Narrative:

E145 northbound at 17000 ft. B737 eastbound climbing to FL190. Issued a clearance of 16000 ft to B737 prior to loss of separation. The amended clearance was not in time. Due to bad radar data on display, I did not see that B737 was leaving 17000 ft. Therefore, B737 had to descend through 16000 ft again.

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Original NASA ASRS Text

Title: ZDC CTLR EXPERIENCED OPERROR WITH XING TFC AT 17000 FT DURING AMENDED ISSUANCE OF CORRECTIVE ACTIONS.

Narrative: E145 NBOUND AT 17000 FT. B737 EBOUND CLBING TO FL190. ISSUED A CLRNC OF 16000 FT TO B737 PRIOR TO LOSS OF SEPARATION. THE AMENDED CLRNC WAS NOT IN TIME. DUE TO BAD RADAR DATA ON DISPLAY, I DID NOT SEE THAT B737 WAS LEAVING 17000 FT. THEREFORE, B737 HAD TO DSND THROUGH 16000 FT AGAIN.

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.