Cessna 172L accident near Mcneil Island, Washington, March 26, 2016

The NTSB's narrative final · quoted from the NTSB record

The student pilot departed on the solo cross-country flight with about 4 hours of fuel onboard. About 2 hours into the flight, he noticed that the left tank fuel gauge was indicating almost empty. He was not concerned about the indication, stating that he had been trained not to rely on the accuracy of the fuel gauges. However, after landing at one of the intermediate airports along his route of flight, he did not visually check the fuel levels at the tank filler necks. About 45 minutes after takeoff from that airport, the engine experienced a partial loss of power. Concerned that performing troubleshooting steps could further exacerbate the situation, the student did not follow any emergency checklists. For the next 5 minutes, the engine continued to operate intermittently as the airplane gradually descended, then experienced a total loss of power. The student made a forced landing to a field, and the airplane nosed over during the landing roll. Following the accident, the fuel selector valve was found in the left tank position, and the left tank was about one-quarter full. Although enough fuel remained in the left tank to power the engine, it had most likely migrated from the right to left tank via the tank vent crossover line, as the airplane lay inverted for several days after the accident. The fuel capacity of the left tank was about equal to that which would have been used during the flight. Postaccident examination did not reveal any anomalies with the airframe or engine that would have precluded normal operation. The engine was tested while attached to the airframe and fuel supply system, and ran uneventfully at various power settings. Thus, the partial, then total, loss of power is consistent with a fuel starvation event. The student stated that he always operated the airplane with the fuel selector valve in the "both" position and that, on the day of the accident, he only checked it once during the preflight inspection before the first takeoff. If the student had verified the fuel selector position before takeoff on the accident leg, as required in the engine start and before takeoff checklists, or switched tanks when the engine began to run rough, the total loss of engine power would not have occurred.

The complete narrative as the NTSB published it. The NTSB's docket holds the report as a PDF and any photographs, statements and other documents from the investigation.