On September 19, 2003, approximately 1616 central daylight time, a Piper PA-12 single-engine airplane, N3336M, registered to and operated by a private individual, was substantially damaged during a forced landing following a loss of engine power near Wayne, Oklahoma. The commercial pilot, who was the sole occupant, sustained serious injuries. Visual meteorological conditions prevailed and a flight plan was not filed for the 14 Code of Federal Regulations Part 91 personal flight. The cross-country flight originated from Pacer Field Airport (5OK4), near Goldsby, Oklahoma, at 1530, and was destined for Pauls Valley Municipal Airport, near Pauls Valley, Oklahoma. On the Pilot/Operator Aircraft Accident Report (NTSB Form 6120.1/2), the 4,000-hour pilot reported that he climbed to approximately 2,500 feet, and the engine lost power. He then selected an open field and maneuvered to clear power lines. After landing in the field, the airplane impacted a pipe fence which bordered the field adjacent a highway. Subsequently, the airplane flipped over and came to rest on the west bound lane of the highway. An FAA inspector reviewed the pilot's flight log. According to entries in the flight log, the airplane was fueled to capacity (38 gallons) at 21.3 Hobbs meter time. Another 5 gallons of fuel was added at 24.5 Hobbs, and at the time of the accident the Hobbs read 26.0. According to the Lycoming Model O-320 engine Operator's Manual, at 2,450 RPM the fuel burn consumption is 10.0 gallons per hour. Based on recorded Hobbs times, the airplane was operated about 4.7 hours from the re-fuelings to the accident. At a 10 gph burn consumption, the airplane would have used about 47 gallons of fuel in 4.7 hours of operating time. Flight log entries showed 38 gal at 21.3 Hobbs and 5 gal at 24.5 Hobbs, which equals 42 gals. According to the FAA inspector who responded to the accident site, the right wing struts were bent. The engine mounts were also bent, the engine was pushed up by the lower engine cowling from impact from the pipe fence. The propeller, vertical stabilizer, rudder, and landing gear were also damaged.