Narrative:

The situation occurred at the end of the midnight shift. Traffic was heavy with the box haulers returning to the east coast. Many different things were happening, several aircraft were climbing, assigned headings, descending, etc. The medium large transport X was heavy and not climbing as fast as normal, the light transport Y well north of his filed flight plan, which caused their rtes to cross. The light transport Y was stopped at FL280 to remain below the medium large transport X when the light transport Y asked for higher, I cleared him to FL330, thinking lateral sep would exist before there was a problem. I knew this would need to be watched, I put a 6 mi polygon around the medium large transport X to ensure sep. At this time, I noticed an aircraft heading southeast that should have been northeast. I turned him to a 070 degree heading to get back on course. He was inadvertently left on a heading by the previous controller. I then observed an aircraft at FL330 turning right. His course should have been about 070 for bwz, but he was turning to about a 150 heading, right into another aircraft level at the same altitude. The conflict alert activated as the light transport Y was climbing much faster than the medium large transport X. I tried to maintain altitude, but I knew I also needed to get the two aircraft at FL330 apart. The 2 aircraft lost sep, with minimum sep at 1800', 4.7 NM. I then queried the pilot who had turned into the other traffic, and he said he had tuned in the wrong frequency for navigation. My recommendation is to always use positive sep. Even when things appear to be under control, the unexpected can happen and draw attention to something much more important. It is hard to say that this error would not have happened had all aircraft been where they should have been, and going where they should have been going. I can say I was aware of the situation, but too many other unexpected things happened all at once.

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Original NASA ASRS Text

Title: ARTCC CTLR CLIMBED LTT THROUGH ALT OF ACR MLG WITH LESS THAN STANDARD SEPARATION.

Narrative: THE SITUATION OCCURRED AT THE END OF THE MIDNIGHT SHIFT. TFC WAS HVY WITH THE BOX HAULERS RETURNING TO THE E COAST. MANY DIFFERENT THINGS WERE HAPPENING, SEVERAL ACFT WERE CLBING, ASSIGNED HDGS, DSNDING, ETC. THE MLG X WAS HVY AND NOT CLBING AS FAST AS NORMAL, THE LTT Y WELL N OF HIS FILED FLT PLAN, WHICH CAUSED THEIR RTES TO CROSS. THE LTT Y WAS STOPPED AT FL280 TO REMAIN BELOW THE MLG X WHEN THE LTT Y ASKED FOR HIGHER, I CLRED HIM TO FL330, THINKING LATERAL SEP WOULD EXIST BEFORE THERE WAS A PROB. I KNEW THIS WOULD NEED TO BE WATCHED, I PUT A 6 MI POLYGON AROUND THE MLG X TO ENSURE SEP. AT THIS TIME, I NOTICED AN ACFT HDG SE THAT SHOULD HAVE BEEN NE. I TURNED HIM TO A 070 DEG HDG TO GET BACK ON COURSE. HE WAS INADVERTENTLY L ON A HDG BY THE PREVIOUS CTLR. I THEN OBSERVED AN ACFT AT FL330 TURNING R. HIS COURSE SHOULD HAVE BEEN ABOUT 070 FOR BWZ, BUT HE WAS TURNING TO ABOUT A 150 HDG, R INTO ANOTHER ACFT LEVEL AT THE SAME ALT. THE CONFLICT ALERT ACTIVATED AS THE LTT Y WAS CLBING MUCH FASTER THAN THE MLG X. I TRIED TO MAINTAIN ALT, BUT I KNEW I ALSO NEEDED TO GET THE TWO ACFT AT FL330 APART. THE 2 ACFT LOST SEP, WITH MINIMUM SEP AT 1800', 4.7 NM. I THEN QUERIED THE PLT WHO HAD TURNED INTO THE OTHER TFC, AND HE SAID HE HAD TUNED IN THE WRONG FREQ FOR NAV. MY RECOMMENDATION IS TO ALWAYS USE POSITIVE SEP. EVEN WHEN THINGS APPEAR TO BE UNDER CTL, THE UNEXPECTED CAN HAPPEN AND DRAW ATTN TO SOMETHING MUCH MORE IMPORTANT. IT IS HARD TO SAY THAT THIS ERROR WOULD NOT HAVE HAPPENED HAD ALL ACFT BEEN WHERE THEY SHOULD HAVE BEEN, AND GOING WHERE THEY SHOULD HAVE BEEN GOING. I CAN SAY I WAS AWARE OF THE SITUATION, BUT TOO MANY OTHER UNEXPECTED THINGS HAPPENED ALL AT ONCE.

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.