Narrative:

I was on a part 135 cargo flight. I was assigned 5000 ft as my altitude. Due to inattn, I found myself at 5900 ft and was questioned by the controller. The deviation was unintentional and just a plain mistake. I immediately went back down to 5000 ft. I will pay closer attention on cold mornings when the climb rate is increased.

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Original NASA ASRS Text

Title: C402 PLT ON CARGO FLT CLBS ABOVE ASSIGNED ALT. DEP CTLR QUERIES PLT WHO DSNDS TO PROPER ALT.

Narrative: I WAS ON A PART 135 CARGO FLT. I WAS ASSIGNED 5000 FT AS MY ALT. DUE TO INATTN, I FOUND MYSELF AT 5900 FT AND WAS QUESTIONED BY THE CTLR. THE DEV WAS UNINTENTIONAL AND JUST A PLAIN MISTAKE. I IMMEDIATELY WENT BACK DOWN TO 5000 FT. I WILL PAY CLOSER ATTN ON COLD MORNINGS WHEN THE CLB RATE IS INCREASED.

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.