On November 1, 1999, at 1630 central standard time, a Cessna 172B airplane, N7833X, was substantially damaged when it impacted trees and terrain during a forced landing near Beaumont, Texas. The certified flight instructor and student pilot were not injured. The airplane was registered to an operated by a private individual. Visual meteorological conditions prevailed for the 14 Code of Federal Regulations Part 91 instructional flight and a flight plan was not filed. The local flight originated from the Beaumont Municipal Airport, Beaumont, Texas, at 1500. According to the flight instructor, he visually confirmed that each wing fuel tank was 1/2 full during the preflight inspection. He estimated that he had approximately 2 hours of flying time based on the quantity of fuel in the tanks. The airplane departed and flew approximately one hour before returning to the airport. The student was executing touch-and-go landings on runway 31, and during the fourth takeoff/climb, as the airplane turned cross-wind, the engine began to "sputter." The flight instructor assumed control of the airplane and turned the airplane toward runway 13. The airplane had overflown 1/2 the length of the 3,601-foot runway when the instructor advanced the throttle to see if the engine would respond. The engine responded, and the instructor initiated a climb, intending to initiate another approach. The instructor turned the airplane back toward runway 31, and simultaneously, the engine "sputtered" and lost total power. The instructor executed a forced landing to a field. While on short final to the field, the airplane's wings struck trees, and the airplane contacted the ground. The airplane came to rest upright, 0.5 miles from the approach end of runway 31. The instructor stated that he visually checked the fuel tanks after the accident, and there "appeared to be little fuel in both tanks." The FAA inspector, who examined the airplane, reported that both wing spars were structurally damaged. He added that the fuel tanks contained "residual fuel only."