Geodata International

Rockwell Grand Commander 680

The aircraft crashed while doing magnetometer surveys at low altitude. The right engine had lost power then regained it for a short period and lost it again. A videotape in the aircraft recorded the pilot saying, 'I changed that # just in time.' the aircraft yawed and the propeller slowed at the same time. The fuel selector valves were found on the center tanks. The boost pump switches were found in the off position. When changing from outboard to center tanks the boost pumps must be on or fuel starvation will occur. As the aircraft slowed the tape revealed that the copilot called out 'down to 90'. 90 mph is VMC. The aircraft stalled, shortly after the asymmetrical thrust rolled the aircraft to the right and into the ground. Both occupants were killed.