in an in - flight refueling system of an aircraft having a recess therein containing a slipway leading to a fuel inlet port , an improvement is provided in the form of a guideway having a ) a pair of lead - in lines on the surface of the aircraft which taper and converge towards the slipway and port and b ) a plurality of dashes or bars on the surface , spaced longitudinally between the lead - in lines , a desired distance apart , to provide visual cues in aiding an operator in guiding a fuel boom and nozzle from a refueling aircraft to the slipway and port of a fuel receiving aircraft , to provide a visually more salient means to achieve a quick and effective refueling hook - up while avoiding or minimizing nozzle strikes that can damage the aircraft , the boom or its nozzle .