Development of a Visual Aid to Indicate Temporary Runway Closure
Conclusions
From the results of this effort, it is concluded that the performance standards for a temporarily-closed-runway visual aid should be as follows:
1. The device should be a lighted signal in the shape of the letter "X".
2. The device should be capable of being acquired at a range of at least 5 nautical miles both day and night.
3. The signal should be recognizable as a letter "X" from at least 1-1/2 nautical miles both day and night.
4. The signal should provide horizontal coverage to at least 15 degrees on each side of runway centerline , and provide vertical coverage from 0 degrees to 10 degrees above horizontal, both day and night, at a range of 1-1/2 nautical miles.
5. The signal should pulse at a rate of three seconds "onon and one second "Off".