THE PILOT LANDED ON RUNWAY 30 WITH THE WINDS FROM 230 TO 280 DEGREES AT 8 GUSTING TO 12 KNOTS. THE PILOT STATED HE COULD NOT CONTROL THE AIRCRAFT AND IT DEPARTED THE RUNWAY. ATTEMPTS BY THE PILOT TO REGAIN CONTROL OF THE AIRCRAFT WERE UNSUCCESSFUL. THE PILOT REPORTED NO MECHANICAL MALFUNCTIONS OR PROBLEMS WITH THE AIRCRAFT PRIOR TO ITS COLLISION WITH THE TERRAIN.