Narrative:

During climb, aircraft fuel was somewhat out of balance. I was securing the fuel balancing while the first officer was looking at charts. We were cleared to FL230. Altitude alerter did not go off (or we did not hear it). Was at 23600 ft when we realized what happened. Descended back to FL230. No known conflict.

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Original NASA ASRS Text

Title: ALTDEV. OVERSHOOT ON CLB.

Narrative: DURING CLB, ACFT FUEL WAS SOMEWHAT OUT OF BAL. I WAS SECURING THE FUEL BALANCING WHILE THE FO WAS LOOKING AT CHARTS. WE WERE CLRED TO FL230. ALT ALERTER DID NOT GO OFF (OR WE DID NOT HEAR IT). WAS AT 23600 FT WHEN WE REALIZED WHAT HAPPENED. DSNDED BACK TO FL230. NO KNOWN CONFLICT.

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.