code beacons

code beacons

Aeronautical beacons that can be seen from all directions. They identify airports and landmarks and mark obstructions. Green-coded flashes, not exceeding 40 flashes or character elements per minute, identify land airports. Yellow-coded flashes, not exceeding 40 flashes per minute or constant flashes of 12 per minute, identify water airports. Red flashes, 12 to 40 flashes per minute, mark hazards.
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