On July 30, 1999, at 1130 central daylight time, a Piper J3C-65 airplane, N42378, was substantially damaged when it impacted power lines and the ground near Sanger, Texas. The airline transport rated pilot, owner and sole occupant of the airplane, sustained minor injuries. Visual meteorological conditions prevailed for the Title 14 Code of Federal Regulations Part 91 personal flight, and a flight plan was not filed. The flight originated from the Decatur Municipal Airport, Decatur, Texas, at 1120. According to the 15,000-hour pilot, the airplane had just undergone an annual inspection, and he was flying the airplane back to his private grass airstrip. While flying over fields approximately 2 miles from his airstrip, he descended to what he "thought was a safe VFR altitude." He stated that the terrain in the area is "fairly flat ranch land with no houses and no trees." The left main landing gear strut contacted a power line which extended from FM 455 to a house. Subsequently, the airplane impacted the ground approximately 50 yards from the power lines, flipped over, and came to rest inverted. Examination of the airplane by the FAA inspector revealed damage to the wings, fuselage, engine firewall, landing gear, and propeller.