On November 14, 1994, at 1015 mountain standard time, a Piper PA- 23-160, N3323P, collided with the terrain five miles north of Casper, Wyoming, after both engines experienced a loss of power in cruise flight. Visual meteorological conditions prevailed at the time and no flight plan was filed. The airplane was substantially damaged and the commercial pilot, the sole occupant, was not injured. The flight had departed from Fargo, North Dakota, on November 14, 1994, at 0700 central standard time, for the personal flight. The pilot reported that the fuel tanks were topped off on November 11, 1994. On the day of the accident the pilot stated that he visually checked the fuel tanks during the pre-flight inspection and noted that the tanks were full. Total fuel capacity is 108 gallons. The pilot reported that the planned flight time to Casper was to be four hours and twenty minutes. The endurance for the airplane was planned at five hours. The pilot had planned a fueling stop at Casper, then to continue on to Ogden, Utah. Approximately 15 miles north of Casper, the pilot stated that the left fuel warning light illuminated. The pilot switched to the other fuel tank and stated that the right fuel warning light illuminated and the engine sputtered. The pilot then switched fuel tanks again and the right engine resumed full power. The left engine then lost power, followed by the right engine. The pilot notified Casper tower that he would not make it to the runway and initiated a forced landing to an open area. During the gear up landing, the airplane collided with the rough terrain. During the recovery of the airplane, a Federal Aviation Administration Inspector from the Casper, Wyoming, Flight Standards Field Office, reported only a small amount of fuel remained in the fuel tanks. The airplane is not equipped with a fuel flow meter, and the pilot stated that the fuel gauges are not accurate below the one- half mark.