On September 13, 1994, about 2106 eastern daylight time, a Cessna 152, N6517M, registered to Comair Aviation Academy, collided with trees and then the ground while making a forced landing following loss of engine power at Gainesville, Florida, while on a 14 CFR Part 91 instructional flight. Visual meteorological conditions prevailed at the time and no flight plan was filed. The aircraft received substantial damage and the private-rated pilot received serious injuries. The flight last originated at Lake City, Florida, on September 13, 1994, about 2034. The pilot stated he last refueled at Tifton, Georgia. He then flew to Macon, Georgia and stopped. He did not refuel at Macon. He departed Macon en route to Lake City, Florida. According to the FAA Flight Service Station at Macon he activated his flight plan at 1530. He canceled his flight plan in the area of Lake City at 1950, according to the FAA Flight Service Station at Gainesville, Florida. The pilot stated he could not get fuel at Lake City and departed for Gainesville, Florida, at 2034. At 2041, the pilot reported to Gainesville Flight Service that he was en route from Lake City to Gainesville and that he was low on fuel. At 2105, the pilot reported to Gainesville Flight Service that the engine had quit. The pilot stated he made a forced landing in trees. Postcrash examination of the aircraft by an FAA inspector indicated the aircraft did not contain any usable fuel and that there was no reported fuel leakage from the aircraft after the accident. The aircraft operator stated the aircraft consumes 6 gallons per hour and the accident aircraft has about 37 usable gallons. The aircraft had been flown over 6 hours since the last refueling until the engine failed.