On August 10, 2023, about 0640 Pacific daylight time, a Remos GX, N72GX, was substantially damaged when it was involved in an accident in Henderson, Nevada. The flight instructor and student pilot were not injured. The airplane was operated as a Title 14 Code of Federal Regulations Part 91 instructional flight. The accident flight was an introductory lesson for the student. The flight instructor stated that, before departure, he thought that the airplane had 7.5 gallons of fuel onboard, which would have been equivalent to about 1 hour and 30 minutes of flight time. He departed to the south and began to demonstrate basic maneuvers. After completing around 3 turns, which occurred about 15 minutes into the flight, the engine sputtered. The flight instructor turned toward a dry lakebed and began troubleshooting. The engine continued to sputter and was losing power. The engine instruments showed nothing unusual, but he noted that the fuel gauge indicated that the tank was empty. The engine lost complete power and the flight instructor glided toward a dirt road. The airplane touched down on the road and the airplane nosed over after encountering a ditch. After egressing the airplane, the flight instructor verified that there was no fuel in the visual fuel tube, indicating there was no fuel in the system. An examination was performed by a mechanic under the auspice of a Federal Aviation Administration inspector. The mechanic removed the seats, and panels in the cabin were opened to access the fuel tank and fuel lines. No defects or evidence of leaks were found. The fuel cap was secure, and the fuel filler cap O-ring was present and in good condition. No evidence of a leak was found on the fuselage or tail behind the fuel filler cap. The mechanic sumped the fuel tank, revealing an operable sump valve and no signs of leakage or damage. There was a small amount of "unusable" fuel in the tank. A visual inspection of the fuselage fuel lines, and the fuel shutoff valve revealed no defects or evidence of leaks. Upon inspecting fuel lines forward of the firewall to carburetors, no anomalies were found. The mechanic removed the carburetor’s fuel bowls and they were empty. Removal of the lower spark plugs revealed they were light grey, consistent with a lean engine operation. The examination revealed no evidence of preimpact mechanical malfunction or failure that would have precluded normal operation.