On June 13, 1998, at 1445 hours Pacific daylight time, a Scott Dragonfly, N824JC, an experimental aircraft, experienced a loss of engine power during cruise and made an emergency landing in a soft dirt field near Mecca, California. The airplane, operated under 14 CFR Part 91, sustained substantial damage. The private pilot was not injured. Visual meteorological conditions existed for the personal flight that originated from the Riverside, California, airport the day of the accident. The flight was scheduled to terminate at the Chandler, Arizona, airport, and no flight plan was filed. The pilot reported that on June 10, 1998, he received instruction in the accident aircraft. On June 12, 1998, he received further instruction and purchased the accident aircraft. The pilot stated that the following day he departed the Riverside airport following Interstate 10 to Chandler. He stated that while in a climb, approximately 25 miles east of Bermuda Dunes airport, he observed a lowering trend on the fuel gage for the header fuel tank. He leveled off at 6,400 feet to obtain a more stabilized reading from the fuel gage and noted that it was now reading below the green mark on the fuel gage. The pilot reported that at this point he turned the aircraft to a westerly heading to make a precautionary landing at Thermal airport, approximately 15 miles from his current position on Interstate 10. Approximately 6 miles from the airport the engine surged and quit. The pilot made an unsuccessful attempt to restart the engine and had to make an emergency landing in a plowed field. On the landing roll, the main gear dug into the soft dirt field and the aircraft came to rest inverted. The previous owner of the aircraft stated that on the day of the accident the aircraft was refueled out of a gas can, but he did not remember the amount of fuel. He stated that the aircraft carries approximately 16 gallons of fuel and the header tank has approximately 45 minutes of flight time. The previous owner stated that the transfer pump is supposed to be on at all times, and the fuel is transferred from the main tank to the header tank via a transfer pump. The header tank is supposed to remain full at all times through this procedure. A site gage is available and when the fuel drops below the green mark it indicates that the transfer pump is either not on or there is something wrong with it. When the transfer pump is off, a red caution light illuminates to let the pilot know that something is not working properly. The gravity fed bypass boost pump feeds the engine via the header tank. In an interview with a Federal Aviation Administration (FAA) inspector, the pilot reported that the fuel is transferred from the main tank to the header tank using a fuel pump that automatically engages when fuel in the header tank drops below a certain level. The pilot stated that he observed the fuel quantity tube in the header tank was low, and he decided to make a precautionary landing at Thermal airport. The pilot reported to the FAA that he and the seller of the aircraft inspected the fuel system after the accident. They found that a metal fuel line that is used to transfer the fuel from the main tank to the header tank was partially collapsed. According to the fuel company log sheets, two miscellaneous fuel sales were made on the day of the accident. One sale was for 10.8 gallons with no aircraft identifier, the other sale was for 5.2 gallons and was a cash sale in a gas can.