Narrative:

I cleared air carrier X to FL350; I meant to clear him to FL340; air carrier Y was level at FL350. I shipped him to 78 sector. Sector 78 did not catch air carrier X climbing to wrong altitude. Supplemental information from acn 697647: air carrier X was assigned FL350 by previous controller and FL340 was in data block. Air carrier X checked on frequency; climbing to incorrect altitude. Incorrect altitude was not heard.

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Original NASA ASRS Text

Title: ZID CTLR EXPERIENCED OPERROR AT FL350 WHEN CLBING AN ACFT THROUGH OCCUPIED ALT.

Narrative: I CLRED ACR X TO FL350; I MEANT TO CLR HIM TO FL340; ACR Y WAS LEVEL AT FL350. I SHIPPED HIM TO 78 SECTOR. SECTOR 78 DID NOT CATCH ACR X CLBING TO WRONG ALT. SUPPLEMENTAL INFO FROM ACN 697647: ACR X WAS ASSIGNED FL350 BY PREVIOUS CTLR AND FL340 WAS IN DATA BLOCK. ACR X CHKED ON FREQ; CLBING TO INCORRECT ALT. INCORRECT ALT WAS NOT HEARD.

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.