On October 4, 2000, about 2200 Eastern Daylight Time, a Cessna 150M, N704ST, was substantially damaged during a forced landing in Haverford Township, Pennsylvania. The certificated private pilot was seriously injured. Night visual meteorological conditions prevailed and no flight plan had been filed for the flight that departed the Brandywine Airport (N99), West Chester, Pennsylvania. The personal flight was conducted under 14 CFR Part 91. During a telephone interview, the pilot stated he intended to fly to the New Garden Airport, Toughkenaman, Pennsylvania, which was located about 15 miles southwest of N99; however, he was unable to locate the airport and elected to return to N99. The pilot stated that he had difficulty finding N99, and while searching for the runway, "the airplane ran out of gas." The pilot performed a forced landing into trees, and the airplane came to rest about 150 feet into a quarry. As of April 2000, the airplane had not been recovered. The pilot stated he departed with about 7 or 8 gallons of fuel on board; however, he was not certain how long he had been in flight. Additionally, the pilot said he did not experience any mechanical problems during the flight. The airplane's most recent annual inspection was performed on September 8, 1999, and the pilot reported the airplane had been flown "a few hours" since the inspection. The pilot's most recent application for a Federal Aviation Administration medical certificate, was processed on July 23, 1987. At that time he reported 200 hours of total flight experience.