On July 4, 1997, at 1459 eastern daylight time, a Grumman American AA-1B, N9883L, was substantially damaged when it collided with the ground during a forced landing near Culpeper, Virginia. The certificated private pilot, and the passenger were not injured. Visual meteorological conditions prevailed and a visual flight rules flight plan was filed. The personal flight was conducted under 14 CFR Part 91, and originated at Philadelphia, Pennsylvania. The flight was destined for Manassas, Virginia. According to the pilot, the airplane was in cruise flight at 2,500 feet MSL, 15 miles from his destination, when the engine sputtered. He switched fuel tanks and the engine restarted; however, the engine lost power again, and a forced landing was performed to an open field. During touchdown, the nose gear was sheared off. The pilot said he topped off the fuel tanks, and visually checked the fuel. He said there was 22 gallons of useable fuel on board, and the consumption was 6 gallons per hour. He had problems with his radios, and was unable to penetrate Dulles airspace, so he tracked from VOR's, to the west of their airspace. He had been switching fuel tanks every 1/2 hour. The airplane was examined at the accident site by a Federal Aviation Administration (FAA) Inspector. The FAA Inspector said that the fuel tanks were intact, the airplane was at a right wing low attitude, and there was no fuel visible at the filler point, which was the low point at that time. He said the left tank capillary fuel gage in the cockpit indicated a small amount of fuel. According to the FAA, the airplane owner said the pilot refueled the airplane on an incline, and that the tanks could appear full at the filler cap. The owner also stated that with the lower tank having an air pocket at the wing root area, the fuel on board could be reduced. The airplane's records showed a log out time of 95.3, and at the accident site, the Hobbs meter indicated 98.3 hours. The examination did not disclose any evidence of mechanical malfunction with the airplane or the engine.