Narrative:

While climbing, we had been cleared to 12000 ft. Callouts at 11000 ft were made but we climbed to 12500 ft before realizing our mistake and immediately descended to 12000 ft. At the exact time we got back down to 12000 ft we were cleared to 17000 ft. This all happened at the time of being handed off from one center to another.

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Original NASA ASRS Text

Title: A CPR JET FLC CLBS 500 FT ABOVE ITS ASSIGNED ALT WHILE ATTEMPTING A LEVELOFF AT 12000 FT W OF LAN, MI.

Narrative: WHILE CLBING, WE HAD BEEN CLRED TO 12000 FT. CALLOUTS AT 11000 FT WERE MADE BUT WE CLBED TO 12500 FT BEFORE REALIZING OUR MISTAKE AND IMMEDIATELY DSNDED TO 12000 FT. AT THE EXACT TIME WE GOT BACK DOWN TO 12000 FT WE WERE CLRED TO 17000 FT. THIS ALL HAPPENED AT THE TIME OF BEING HANDED OFF FROM ONE CTR TO ANOTHER.

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.