On December 27, 2024, at 2103 mountain standard time, a Cessna T210L, N505SW, was substantially damaged when it was involved in an accident near Gallup Municipal Airport (GUP), Gallup, New Mexico. The pilot and one passenger were not injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 personal flight. According to the pilot, earlier on the day of the accident, she purchased 56.6 gallons of fuel for the airplane. The pilot stated that the fuel gauges indicated both fuel tanks were full, but she did not visually verify the fuel level in the tanks. The pilot and passenger departed GUP and flew to Lake Havasu City Airport (HII), Lake Havasu City, Arizona, with an enroute stop at Cottonwood Airport (P52), Cottonwood, Arizona. The pilot stated these two flight legs totaled 3 flight hours as indicated by the airplane’s tachometer. While at HII, the pilot used the self-serve fuel pump to add about 10 gallons of 100LL fuel to each of the airplane’s two wing fuel tanks. The pilot used the airplane’s fuel gauges to determine the fuel quantity, stating that each gauge indicated 35 gallons of fuel, or 70 total gallons. The pilot did not visually verify the fuel level in the tanks. The pilot and passenger subsequently departed on the return flight to GUP about 1900. According to the pilot, the flight from HII to GUP took two hours. As the airplane entered the base turn to land on runway 24 at GUP, the pilot noted that the airplane was descending faster than expected and added engine power; however, the engine did not respond. The pilot verified the position of the engine controls and fuel selector and noted each fuel gauge appeared to be half-full. The pilot stated the airplane was unable to reach the runway and initiated a forced landing in a vacant lot about 1,800 ft west of runway 24. During the forced landing, the airplane impacted power lines and rough terrain, which resulted in substantial damage to the right wing and fuselage. Two days after the accident, the airplane was moved from the vacant lot to a parking lot at GUP. The pilot was present when the airplane was moved and stated that an unknown quantity of fuel leaked from the airplane’s belly. According to the airport manager, only trace amounts of fuel were observed within the airplane’s fuel system. About two months after the accident, the airplane was transported from GUP to a storage facility. Personnel who disassembled the airplane drained fuel from each of the wing tanks; they estimated about 3 to 4 ounces of fuel was recovered from the left wing fuel tank, and about 16 ounces of fuel was recovered from the right wing fuel tank. The fuel selector was found set to the left fuel tank, and impact damage prevented it from being turned by hand. Examination of the airplane and engine revealed no evidence of preimpact malfunctions or anomalies. The left fuel collector tank was impact-damaged and displayed a small crack on the upper surface, less than .125 inch long, that was ringed with blue fuel stains. No other leaks or breaches were found in the airplane’s fuel system. The engine was subsequently test run, during which it operated smoothly and continuously through various power settings. The wings were each raised using a forklift and moved adjacent to their respective wing roots. The wiring for the fuel quantity indicators was reconnected, and the wings were situated to simulate dihedral. Fuel was added to each wing fuel tank in increments, and the gauge was read at each increment. The following observations were made: The airplane’s fuel storage system consisted of two vented integral fuel tanks (one in each wing) and two fuel reservoir (collector) tanks. Fuel flowed by gravity from the two integral tanks to two reservoir tanks, and from the reservoir tanks to a three-position selector valve labeled LEFT ON, RIGHT ON, and OFF. Fuel cannot be used from both tanks simultaneously. Of the airplane’s 90-gallon fuel capacity, one gallon (or .5 gallon per tank) is considered unusable, and cannot be safely used in flight. Additionally, the fuel consumption rate ranges from 6 to 20 gallons per hour in normal operating conditions, with 20 to 28 gallons per hour during takeoff and climb.