Helicopter Hard Landing After Fueling with Aviation Gasoline (N3961H)

Incident Overview During an air tour flight at an air show, a pilot fueled a turbine-powered helicopter. The aircraft normally uses Jet A fuel, but the facility where the pilot was located only had 100LL aviation gasoline available. The pilot added 15 gallons of 100LL aviation gasoline to the less than 10 gallons of Jet A fuel already on board. ## Flight and Emergency Twenty-two minutes into the flight, while en route to a facility where Jet A fuel was available, the helicopter experienced a partial power loss. The pilot performed an autorotation, which terminated in a hard landing. ## Contributing Factors According to the operating manual, Jet A fuel and aviation gasoline may be mixed. However, when this is done, the fuel boost pump must be used while operating. The pilot did not have the fuel boost pump on.