PLT MISCALCULATES HIS FUEL FOR A LONG XCOUNTRY FLT; RESULTING IN DEPLETED TANKS ON BASE TO FINAL AT SQL. FORCED LNDG; SHORT OF THE FIELD; CAUSED ACFT TO FLIP OVER.

Narrative

ON SAT; AT APPROX XA30 PM CESSNA T210N CENTURION EXPERIENCED A PWR LOSS AND LANDED IN THE MARSHLANDS SHORT OF RWY 30 AT SAN CARLOS ARPT (SQL); CA. THE ACFT WAS RETURNING TO SQL FROM TRUCKEE; WHERE IT HAD DEPARTED APPROX 1 HR 10 MINS EARLIER. PRIOR TO DEP; BOTH FUEL GAUGES AND FUEL TOTALIZER INDICATED THAT FUEL QUANTITY WAS OVER HALF FULL; MORE THAN SUFFICIENT FOR THE INTENDED FLT PLUS APPLICABLE RESERVES. DURING THE FLT; THE PLT MONITORED FUEL CONSUMPTION IN RELATION TO THE PROGRESS OF THE FLT AND DETERMINED THAT FLT COULD BE CONCLUDED WITH FUEL ONBOARD. WHILE ON BASE LEG FOR SQL RWY 30; AT AN ALT OF APPROX 900 FT; PLT WAS CONDUCTING HIS PRE-LNDG CHKLIST AND DETERMINED THAT APPROX 45-60 MINS OF FUEL REMAINED ONBOARD. AS MIXTURE WAS MOVED TO 'FULL RICH;' THE ENG QUIT. THE PLT ATTEMPTED TO RESTART THE ENG BUT TO NO AVAIL. THE PLT ADVISED SQL ATCT OF THE 'ENG OUT' EMER AND WAS CLRED TO LAND. ATCT RPTED SUBSTANTIAL QUARTERING HEADWINDS -- OVER 20 KTS AT TIMES. DUE TO THE SUBSTANTIAL WINDS; THE PLT HAD SOME DOUBTS AS TO WHETHER THE ACFT WOULD MAKE THE ARPT AND ELECTED TO MAKE A PRECAUTIONARY LNDG IN A FIELD ABOUT 400 YARDS SHORT OF THE RWYS. JUST PRIOR TO TOUCHDOWN; THE PLT BANKED THE ACFT TO THE L TO FLY DIRECTLY INTO THE WIND AND BECAUSE THE LNDG AREA LOOKED MORE LEVEL TO THE L. THE LNDG WAS UNEVENTFUL UNTIL THE NOSEWHEEL STRUCK A CONCRETE MASS THAT WAS COVERED WITH TOPSOIL. THE NOSEWHEEL COLLAPSED AND THE ACFT FLIPPED OVER. NEITHER THE PLT NOR HIS PAX WERE INJURED AND THE ACFT SUSTAINED ONLY MINOR DAMAGE.