Narrative:

I was working an extremely busy sector and climbed one aircraft to an altitude that was occupied by another aircraft.

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Original NASA ASRS Text

Title: ZNY CTLR CLBED ACFT TO AN OCCUPIED ALT AND EXPERIENCED OPERROR AT 16000 FT.

Narrative: I WAS WORKING AN EXTREMELY BUSY SECTOR AND CLBED ONE ACFT TO AN ALT THAT WAS OCCUPIED BY ANOTHER ACFT.

Data retrieved from NASA's ASRS site as of January 2009 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.