On January 21, 2020, at 1718 eastern standard time, a Grumman AA5B, N424WB, was substantially damaged when it was involved in an accident near near Tallahassee, Florida. The pilot was seriously injured, and the passenger sustained minor injuries. The airplane was registered operated under the provisions of Title 14 Code of Federal Regulations Part 91 as a personal flight. Day visual meteorological conditions prevailed, and no flight plan was filed for the cross-country flight that departed Enterprise Municipal Airport (EDN), Enterprise, Alabama and was destined for Wauchula Municipal Airport (CHN), Wauchula, Florida. The pilot stated that earlier that day they completely filled the airplane's fuel tanks, which held 52 gallons of fuel. They departed Wauchula Municipal Airport (CHN), Wauchula, Florida about 0830 and flew to Enterprise Municipal Airport (EDN), Enterprise, Alabama. They landed about 1230. About 1400, they departed for CHN. The pilot further stated that he was going to stop for fuel somewhere along the route but did not know where. The airplane was in cruise flight at an altitude of 10,500 ft, about 1.5 hours into the flight when the engine "sputtered." The pilot pushed the mixture control full forward and turned on the electric fuel pump. The engine ran better for a couple seconds but then started sputtering again. Tallahassee International Airport (TLH), Tallahassee, Florida was the closest airport, so the pilot contacted the TLH control tower and declared an emergency. Shortly thereafter, the engine experienced a total loss of power. The pilot shut off the magnetos and pulled the mixture to shut-off. Then he primed the engine a couple times and tried a restart of the engine. The engine restarted and ran for about 5 seconds before losing all power again. He added that the right fuel gauge indicated a little over a 1/4 tank (the left fuel gauge did not work). The airplane was about 7 miles from TLH at 5,000 ft when the pilot determined it would not reach the runway and set up for an off-airport landing. He saw a small sand pit that was surrounded by trees and slipped the airplane to lose altitude; however, the left wing contacted trees and impacted terrain. The pilot had no further memory of the accident. Examination of the wreckage at the accident site by a Federal Aviation Administration (FAA) inspector revealed that no evidence of fuel leakage nor odor of fuel. The inspector removed both fuel caps from the fuel tanks and did not smell or observe fuel present. Detailed examination of the engine revealed that it remained partially attached to the airframe through the lower tubular engine mounts. The engine mount tubes were impact damaged. The carburetor was impact fractured across the throttle bore and partially separated from the engine. The left magneto was also impact damaged and partially separated from the engine. The engine was removed from the airframe, suspended from a lift and partially disassembled to facilitate the examination. The crankshaft was rotated by turning the propeller and continuity of the crankshaft to the rear gears and valve train was confirmed. Compression and suction were observed from all four cylinders. The interiors of the cylinders were viewed using a lighted borescope with no anomalies noted. The throttle, mixture and carburetor heat controls were positioned fully forward. A small amount of blue liquid with an odor consistent with aviation gasoline drained from the hose from the engine driven fuel pump to the carburetor when it was disconnected. The carburetor was partially disassembled and no damage to the composite fuel float or other internal components was noted. The carburetor fuel bowl was about one-half full of blue liquid. The liquid was tested with water-finding paste and no color change of the paste was noted. The carburetor fuel inlet filter was absent of debris. About 1 tablespoon of blue liquid drained from the engine driven fuel pump when it was removed from the engine. When the end of a hose attached to the pump inlet fitting was submerged in a container of fuel and the pump actuator arm moved by hand, fuel was expelled from the pump outlet fitting. Both magnetos produced spark from all ignition leads when rotated by hand. The spark plug electrodes were worn. The Nos. 1, 2 and 4 top and bottom spark plug electrodes exhibited gray coloration. The No. 3 top and bottom spark plug electrodes exhibited dark gray coloration. The Pilot’s Operating Handbook for the airplane stated the fuel tanks held 52 gallons with 51 gallons usable, and an average fuel burn of 10.2 gallons per hour while operating the engine at 2700 rpm, in cruise flight at 10,000 feet. No pilot or aircraft logbooks were made available for review.