Why Do Electrical Towers Have Different Colored Blinking Lights?

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The recent proliferation of radio and TV stations, not to mention cell phone towers, has made tall metal Erector Set-type configurations a common sight along the American landscape. And one thing these structures have in common is the blinking Aviation Warning Light situated at the very top. Whether it’s a skyscraper, an electrical tower, or a radio antenna, once a structure tops 200 feet, the FAA gets involved.

There are very strict guidelines as to the candle power of the beacon. Either red or white light is acceptable, but red is more commonly used in areas where aircraft regularly fly at night. The lights must be connected to an appropriate control device (photo cell, timer, etc.) so that the brightness is adjusted appropriately and automatically in relation to the sky illumination. In the event of a power outage or burned-out bulb, the local FAA office must be notified within 30 minutes, and repairs must be made promptly. The warning lights must be observed and logged daily, unless they are equipped with an automatic alarm system that detects any failure.