What precaution should be taken to eliminate the potential hazard of static electricity when refueling aircraft?

To mitigate the hazards of static electricity during refueling, establishing a proper grounding connection is crucial. Connecting a ground wire between the aircraft, the fuel truck, the fuel nozzle, and the ground ensures that any static electricity generated during the refueling process is dissipated safely. This connection provides a continuous path for electrical charges to flow away from the aircraft and refueling equipment, significantly reducing the risk of a static discharge that could ignite fuel vapors.

This method is especially important because static electricity can accumulate from various sources, including wind, movement, and the fuel transfer process itself. By ensuring all potential sources of static are grounded together, the likelihood of an electrical spark is minimized, making the process safer for both personnel and the aircraft.

Other methods, while they may contribute to safety, do not address the static electricity hazard as comprehensively as this method does. For instance, using a non-conductive fuel nozzle does not neutralize static charges, and simply switching off electrical equipment does not eliminate the possibility of static buildup. Each of these alternatives does not provide the complete safety mechanism that establishing a robust grounding system offers.