According to the pilot, he started the airplane’s engine in preparation for a flight to another airport. He intended to make a 90-degree, left turn in order to taxi from the airport parking ramp directly toward the active runway. The pilot applied power and the airplane began to move forward and then began to turn to the left. After the airplane had turned to the desired heading, the pilot pushed right rudder pedal to stop the turn, but the airplane continued to turn to the left. The pilot then pushed the right wheel brakes, but the airplane did not stop. The airplane continued its turning movement to the left and the left wing and propeller impacted a snow bank on the edge of the airport parking ramp causing substantial damage to the left wing. The pilot later said that for this particular flight he probably did not have his seat positioned far forward enough for his legs to activate either the rudder pedals or the brake pedals to the full extent of their travel.