Static charges are formed by the friction of air passing over the surfaces of an aircraft in flight and by the flow of fuel through the hose and nozzle during refuelling. To guard against the possibility of static electricity igniting fuel fumes, a ground wire should be attached to the aircraft before the fuel cap is removed from the tank. Since the aircraft and refueler may have different static charges, bonding both components to each other is critical. By bonding both components to each other, the static differential charge is equalized. The refuelling nozzle should also be bonded to the aircraft before refuelling begins and should remain bonded throughout the refuelling process.