THE PILOT STARTED THE TAKEOFF ROLL ON THE ICY RUNWAY. HE SAID, 'AT APPROXIMATELY 70 KNOTS (AT ROTATION) THE AIRCRAFT STARTED TO DRIFT LEFT AND BOTH STEERING AND RUDDER WERE INEFFECTIVE IN STOPPING THE DRIFT. THE LEFT PROPELLER STRUCK THE ICE BANK.' THE AIRPLANE YAWED TO THE LEFT AND DEPARTED THE RUNWAY, COLLAPSING THE LANDING GEAR. THE WIND WAS APPROXIMATELY 45 DEGREES FROM THE RIGHT AT AN ESTIMATED 4 KNOTS. THE EDGES OF THE RUNWAY HAD SNOW BANKS APPROXIMATELY 2 FEET HIGH. AN EXAMINATION BY THE FAA OF THE AIRPLANE RUDDER AND BRAKING SYSTEMS FOUND NO DISCREPANCIES.