Narrative:

Cga X, departure from dca, was at FL280 requesting FL390. Cga Y was descending from FL350 to FL310. Both aircraft were swbnd. Cga Y was approximately 8 mi left of cga X. I thought I had assigned cga Y a 240 degree heading to parallel cga X while climbing through cga Y's altitude; however I said heading 340, and by the time I realized that cga Y was in a right turn and stopped his climb at FL290, plus turned him back left to a 240 degree heading, the aircraft reached FL297 and was 4.2 mi from cga X. At this point cga X was at FL312. Human error on my part was the primary cause of loss of sep in that I was not aware I had said heading 340 when I meant to use heading 240.

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Original NASA ASRS Text

Title: ACFT WAS ISSUED AN ERRONEOUS HEADING THAT RESULTED IN LESS THAN STANDARD SEPARATION WITH ANOTHER ACFT.

Narrative: CGA X, DEP FROM DCA, WAS AT FL280 REQUESTING FL390. CGA Y WAS DSNDING FROM FL350 TO FL310. BOTH ACFT WERE SWBND. CGA Y WAS APPROX 8 MI L OF CGA X. I THOUGHT I HAD ASSIGNED CGA Y A 240 DEG HDG TO PARALLEL CGA X WHILE CLBING THROUGH CGA Y'S ALT; HOWEVER I SAID HDG 340, AND BY THE TIME I REALIZED THAT CGA Y WAS IN A RIGHT TURN AND STOPPED HIS CLB AT FL290, PLUS TURNED HIM BACK LEFT TO A 240 DEG HDG, THE ACFT REACHED FL297 AND WAS 4.2 MI FROM CGA X. AT THIS POINT CGA X WAS AT FL312. HUMAN ERROR ON MY PART WAS THE PRIMARY CAUSE OF LOSS OF SEP IN THAT I WAS NOT AWARE I HAD SAID HDG 340 WHEN I MEANT TO USE HDG 240.

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.