Maine officials are investigating a personal watercraft explosion that launched a man 20 feet through the air and sent the engine covering flying more than 60 feet. The Maine Warden Service says the explosion occurred when 31-year-old Karl Marchionda, of Danvers, MA, attempted to start the watercraft after filling it with about 10 gallons of fuel at Long Lake Marina on Long Lake in Naples. Authorities say Marchionda landed face-first on a dock and was taken to Bridgton Hospital with non-life-threatening injuries. Warden Neal Wykes said a mechanism securing the fuel lines to the gas tank had come loose, allowing fuel to enter the watercraft hull. He said that the gas fumes apparently ignited when the machine was started. The marina owner put out the fire with an extinguisher.