Narrative:

Aircraft #1 checked on my frequency level FL280. I climbed aircraft #1 to FL360; mistakenly believing he was in the confines of my airspace. Aircraft #2 was at FL290 and passed 3 mi behind aircraft #1. I believe this incident was caused by a rare oversight on my part.

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Original NASA ASRS Text

Title: ZNY CTLR EXPERIENCED OPERROR AT FL290 WHEN MISTAKENLY CLBING AN ACFT NOT YET IN ZNY AIRSPACE.

Narrative: ACFT #1 CHKED ON MY FREQ LEVEL FL280. I CLBED ACFT #1 TO FL360; MISTAKENLY BELIEVING HE WAS IN THE CONFINES OF MY AIRSPACE. ACFT #2 WAS AT FL290 AND PASSED 3 MI BEHIND ACFT #1. I BELIEVE THIS INCIDENT WAS CAUSED BY A RARE OVERSIGHT ON MY PART.

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.