Narrative:

Had an aircraft X southbound filed hittr..inpin..dhp at FL350. Accepted handoff of aircraft Y at FL340 requesting FL360 heading northwestbound. Forgot about aircraft X route; thinking he was a flight that turned south instead of east. Climbed aircraft Y to FL360. Controller working sector under my airspace asked if I had climbed the aircraft Y. Conflict alert went off and I noticed the head-on situation. Aircraft Y was at FL344 at the time and I told him to descend back down. I issued aircraft X an immediate 45 degree right turn. Called traffic to both aircraft. RA on aircraft X instructed them to descend. Lost separation. Both aircraft reported the other in sight. When vertical and lateral separation was re-established; cleared aircraft X and aircraft Y back on course.

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Original NASA ASRS Text

Title: ZJX Controller experienced an operational error at FL350 when issuing a climb clearance to one aircraft; failing to note the filed route of a conflicting aircraft; resulting in a head on conflict; corrective action was too late to secure separation.

Narrative: Had an Aircraft X southbound filed HITTR..INPIN..DHP at FL350. Accepted handoff of Aircraft Y at FL340 requesting FL360 heading northwestbound. Forgot about Aircraft X route; thinking he was a flight that turned south instead of east. Climbed Aircraft Y to FL360. Controller working sector under my airspace asked if I had climbed the Aircraft Y. Conflict Alert went off and I noticed the head-on situation. Aircraft Y was at FL344 at the time and I told him to descend back down. I issued Aircraft X an immediate 45 degree right turn. Called traffic to both aircraft. RA on Aircraft X instructed them to descend. Lost separation. Both aircraft reported the other in sight. When vertical and lateral separation was re-established; cleared Aircraft X and Aircraft Y back on course.

Data retrieved from NASA's ASRS site as of April 2012 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.