RedactedNarrative: Vessel 1 had just launched from the trailer. Operator of vessel 1 said that he had run the blower for approx. 2 minutes and turned the blower off to start the vessel. Operator said that the boat ran rough at a fast idle after starting. Operator turned the vessel off and restarted the vessel. The vessel then blew up and burst into flames. All of the occupants jumped from the vessel and swam to shore. The point of the explosion was approx. 50 feet south the east boat ramp and approx. 10 feet east of the east boat ramp. Point of rest for the burned out vessel was approx. 110 yards north-east of the east boat ramp against the north shore line.