On June 8, 2000, at 1720 central daylight time, a Piper PA-28-235 airplane, N9407W, was substantially damaged when it impacted terrain during a forced landing following a loss of engine power near Sugar Land, Texas. The airplane was registered to a private individual and operated by the pilot. The instrument rated private pilot, who was the sole occupant, was not injured. Visual meteorological conditions prevailed and a flight plan was not filed for the 14 Code of Federal Regulations Part 91 personal flight. The local flight originated from the Sugar Land Municipal Airport approximately 10 minutes prior to the accident, and was destined for the West Houston Airport, Houston, Texas. During a telephone interview conducted by the NTSB investigator-in-charge, the pilot reported that he departed the Sugar Land Municipal Airport and the airplane was climbing through 1,500 feet, when the engine "spooled down." The pilot stated that he pushed the engine controls forward and turned on the auxiliary fuel pump; however, he did not detect a change in engine power. The pilot elected to make a forced landing in a field approximately 2 miles from the departure airport. During the landing roll, the left main landing gear impacted an ant hill resulting in the separation of the left main landing gear. The FAA inspector, who responded to the accident site, stated that he found the fuel selector in the off position. The inspector stated that he found the left auxiliary fuel tank "completely empty," the left and right main fuel tanks full, and the right auxiliary fuel tank containing 3.5 gallons of fuel. The airplane was taken to an aircraft maintenance facility in Houston. The FAA inspector stated that the mechanics test ran the engine on the airplane. The mechanics reported that the engine would not start and run with the left auxiliary fuel tank selected; however, the engine started and ran approximately 15 minutes on each of the remaining fuel tanks. The mechanics also reported that the left wing spar was structurally damaged. The FAA inspector stated that the pilot indicated that he thought he had taken off with the left main fuel tank selected. The pilot reported that he had a total of 9 flight hours in the accident airplane and 767 total flight hours.