On July 25, 1994 about 2215 eastern daylight time, N5647A, a Cessna 172 airplane, a personal flight, collided with trees during the initial takeoff climb from runway 28 at Block Island State Airport, Rhode Island. The non-instrument rated private pilot and three passengers received minor injuries. The airplane was substantially damaged. Instrument meteorological conditions existed, and no flight plan was filed. The destination was Windsor Locks, Connecticut. The flight was operated under 14 CFR Part 91. According to the pilot's statement, "Fog layer was by my estimate to be approximately 100 to 200 feet . . . I climbed out with a half-tank of fuel and four people at 60 mph indicated, and just did not have enough performance . . . The next thing I knew I saw bushes in front. I pulled back to lessen the impact and tried to hit the tail first. The airplane spun approximately 180 degrees after impact." During an interview with the FAA, the pilot reported that the fog at the airport was about 60 to 100 feet thick. He indicated that after takeoff, the vaccum gage didn't seem to work right and that because of the lack of climbing performance, he raised the flaps, which were set at 10 degrees. None of the passengers reported a problem with the airplane during the takeoff. One passenger reported the takeoff occurred in heavy fog. A witness reported heavy fog at the time of the accident. He stated the airplane took off, went into the fog, and disappeared. Shortly thereafter he heard the airplane land into trees (beyond the runway end). The FAA examination of the airplane revealed no mechanical malfunctions. The propeller blades were curled. The aircraft estimated to be about 75 pounds over gross weight.