Incident Overview
According to the helicopter pilot's report, after completing an agricultural flight, the helicopter landed on a platform mounted on top of a truck for refueling. The ground crew connected both a fuel hose and a chemical hose to the helicopter. At the time of hose connection, the pilot was taking notes with his attention focused inside the cockpit. The pilot reported that he did not anticipate the chemical hose being attached to the helicopter.
Sequence of Events
Once the helicopter had received the required amount of fuel, the pilot used hand and arm signals to indicate to the ground crew that additional fuel would be needed after the next flight. The driver then removed the fuel hose from the helicopter and stepped back, making eye contact with the pilot. The pilot stated that the ground crew subsequently gave a "thumbs up" signal. The pilot interpreted this signal as confirmation that the helicopter was clear and safe for departure. In response, the pilot returned the "thumbs up" signal and advanced the throttle.
As the helicopter began to ascend, the pilot noticed the ground crew motioning that the helicopter was still connected to the chemical hose. Observing that the chemical hose remained attached, the pilot applied aft cyclic control. During the resulting maneuver, the tail rotor struck the truck, followed by the main rotor also striking the truck.
Pilot's Assessment
In the NTSB Pilot Aircraft Accident Report, the pilot noted that the accident could have been prevented had he visually confirmed with his own eyes that all possible connecting hoses were indeed disconnected and that the departure could be safely executed. The pilot also reported that there were no preaccident mechanical malfunctions or failures with the helicopter that would have precluded normal operation.