Aerodrome beacon
An aerodrome beacon or rotating beacon or aeronautical beacon is a beacon installed at an airport or aerodrome to indicate its location to aircraft pilots at night. An aerodrome beacon is mounted on top of a towering structure, often a control tower, above other buildings of the airport. It produces flashes similar to that of a lighthouse. Airport and heliport beacons are designed in such a way to make them most effective from one to ten degrees above the horizon; however, they can be seen well above and below this peak spread. The beacon may be an omnidirectional flashing xenon strobe, or it may be an aerobeacon rotating at a constant speed which produces the visual effect of flashes at regular intervals. Flashes may be of one, two, or three alternating colors (described below). In the United States In the United States, the Federal Aviation Administration (FAA) has established the following rules for airport beacons: Flashing rates 24 to 30 per minute for beacons marking airports, landmarks, and points on Federal airways 30 to 45 per minute for beacons marking heliports Color combinations White and Green — Lighted land airport Green alone* — Lighted land airport White and Yellow —