Beech C90 N717X accident near Lecanto, Florida

Probable cause

The pilot's failure to turn on the fuel transfer pumps in accordance with the published checklists, which resulted in a dual loss of engine power due to fuel starvation.

NTSB analysis

The commercial pilot reported that, before a short, cross-country, personal flight, he purchased 40 gallons of fuel; 20 gallons of fuel were added to each wing tank. The pilot estimated that, at the time of departure, the airplane had a total fuel load of about 130 gallons with 65 gallons in each wing tank. About 10 minutes after departure, the left engine's power surged. The pilot attempted to divert to a nearby airport, but the left engine lost all power during the approach, followed by the right engine losing all power. The pilot was not sure if the airplane could glide to the runway, so he chose to perform a forced landing to a field. During the landing roll, the right wing impacted a tree and was substantially damaged.

The airplane was equipped with six fuel tanks; two interconnected tanks in each wing and one tank in each engine's nacelle. On each side of the airplane, fuel flowed from the respective wing tanks to the nacelle tank and then to the engine. Fuel would gravity feed from the wing tanks to the nacelle tanks; however, gravity feed did not work once each wing tank was depleted to about 28 gallons or below. At that point, the fuel transfer pumps (one for each wing/nacelle) must be on to keep the fuel moving to the nacelle tanks and ultimately the engines.

Examination of the wreckage revealed that the fuel transfer pumps were in the "off" position. No fuel was found in the nacelle tanks, and about 30 gallons of fuel were found in each wing tank. When the battery and fuel transfer pumps were turned on, fuel began to flow from each wing tank to its respective nacelle tank. Turning on the fuel transfer pumps is an After Starting and Taxi checklist item; therefore, it is unlikely that the pilot followed the checklist and that he forgot to turn the fuel transfer pumps on, which resulted in fuel starvation to both engines and their subsequent loss of power.

Text from the NTSB. Open the NTSB docket for ERA18TA203 for the full record.