Piper PA 28-181 N7963C accident near American Falls, Idaho

Probable cause

The low flight time pilot's inadequate in-flight fuel planning, which resulted in fuel exhaustion, a loss of engine power, and an off-airport landing in rough terrain.

NTSB analysis

The pilot reported that, before departing for the cross-country flight, the fuel tanks were full and that the airplane could fly about 5 to 5.5 hours with full tanks. He planned to stop at an airport and refuel 4.5 hours after departure. However, 4 hours into the flight, the pilot determined that the groundspeed was less than planned and that the airplane would not make it to the intended fueling destination. At this time, the left fuel tank quantity gauge indicated that the tank had 5 gallons, and the right fuel tank gauge indicated that the tank had more than 5 gallons, which he estimated was sufficient fuel for 1 more hour of flight, so he decided to continue to an alternate airport even though he was currently over another airport. The pilot reported that, about 10 miles from the alternate airport, the right fuel tank gauge indicated that the tank was empty and that the left fuel tank gauge indicated that the tank had between 2 and 5 gallons. Shortly thereafter, the engine lost power, and the pilot initiated a forced landing to a field, during which the airplane sustained substantial damage.

A postaccident examination of the airframe revealed that the fuel tanks were not breached and that they were empty; only residual quantities of fuel were observed in the engine ancillary components. The engine examination did not reveal any anomalies that would have precluded normal operation.

Text from the NTSB. Open the NTSB docket for WPR15LA237 for the full record.