Narrative:

My aircraft was on VOR approach to runway 15; syracuse. I was requested to descend to 2000 ft from 5000 ft. Passing through approximately 3800 ft; we encountered severe turbulence. It occurred a single time; which I then reported to ATC. Then; however; it returned as we descended lower; becoming more violent. Both my wife and I were thrown about the cabin; our autoplt was deactivated by the turbulence; and our automatic trim shut down (it may have been struck by my hand). I pulled the aircraft up; using full power; but continued descending through the bottom layer of clouds (approximately 2000 ft). Before I could bring the aircraft back; we had descended to approximately 1200 to 1300 ft; when ATC called and advised we had descended too low. I advised I was aware; as we were trying to regain control. Once outside the bottom of the cloud layer; we were able to ascend; and complete the landing. After first encountering the severe turbulence; I should have immediately disconnected the autoplt; and applied full power at that time. However; we felt the worst was over. It wasn't and we re-entered an area of even stronger turbulence. At that time; even with my seat belt on; I struck my head on the ceiling; knocking off my headphones and glasses. In retrospect; of course my seatbelt should have been tighter if we had anticipated such turbulence. Otherwise; I'm not sure we had further options other than the above.

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Original NASA ASRS Text

Title: A C210 ENCOUNTERED SEVERE TURB AT 3800 FT DSNDING. THE ACFT DSNDED TO 1200 FT BEFORE PLT REGAINED CTL.

Narrative: MY ACFT WAS ON VOR APCH TO RWY 15; SYRACUSE. I WAS REQUESTED TO DSND TO 2000 FT FROM 5000 FT. PASSING THROUGH APPROX 3800 FT; WE ENCOUNTERED SEVERE TURB. IT OCCURRED A SINGLE TIME; WHICH I THEN RPTED TO ATC. THEN; HOWEVER; IT RETURNED AS WE DSNDED LOWER; BECOMING MORE VIOLENT. BOTH MY WIFE AND I WERE THROWN ABOUT THE CABIN; OUR AUTOPLT WAS DEACTIVATED BY THE TURB; AND OUR AUTO TRIM SHUT DOWN (IT MAY HAVE BEEN STRUCK BY MY HAND). I PULLED THE ACFT UP; USING FULL POWER; BUT CONTINUED DSNDING THROUGH THE BOTTOM LAYER OF CLOUDS (APPROX 2000 FT). BEFORE I COULD BRING THE ACFT BACK; WE HAD DSNDED TO APPROX 1200 TO 1300 FT; WHEN ATC CALLED AND ADVISED WE HAD DSNDED TOO LOW. I ADVISED I WAS AWARE; AS WE WERE TRYING TO REGAIN CTL. ONCE OUTSIDE THE BOTTOM OF THE CLOUD LAYER; WE WERE ABLE TO ASCEND; AND COMPLETE THE LNDG. AFTER FIRST ENCOUNTERING THE SEVERE TURB; I SHOULD HAVE IMMEDIATELY DISCONNECTED THE AUTOPLT; AND APPLIED FULL POWER AT THAT TIME. HOWEVER; WE FELT THE WORST WAS OVER. IT WASN'T AND WE RE-ENTERED AN AREA OF EVEN STRONGER TURB. AT THAT TIME; EVEN WITH MY SEAT BELT ON; I STRUCK MY HEAD ON THE CEILING; KNOCKING OFF MY HEADPHONES AND GLASSES. IN RETROSPECT; OF COURSE MY SEATBELT SHOULD HAVE BEEN TIGHTER IF WE HAD ANTICIPATED SUCH TURB. OTHERWISE; I'M NOT SURE WE HAD FURTHER OPTIONS OTHER THAN THE ABOVE.

Data retrieved from NASA's ASRS site as of January 2009 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.