What happened
On August 2, 2015, at approximately 1910 MDT, a PIPER PA 28-181, registration N796 and N7963C, performed an off-airport landing near American Falls, Idaho. The aircraft, operated by Aspen Flying Club, was on a multi-leg cross-country flight that had departed from Lincoln, California, with an intended destination of Idaho Falls, Idaho.
Four hours into the flight, the pilot observed that the groundspeed was lower than anticipated. At that time, the left fuel tank indicated 5 gallons and the right tank indicated more than 5 gallons. Although the aircraft was over the Burley, Idaho, airport, the pilot chose to continue toward Pocatello, Idaho, estimating there was enough fuel for an additional hour of flight.
Approximately 10 miles and 3 to 5 minutes from Pocatello, the right fuel tank indicator showed empty, while the left tank indicator showed between 2 and 5 gallons with a shaking needle. Shortly after, the engine stopped. To avoid power lines located near a nearby road, the pilot elected to land in a field. The landing resulted in the main landing gear separating, the nose gear being crushed upward, and substantial damage to the left wing. The pilot and two passengers were not injured.
The investigation
An FAA inspector examined the wreckage in Boise, Idaho. The investigation found that the fuel tanks were not breached and were empty, with only residual fuel found in engine components and approximately 2 ounces of clean fuel in the carburetor bowl drain. The gascolator screen and bowl showed no signs of contamination or corrosion. Examination of the spark plugs showed no abnormal wear, fouling, or burn patterns. The inspector found no mechanical anomalies that would have prevented the engine from operating normally.