Narrative:

While ascending on an IFR flight plan to omh, I was checking WX, due to a line of severe thunderstorms just west of my route, when I climbed through my assigned altitude of 8000 ft. I was at 9000 ft, thinking I was cleared to 10000 ft, my original desired altitude. ATC called me at the same time I realized that I was only assigned 8000 ft. I apologized to ATC communicating I thought I was going to 10000 ft. ATC granted my request to go to 10000 ft. A combination of factors contributed to this problem, including checking WX while in my climb, and thinking that I had been cleared to 10000 ft when it was only 8000 ft. Writing this information down and not checking WX until I am at my assigned cruise altitude would have helped to prevent this occurrence from happening.

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Original NASA ASRS Text

Title: MO20 PLT CLBED THROUGH HIS ASSIGNED ALT OF 8000 FT BELIEVING HE HAD BEEN CLRED TO 10000 FT.

Narrative: WHILE ASCENDING ON AN IFR FLT PLAN TO OMH, I WAS CHKING WX, DUE TO A LINE OF SEVERE TSTMS JUST W OF MY RTE, WHEN I CLBED THROUGH MY ASSIGNED ALT OF 8000 FT. I WAS AT 9000 FT, THINKING I WAS CLRED TO 10000 FT, MY ORIGINAL DESIRED ALT. ATC CALLED ME AT THE SAME TIME I REALIZED THAT I WAS ONLY ASSIGNED 8000 FT. I APOLOGIZED TO ATC COMMUNICATING I THOUGHT I WAS GOING TO 10000 FT. ATC GRANTED MY REQUEST TO GO TO 10000 FT. A COMBINATION OF FACTORS CONTRIBUTED TO THIS PROB, INCLUDING CHKING WX WHILE IN MY CLB, AND THINKING THAT I HAD BEEN CLRED TO 10000 FT WHEN IT WAS ONLY 8000 FT. WRITING THIS INFO DOWN AND NOT CHKING WX UNTIL I AM AT MY ASSIGNED CRUISE ALT WOULD HAVE HELPED TO PREVENT THIS OCCURRENCE FROM HAPPENING.

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.