Narrative:

Climbing through approximately FL260 on our way to FL280, ATC instructed us to leveloff at FL260. Altitude bug was not changed and I thought I heard 'slow to 260 KTS.' I slowed and continued the climb. At FL270, ATC reminded us that our last clearance was to level at FL260. I quickly descended to FL260.

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Original NASA ASRS Text

Title: A CLRNC WAS REVISED, BUT APPROPRIATE CHANGES WERE NOT MADE, ON THE MCP RESULTING IN A CONTINUED CLB TO THE ORIGINALLY CLRED ALT.

Narrative: CLBING THROUGH APPROX FL260 ON OUR WAY TO FL280, ATC INSTRUCTED US TO LEVELOFF AT FL260. ALT BUG WAS NOT CHANGED AND I THOUGHT I HEARD 'SLOW TO 260 KTS.' I SLOWED AND CONTINUED THE CLB. AT FL270, ATC REMINDED US THAT OUR LAST CLRNC WAS TO LEVEL AT FL260. I QUICKLY DSNDED TO FL260.

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.