Narrative:

Departure control coordinated eastbound turn through arrival airspace of air carrier X passenger jet, altitude 3000'. During this time period departure had been coordinating wbound turns through my sector. Workload was light, relaxed and I didn't actively listen to the coordination. I vectored air carrier Y, descending to 3000', north toward dulles. Air carrier X had air carrier Y in sight. Air carrier Y crew asked what the traffic ahead was. At first I didn't know what they were seeing since I removed the display of air carrier X traffic. Then it clicked and took me by surprise. The fault was with me, not listening to the departure controller's coordination, removing the display of air carrier X after coordination, since I thought it was going west instead of east.

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Original NASA ASRS Text

Title: ACR X HAD LESS THAN STANDARD SEPARATION FROM ACR Y. SYSTEM ERROR.

Narrative: DEP CTL COORDINATED EBND TURN THROUGH ARR AIRSPACE OF ACR X PAX JET, ALT 3000'. DURING THIS TIME PERIOD DEP HAD BEEN COORDINATING WBOUND TURNS THROUGH MY SECTOR. WORKLOAD WAS LIGHT, RELAXED AND I DIDN'T ACTIVELY LISTEN TO THE COORD. I VECTORED ACR Y, DSNDING TO 3000', N TOWARD DULLES. ACR X HAD ACR Y IN SIGHT. ACR Y CREW ASKED WHAT THE TFC AHEAD WAS. AT FIRST I DIDN'T KNOW WHAT THEY WERE SEEING SINCE I REMOVED THE DISPLAY OF ACR X TFC. THEN IT CLICKED AND TOOK ME BY SURPRISE. THE FAULT WAS WITH ME, NOT LISTENING TO THE DEP CTLR'S COORD, REMOVING THE DISPLAY OF ACR X AFTER COORD, SINCE I THOUGHT IT WAS GOING W INSTEAD OF E.

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.