On August 30, 2012, about 0948 mountain daylight time, a Cessna 210, N7321E, sustained substantial damage during a forced landing following a loss of engine power near Kemmerer, Wyoming. The airplane was registered to Zibby Flight Service LLC., Lewes, Delaware, and operated by the pilot under the provisions of Title 14 Code of Federal Regulations Part 91. The private pilot and his passenger were not injured. Visual meteorological conditions prevailed and no flight plan was filed for the personal flight. The cross-country flight originated from Williston, North Dakota, at 0700 central daylight time with an intended destination of Heber City, Utah.

The pilot reported that prior to the flight, he verified that both fuel tank fuel levels were full and reviewed the pilot operating handbook (POH) for fuel consumption. The pilot stated that at 10 psi indicated on the fuel flow gauge, the airplane should have been able to fly 700 miles with a sufficient visual flight rules (VFR) reserve, as his intended flight was about 654 miles in length.

The pilot further reported that he departed Williston, which has a reported field elevation of 1,982 feet mean sea level (msl), and climbed to 6,500 feet msl and remained at that altitude throughout North Dakota and Montana. As the flight crossed the Wyoming border, he began a cruise ascent to 12,500 feet msl, where he remained at until crossing the Big Horn mountain range. The pilot stated that he descended to 10,500 feet msl until crossing over Riverton, Wyoming, where he initiated a second ascent to 14,500 feet msl. Upon crossing the Wind River mountain range, he descended to 10,500 feet msl, when he noticed that the left and right fuel gauges indicated one-quarter tank fuel levels. The pilot initially diverted to Fort Bridger, Wyoming, however, he was unsure if the fuel gauges were indicating properly, and diverted to Kemmerer. The pilot further stated that while descending through 9,000 feet msl, the left fuel tank “gave out”; he then switched to the right fuel tank. As the flight approached Kemmerer, the engine lost power. Despite the pilot’s attempts, the engine would not restart and he initiated a forced landing to an open field. Subsequently, the airplane landed gear up and came to rest upright.

The passenger reported that during the flight, he had talked to the pilot about each instrument, and recalled that the pilot had the fuel pressure gauge set between 9 and 10.

Examination of the airplane by the pilot revealed that the fuselage was structurally damaged. The pilot and passenger also noted a blue streak originating from the right fuel cap. The airplane was recovered to a secure location for further examination.

Examination of the airframe revealed that both the left and right wings were separated from the fuselage by wreckage recovery personnel. Wreckage recovery personnel reported that they removed approximately four ounces of fuel from the right tank and about four gallons of fuel from the left fuel tank. The right wing was intact. Four of the five screws securing the fuel sending unit were finger tight. The fuel sending unit was removed and the seal appeared to be intact and undamaged. Dark staining was observed in the general area surrounding the fuel sending unit. The fuel cap was secure to the filler neck and undamaged. The fuel cap seal was intact. A purple color stain was observed about six inches aft of the fuel cap. The panel surrounding the fuel filler neck was removed allowing visual examination of the internal fuel tank. The fuel bladder tank was found mostly disconnected from all of the internal clips.

The left wing was intact. The fuel cap was secure to the filler neck and undamaged. The fuel cap seal was intact. The panel surrounding the fuel filler neck was removed allowing visual examination of the internal fuel tank. The fuel bladder tank was found disconnected from two of the internal clips.

No additional mechanical anomalies were noted.

Review of the Pilot Operating Handbook, Section VI, Operational Data, revealed cruise performance charts for various altitudes including 2,500 feet, 5,000 feet, 7,500 feet, 10,000 feet, and 15,000 feet msl provided hourly fuel burn, fuel pressure settings, and fuel endurance time. The chart labeled 5,000 feet showed that at 2,450 revolutions per minute (RPM), 24 inches of manifold pressure, fuel pressure of 10 psi, the fuel burn per hour was 14.8 gallons, 3.7 hours endurance, and a range of 700 statute miles in a no wind condition. There were no fuel burn calculations at 10 psi for the charts for 7,500, 10,000, and 15,000 feet altitudes; however, at 2,450 rpm they showed a fuel pressure and gallons per hour of 8.6 psi and 13.4 gallons/hour, 7.5 psi and 12.2 gallons/hour, and 5.5 psi and 9.7 gallons/hour respectively.

The airframe, engine, and propeller maintenance records were not located.