Narrative:

Thought clearance was to 10000 ft. At 10800 ft, realized clearance was to 11000 ft. Climbed to 11000 ft. Do not believe any altitude problem occurred with ATC.

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Original NASA ASRS Text

Title: F100 CREW HAD AN ALT OVERSHOOT IN C90 CLASS E AIRSPACE.

Narrative: THOUGHT CLRNC WAS TO 10000 FT. AT 10800 FT, REALIZED CLRNC WAS TO 11000 FT. CLBED TO 11000 FT. DO NOT BELIEVE ANY ALT PROB OCCURRED WITH ATC.

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.