Narrative:

I was working combined sectors, traffic was complex and heavy. I had requested sectors be split. Aircraft Y was on my frequency at FL250 landing bwi. There were 2 additional aircraft at FL250, in trail, landing bwi. ZOB activated a handoff on aircraft X climbing to FL240, a bwi satellite with no flight plan. I instructed my d-side to have ZOB turn aircraft X to a 240 degree heading. I later found out this was never accomplished. The aircraft was cleared direct mrb at 250 KTS. After several attempts to contact the aircraft, I turned aircraft Y to a 140 degree heading so I could descend (all 4 aircraft have to cross west of mrb at 15000 ft). When aircraft X finally called, I turned him to a 260 degree heading with the intention of descending him. Then thinking I was descending him, I confused data blocks and descended aircraft Y. When I realized my error, the aircraft were in opposite directions, 4 mi apart with a little over 1000 ft going away from each other.

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Original NASA ASRS Text

Title: ZDC CTLR TRANSPOSES ACFT POS, DSNDING THE WRONG ACFT IN CONFLICT WITH ANOTHER ENRTE ACFT.

Narrative: I WAS WORKING COMBINED SECTORS, TFC WAS COMPLEX AND HVY. I HAD REQUESTED SECTORS BE SPLIT. ACFT Y WAS ON MY FREQ AT FL250 LNDG BWI. THERE WERE 2 ADDITIONAL ACFT AT FL250, IN TRAIL, LNDG BWI. ZOB ACTIVATED A HDOF ON ACFT X CLBING TO FL240, A BWI SATELLITE WITH NO FLT PLAN. I INSTRUCTED MY D-SIDE TO HAVE ZOB TURN ACFT X TO A 240 DEG HDG. I LATER FOUND OUT THIS WAS NEVER ACCOMPLISHED. THE ACFT WAS CLRED DIRECT MRB AT 250 KTS. AFTER SEVERAL ATTEMPTS TO CONTACT THE ACFT, I TURNED ACFT Y TO A 140 DEG HDG SO I COULD DSND (ALL 4 ACFT HAVE TO CROSS W OF MRB AT 15000 FT). WHEN ACFT X FINALLY CALLED, I TURNED HIM TO A 260 DEG HDG WITH THE INTENTION OF DSNDING HIM. THEN THINKING I WAS DSNDING HIM, I CONFUSED DATA BLOCKS AND DSNDED ACFT Y. WHEN I REALIZED MY ERROR, THE ACFT WERE IN OPPOSITE DIRECTIONS, 4 MI APART WITH A LITTLE OVER 1000 FT GOING AWAY FROM EACH OTHER.

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.