Narrative:

In light and occasional moderate turbulence with very light rain under INS, I was jolted like hit with a truck, knocking everything out of the flight bag and my pockets, and knocking my head on the aircraft ceiling, though the seat belt was fastened tightly. There was some stunning with minor bleeding. As a result, I was suddenly at 8500'. This caused no problem, except spending the next 15 mins getting the cockpit in order. There were no thunderstorms in the area, nor am I aware of any to follow. It was the hardest jolt other than a similar jolt in an isolated early forming cumulus 20 yrs ago. The remainder of the flight was uneventful.

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Original NASA ASRS Text

Title: PLT OF SMT WING IN CRUISE AT NIGHT AT 8000' HAD SEVERE JOLT THAT HIT HIS HEAD AGAINST ROOF. PERSONAL INJURY. DEBRIS SCATTERED OVER COCKPIT.

Narrative: IN LIGHT AND OCCASIONAL MODERATE TURB WITH VERY LIGHT RAIN UNDER INS, I WAS JOLTED LIKE HIT WITH A TRUCK, KNOCKING EVERYTHING OUT OF THE FLT BAG AND MY POCKETS, AND KNOCKING MY HEAD ON THE ACFT CEILING, THOUGH THE SEAT BELT WAS FASTENED TIGHTLY. THERE WAS SOME STUNNING WITH MINOR BLEEDING. AS A RESULT, I WAS SUDDENLY AT 8500'. THIS CAUSED NO PROB, EXCEPT SPENDING THE NEXT 15 MINS GETTING THE COCKPIT IN ORDER. THERE WERE NO TSTMS IN THE AREA, NOR AM I AWARE OF ANY TO FOLLOW. IT WAS THE HARDEST JOLT OTHER THAN A SIMILAR JOLT IN AN ISOLATED EARLY FORMING CUMULUS 20 YRS AGO. THE REMAINDER OF THE FLT WAS UNEVENTFUL.

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.