Narrative:

Inadvertent climb into type B. Assumed I was outside it after 20 mi from den. Early am, not thinking as clearly as I should. No conflicts. I descended as soon as I realized problem. No contact with ATC.

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Original NASA ASRS Text

Title: A C182 PLT CLBS INTO THE DEN CLASS B ON AN EARLY MORNING FLT. SAYS HE WASN'T THINKING CLRLY.

Narrative: INADVERTENT CLB INTO TYPE B. ASSUMED I WAS OUTSIDE IT AFTER 20 MI FROM DEN. EARLY AM, NOT THINKING AS CLRLY AS I SHOULD. NO CONFLICTS. I DSNDED AS SOON AS I REALIZED PROB. NO CONTACT 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.