During the takeoff roll, at about 50 knots, the airplane began to drift to the left. The pilot stated that as the airplane drifted to the left, she inadvertently tapped on the right brake, and then released the brake while adding right ailerons inputs. Corrections were made to maneuver the airplane back to the runway centerline. The right wingtip was lowered and impacted the ground 2 or 3 times. She continued to apply inputs to the right rudder pedal. The airplane nosed-over and sustained substantial damage to both wing spars and the vertical stabilizer. The second pilot stated that he didn’t know why the airplane responded as it did and was unsure if there were any malfunctions with the airplane prior to the accident. He estimated the wind to be from the left at 5 knots. A postaccident examination of the airplane by a Federal Aviation Administration inspector revealed no evidence of preaccident mechanical malfunctions or failures with the airplane that would have precluded normal operation. As the pilot was making continuous rudder pedal inputs, it is likely that she inadvertently applied the brakes.