RedactedNarrative: Operator was attempting to load V1 onto his trailer; in the process V1 ran on top of the trailer guide rail on the downstream side. Operator then "gassed" the motor to attempt to get over the guide rail but V1 angled sideways down into the water causing it to take on water quickly. V1 flipped over and capsized, throwing the operator into the river.  He went under water for a short period of time but came up and cried out for help. He then started floating on his back and appeared to attempt to maneuver himself toward the bank as the current took him downstream. A witness ran downstream, swam out and pulled the operator to the bank.  Once onshore, the witness could not locate a pulse on the operator. Another witness began CPR until they could get him to an awaiting ambulance.  Operator was transported to White River Medical Center and pronounced dead from cardiopulmonary arrest.