On February 12, 2002, about 1500 Pacific standard time, a Piper PA-24-180, N7004P, registered to and operated by the pilot as a 14 CFR Part 91 personal flight, sustained substantial damage when it collided with a fence and trees at the Scappoose Industrial Airpark, Scappoose, Oregon. Visual meteorological conditions prevailed at the time and no flight plan was filed. The private pilot received minor injuries and the passenger was fatally injured. During a telephone interview and subsequent written statement, the pilot reported that after fueling, attempts to start the engine with the electric starter were unsuccessful, therefore, he decided to hand prop the engine. The pilot stated that he "pulled the prop through six to seven times" to purge the fuel in the cylinders. After this was completed, he instructed his passenger, seated in the right seat, to turn on the master switch. The pilot then turned the magnetos to the both on position, enriched the mixture, and opened the throttle one-quarter to three-eighths of an inch. The pilot also instructed his passenger on the operation of the "T" handle brake system, which had to be pushed in for the Johnson brake bar to work. The pilot stated that he then "pushed on the cowl to verify the brake was set. It was. I pulled the prop, and the engine instantly started". The pilot then started to walk around the wing when the engine RPM increased to high RPM and the airplane began to move forward. The wing knocked the pilot down and the airplane continued to travel across the ramp toward the runway. The aircraft crossed the runway and a taxiway before colliding with a fence and subsequently trees in a park on the west side of the airport. The aircraft fuselage came to rest against a tree. Both wings and the left horizontal stabilizer separated from the fuselage. The pilot stated that he does not know how the brake could have been released, and he reported no mechanical malfunction or failure on the NTSB Pilot/Operator Aircraft Accident Report Form 6120.1/2. No ground tie down ropes or wheel chocks were used. An automated weather observation at Scappoose reported at 1453, clear skies with 10 miles visibility and wind from 330 degrees at 3 knots. Witnesses at the fuel pumps, reported to a Scappoose Police Department Officer, that the aircraft was traveling approximately 70 to 80 miles per hour when it collided with the fence and trees.