Narrative:

I was cleared to 10000 ft from FL190. In the descent, I encountered moderate to severe turbulence. When I got to 10000 ft, I encountered downdrafts which caused me to go through my assigned altitude by 400 ft. I was VMC at this time, so I canceled my IFR and proceeded to the airport. There were no other aircraft in the area.

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Original NASA ASRS Text

Title: ATX CARGO TURBOPROP ENCOUNTERS MODERATE TO SEVERE TURB 15 MI NE OF MSO VOR AND OVERSHOT ENRTE ALT OF 10000 FT.

Narrative: I WAS CLRED TO 10000 FT FROM FL190. IN THE DSCNT, I ENCOUNTERED MODERATE TO SEVERE TURB. WHEN I GOT TO 10000 FT, I ENCOUNTERED DOWNDRAFTS WHICH CAUSED ME TO GO THROUGH MY ASSIGNED ALT BY 400 FT. I WAS VMC AT THIS TIME, SO I CANCELED MY IFR AND PROCEEDED TO THE ARPT. THERE WERE NO OTHER ACFT IN THE AREA.

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.