On July 15, 2021, about 1000 eastern daylight time, a De Havilland Canada DHC-1 Chipmunk X, N47YC, was substantially damaged when it was involved in an accident at Lebanon, Tennessee. The commercial pilot was seriously injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. The pilot reported that he intended to fly the airplane from Fall Creek Field Airport (TN96) in Lebanon, to Lebanon Municipal Airport (M54). After uneventful ground operations, he took off on runway 18 with the fuel selector positioned to the left fuel tank, which was full. He reported that the right fuel tank was half-full. During the initial climb, at an altitude between 100 and 150 ft above the ground, the engine suddenly lost all power; however, it did not seize. The pilot was unable to return to the airport and prepared for a forced landing. He maneuvered the airplane between trees, and the airplane descended into the trees and impacted the ground. The Federal Aviation Administration inspector who responded to the accident site reported that both wings and the fuselage were substantially damaged. The leading edge of the right wing sustained impact damage that penetrated and ruptured the rubberized bladder fuel tank; no fuel remained in the tank. The left-wing fuel tank was undamaged and contained an adequate supply of fuel. The cockpit fuel selector was found in the RIGHT tank position. No contamination or obstructions were found in the fuel system. The De Havilland Gipsy Major engine was examined at an aircraft salvage facility after the accident. The engine remained attached to the airframe. There was impact damage to the propeller, engine mount, firewall, and the lower and left sides of the engine. The engine was turned through by manually rotating the propeller. The engine turned freely through 360° with no binding or unusual noise evident. The two forward cylinders did not show compression or suction when the engine was rotated. Further examination revealed impact damage to the rocker covers and internal components in the cylinder heads. A lighted borescope was then inserted inside both cylinders. The pistons moved up and down normally, and valve action was correct. There were no holes or damage to the pistons or valves. The aft two cylinders were undamaged. When the engine was rotated, compression and suction were observed on both aft cylinders. The dual engine-driven fuel pumps were removed for examination. Fuel was found inside the lines from the fuel pumps to the carburetor. The fuel strainers were opened; both strainers were full of fuel, and the screens were clean and unobstructed. The lever-action pumps functioned normally when operated by hand. The carburetor was examined on the engine. All cockpit controls were connected and exhibited full travel when manipulated by hand. The suction oil filter was removed for examination. The unit contained oil. The screen was removed, and no particulates or contamination were observed. The spark plugs were removed for examination. The electrodes were normal in wear and dark in color when compared to a Champion Check-a-Plug chart. The magnetos were removed and tested by rotating with a power drill. Both magnetos produced spark when rotated. The fixed-pitch Fairey Aviation Co. Ltd. two-bladed aluminum propeller remained securely attached to the engine. The propeller spinner was undamaged. The propeller blades exhibited minor impact damage with slight aft bending at the tips. There was no chordwise scratching on the surfaces of the blades or leading-edge damage.