Incident Overview
On August 2, 2015, about 1910 mountain daylight time, a Piper PA-28-181 (registration N7963C) made an off-airport landing following a loss of engine power near American Falls, Idaho. The airplane was operated by Aspen Flying Club under 14 Code of Federal Regulations Part 91. The private pilot and two passengers were not injured. The airplane sustained substantial damage to the left wing, the main landing gear separated, and the nose gear was crushed upward.
Flight Details
The cross-country personal flight departed Lincoln, California (KLHM) at 1430 MDT, with a planned destination of Idaho Falls, Idaho. Visual meteorological conditions prevailed, and no flight plan had been filed. During the multi-leg trip, the pilot reported trouble starting the engine in Santa Monica, California, where maintenance personnel cleaned fouled spark plugs.
On the day of the accident, the pilot departed San Francisco, California, and stopped for fuel in Lincoln. The pilot stated that with full tanks the airplane could fly 5-5.5 hours, and he intended the next fuel stop to be 4.5 hours later at Idaho Falls. He was receiving visual flight rules flight following from Salt Lake City Air Route Traffic Control Center.
Sequence of Events
Four hours into the flight, the pilot determined that the groundspeed was less than planned. The left fuel tank indicated 5 gallons, and the right indicated more than 5 gallons, so the pilot estimated sufficient fuel for 1 more hour of flight. The airplane was over Burley, Idaho, airport, but the pilot was unfamiliar with it and decided to continue to Pocatello, Idaho, expecting to arrive with fuel for an additional 30-45 minutes.
About 10 miles and 3-5 minutes from Pocatello, the right fuel tank indicated empty and the left tank indicated 2-5 gallons with the indicator shaking. This was 4 hours 40 minutes into the flight, and then the engine stopped. A nearby road had power lines, so the pilot elected to land in a field. After landing, the pilot noted that the left fuel gauge still indicated 5 gallons.
Examination Findings
A Federal Aviation Administration inspector examined the wreckage at a recovery facility in Boise, Idaho. Recovery personnel reported that the fuel tanks were not breached, and they drained no fuel from either wing tank, and a few ounces from the gascolator. The inspector obtained thumb compression on all cylinders. All spark plugs were grey except a slight oil film on the bottom plugs for cylinders two and four. There was no abnormal wear, fouling, or burn patterns on the spark plug electrodes. The gascolator screen and bowl showed no evidence of corrosion or contaminants. Upon removal of the hose and end clamp to the electric fuel pump, about 1 teaspoon of fuel flowed from the hose. About 2 ounces of clean, light blue fuel drained from the carburetor fuel bowl drain plug. The carburetor internal finger screen contained light contamination. No anomalies were observed that would have precluded normal operation of the engine.
Pilot Information
The 23-year-old pilot had 92 hours total flight experience, with 50 hours as pilot-in-command and 26 hours in the accident aircraft type.