Narrative:

We leveled off at cruise at 12000 ft en route to the ukn VOR. We did our normal WX briefings and noticed no unusual WX reported until msp which was our final destination. Our radar was painting an area of green just northeast of the ukn VOR. About 5 mi from the VOR we noticed an increase in airspeed and the aircraft climbed. We pulled the power back to flight idle and pitched down, yet we were climbing 2000 FPM. We ended up 700 ft above our assigned altitude, and then we encountered about 15 seconds of hail. The flight was surprisingly smooth and no significant WX was encountered again until we got to msp where we were painting thunderstorms. We immediately returned to our assigned altitude and continued. The problem was WX related and radar failed to give any signs of its presence. We gave the report to ZMP so they could pass along the word to anyone else in the area. Supplemental information from acn 319321: as we flew along the southwest side of the cell we encountered severe hail for approximately 15 seconds followed by an intense updraft of approximately 2000 FPM. 1 min later, we were in VMC conditions and noticed the aircraft had sustained damage to its leading edge. All of the aircraft's engine indications appeared normal so we continued to our destination.

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Original NASA ASRS Text

Title: COMMUTER ACFT ENCOUNTERS SEVERE UPDRAFT AND HAIL AT CRUISE.

Narrative: WE LEVELED OFF AT CRUISE AT 12000 FT ENRTE TO THE UKN VOR. WE DID OUR NORMAL WX BRIEFINGS AND NOTICED NO UNUSUAL WX RPTED UNTIL MSP WHICH WAS OUR FINAL DEST. OUR RADAR WAS PAINTING AN AREA OF GREEN JUST NE OF THE UKN VOR. ABOUT 5 MI FROM THE VOR WE NOTICED AN INCREASE IN AIRSPD AND THE ACFT CLBED. WE PULLED THE PWR BACK TO FLT IDLE AND PITCHED DOWN, YET WE WERE CLBING 2000 FPM. WE ENDED UP 700 FT ABOVE OUR ASSIGNED ALT, AND THEN WE ENCOUNTERED ABOUT 15 SECONDS OF HAIL. THE FLT WAS SURPRISINGLY SMOOTH AND NO SIGNIFICANT WX WAS ENCOUNTERED AGAIN UNTIL WE GOT TO MSP WHERE WE WERE PAINTING TSTMS. WE IMMEDIATELY RETURNED TO OUR ASSIGNED ALT AND CONTINUED. THE PROB WAS WX RELATED AND RADAR FAILED TO GIVE ANY SIGNS OF ITS PRESENCE. WE GAVE THE RPT TO ZMP SO THEY COULD PASS ALONG THE WORD TO ANYONE ELSE IN THE AREA. SUPPLEMENTAL INFO FROM ACN 319321: AS WE FLEW ALONG THE SW SIDE OF THE CELL WE ENCOUNTERED SEVERE HAIL FOR APPROX 15 SECONDS FOLLOWED BY AN INTENSE UPDRAFT OF APPROX 2000 FPM. 1 MIN LATER, WE WERE IN VMC CONDITIONS AND NOTICED THE ACFT HAD SUSTAINED DAMAGE TO ITS LEADING EDGE. ALL OF THE ACFT'S ENG INDICATIONS APPEARED NORMAL SO WE CONTINUED TO OUR DEST.

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.