EVALUATION OF CENTERLINE-LIGHTING INDICATIONS FOR RUNWAY-DISTANCE REMAINING AND TAXIWAY EXITS

Tests were conducted in the FAA Fog Chamber to determine the effectiveness of colored centerline lights for indicating runway-distance remaining and for marking high-speed taxiway exits (large-radius turnoffs) under daytime and nighttime visibility conditions down to 700 ft of visual range. The tests consisted of observations by pilots of various lighting patterns under simulated rollout conditions. The results of the tests indicate that red centerline lights can be effectively used for indicating runway-distance remaining, either in combination with white lights or alone if the intensity of the red lights is high enough to provide adequate guidance under reduced visibility. The test results also indicate that under conditions of 700-ft visual range, adequate identification and guidance for large-radius taxiway turnoffs can be provided by steady-burning, green lights along the taxiway centerlines, with a pattern having an equivalent intensity at least that of 1000-cp lights at 12.5-ft spacing in daytime and 500 cp at 12.5 ft at night. Steady-burning taxiway lights were preferred by the pilots over flashing lights by a very wide margin. Taxiway centerline lights having a much wider beam than that specified by the FAA were visible from a point on the runway centerline farther beyond the beginning of the taxiway turnoff than were the specified narrower-beam lights.