, wbound on J96, requested climb to FL390. I issued traffic to air carrier X and told him to stand by. I had traffic, 15 or more aircraft on frequency with 3 or more being sequenced for phx arrival, 1 unknown aircraft on my frequency and climbing aircraft from phx. After air carrier X passed eastbound traffic at FL370, I climbed air carrier X to FL390, the diverted my attention to other traffic sits. I looked back to air carrier X and saw that he was in confliction with air carrier Y who was eastbound on J96, conflict alert went off at this time also. I had air carrier X stop climb and turn left to 160 degrees and air carrier Y turn left to 350 degrees. The 2 aircraft passed by about 4.6 mi and 1600 ft. The sector overlying this sector had been closed about 30 mins earlier because the supervisor did not think there was enough traffic to justify having it open. If the sector above had been open I feel this error would not have occurred. Air carrier Y would have been in that sector and I would not have been able to climb air carrier X without calling the sector above. For some reason I did not have a flight strip on air carrier Y. Also this was the first day for using new flight strip printers that are unable to print in red and stripes were difficult to read (not being accustomed to the new format).

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Original NASA ASRS Text

Title: ARTCC RADAR CTLR CLBED AN ACR A320 THROUGH AN ALT OCCUPIED BY AN OPPOSITE DIRECTION ACR DC10. POTENTIAL CONFLICT LTSS WAS SEEN BY THE CTLR AT THE SAME TIME THE CONFLICT ALERT ACTIVATED. BOTH ACFT WERE TURNED, BUT NOT BEFORE SEPARATION WAS LOST. CTLR HAD ABOUT 15 ACFT ON HIS FREQ WHEN THIS OCCURRED.

Narrative: ACR X AT FL350, WBOUND ON J96, REQUESTED CLB TO FL390. I ISSUED TFC TO ACR X AND TOLD HIM TO STAND BY. I HAD TFC, 15 OR MORE ACFT ON FREQ WITH 3 OR MORE BEING SEQUENCED FOR PHX ARR, 1 UNKNOWN ACFT ON MY FREQ AND CLBING ACFT FROM PHX. AFTER ACR X PASSED EBOUND TFC AT FL370, I CLBED ACR X TO FL390, THE DIVERTED MY ATTN TO OTHER TFC SITS. I LOOKED BACK TO ACR X AND SAW THAT HE WAS IN CONFLICTION WITH ACR Y WHO WAS EBOUND ON J96, CONFLICT ALERT WENT OFF AT THIS TIME ALSO. I HAD ACR X STOP CLB AND TURN L TO 160 DEGS AND ACR Y TURN L TO 350 DEGS. THE 2 ACFT PASSED BY ABOUT 4.6 MI AND 1600 FT. THE SECTOR OVERLYING THIS SECTOR HAD BEEN CLOSED ABOUT 30 MINS EARLIER BECAUSE THE SUPVR DID NOT THINK THERE WAS ENOUGH TFC TO JUSTIFY HAVING IT OPEN. IF THE SECTOR ABOVE HAD BEEN OPEN I FEEL THIS ERROR WOULD NOT HAVE OCCURRED. ACR Y WOULD HAVE BEEN IN THAT SECTOR AND I WOULD NOT HAVE BEEN ABLE TO CLB ACR X WITHOUT CALLING THE SECTOR ABOVE. FOR SOME REASON I DID NOT HAVE A FLT STRIP ON ACR Y. ALSO THIS WAS THE FIRST DAY FOR USING NEW FLT STRIP PRINTERS THAT ARE UNABLE TO PRINT IN RED AND STRIPES WERE DIFFICULT TO READ (NOT BEING ACCUSTOMED TO THE NEW FORMAT).

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.