Narrative:

Aircraft Y was an overflt at 9000 ft. I thought he was going north bound and not turning northeast. Aircraft X was cleared to 5000 ft going east bound to thv (york, PA) when aircraft Y turned northeast, separation was lost.

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Original NASA ASRS Text

Title: ZDC CTLR OVERLOOKS CHANGE IN RTE BTWN AN ENRTE JS41 THAT CONFLICTS WITH A DSNDING LJ31.

Narrative: ACFT Y WAS AN OVERFLT AT 9000 FT. I THOUGHT HE WAS GOING N BOUND AND NOT TURNING NE. ACFT X WAS CLEARED TO 5000 FT GOING E BOUND TO THV (YORK, PA) WHEN ACFT Y TURNED NE, SEPARATION WAS LOST.

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.