Piper PA31 N257SH accident near Fort Lauderdale, Florida

Probable cause

The pilot’s improper preflight fuel planning, which resulted in a total loss of engine power due to fuel exhaustion. Contributing to the accident was the pilot’s decision to continue to the destination following the loss of engine power to the first engine.

NTSB analysis

The pilot of the on-demand passenger flight about 10 to 15 miles from the destination when the twin-engine airplane’s left engine stopped producing power. The pilot opened the fuel cross-feed valve, switched on both fuel boost pumps, and restored power to the left engine. The pilot continued to the original destination rather than land at a closer airport because he believed that the right engine fuel gauge indicated adequate fuel to complete the flight. When the airplane was on a left base leg for landing, both engines lost total power.

The pilot made a forced landing on the grass between the runway and a taxiway, during which the airplane was substantially damaged. Postaccident examination of the airplane found that all of the fuel tanks were intact and empty of useable fuel. When the fuel system was tested, no leaks or other mechanical deficiencies were observed that would have precluded normal operation at the time of the accident.

The airplane’s inboard fuel tanks had most recently been topped off 3 days before the accident (the outboard tanks were kept empty for weight reasons), after which the pilot performed a round trip passenger flight. Before the accident flight, the pilot did not visually check the fuel level in fuel tanks as prescribed by the preflight checklist. He stated that the fuel gauges, which he did not believe were accurate, indicated that the inboard tanks were more than half full. Based on his previous experience with the airplane’s typical fuel consumption, he estimated that he had about 2 hours of fuel remaining onboard the airplane to complete the planned round-trip flight, plus a 30-minute reserve. Following the accident, the pilot stated that he was “stubbornly overconfident” that there was enough fuel to complete the flight and, based on his extensive experience flying the airplane, he calculated a fuel consumption of 40 gallons per hour (gph); but he admitted that he should have calculated a fuel consumption of 50 gph.

Based on the lack of fuel in the fuel tanks after the accident, as well as the confirmed postaccident integrity of the fuel system, it is likely that the pilot’s failure to verify the quantity of fuel onboard the airplane prior to the flight and his miscalculation of the airplane’s fuel consumption rate resulted in fuel exhaustion and the subsequent total loss of engine power. The accident likely also could have been avoided if the pilot landed immediately after the first loss of engine power rather than continuing to the originally planned destination.

Based on available medical and operational evidence, it is unlikely that the pilot’s diagnosed tremors or other medical conditions contributed to the accident. There was no evidence that the pilot’s use of medications or alcohol contributed to the accident; however, available evidence was limited and did not include postaccident toxicology results.

Text from the NTSB. Open the NTSB docket for ERA20LA331 for the full record.