On June 11, 1995, at 2000 eastern daylight time, a Beech Be- 33, N943T, was substantially damaged during a precautionary landing near Franklin Township, Pennsylvania. The private pilot was not injured. Visual meteorological conditions (VMC) prevailed, for the personal flight that departed New Haven, Connecticut, about 1800. An instrument flight plan had been filed for the flight conducted under 14 CFR Part 91. In the NTSB Form 6120.1/2, and during a telephone interview, the pilot stated that he received a weather briefing from the Bridgeport Automated Flight Service Station, at 1600, and an update from the Bangor Flight Service Station (FSS), at 1700. He was informed of a line of thunderstorms moving through his destination, Hagerstown, Pennsylvania, during both briefings. The pilot stated that he departed the Tweed-New Haven Airport (HVN), at 1800, and due to VMC at the departure airport, he did not activate his IFR flight plan. He climbed to 8,500 feet, and proceeded direct to Hagerstown using Loran navigation. While enroute, he contacted Boston Flight Watch and received a weather update. When the visibility decreased near Harrisburg, Pennsylvania, the pilot climbed to 10,500 feet, to stay above the haze level. He also navigated around cloud build ups north and south of his course. The pilot stated that about 30 miles north of his destination, he saw dark clouds in all quadrants, and decided to executed a 180 degree turn. During the turn, the airplane entered a cloud build up, experienced strong positive and negative load forces, and heavy precipitation. The pilot stated he was unable to hold heading or altitude. He lowered the landing gear and reduced airspeed for better controllability. When the airplane exited the clouds, the pilot was able to see the ground below, but was unsure of his exact location. He stated that he did not want to reenter the clouds, and entered an "emergency spiral descent." He then elected to make a precautionary landing on a dirt road. The pilot stated that he retracted the landing gear prior to touch down to avoid cartwheeling. During the landing roll, the airplane veered off the left side of the road. A review of aeronautical navigation charts revealed there were over 25 operating airports, within a 20 nautical mile radius of Harrisburg.