An aerodrome beacon, airport beacon, 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
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In the United States, the Federal Aviation Administration (FAA) has established the following rules for airport beacons:[1]
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 — Lighted water airport
- Yellow alone* — Lighted water airport
- Green, Yellow, and White — Lighted heliport
- White, White, Green** — Military Airport
- White, Green, Amber — Hospital and/or Emergency Services Heliport
- *Green alone or yellow alone is used only in connection with a white-and-green or white-and-yellow beacon display, respectively.
- **Military airport beacons flash alternately white and green, but are differentiated from civil beacons by two quick white flashes between the green flashes.
In Class B, C, D, and E surface areas, operation of the airport beacon between sunrise and sunset often indicates that the ground visibility is less than 3 miles and/or the ceiling is less than 1,000 feet. This is true particularly at locations where beacon controls are available to air traffic control personnel;[2] however there is no regulation requiring daytime operation.[1]
At some locations with operating control towers, ATC personnel turn the beacon on or off with controls in the tower. At many airports the airport beacon is turned on by a photoelectric cell or time clocks, and ATC personnel cannot control them.[1]
In Canada
editIn Canada, the regulations are different. Lighted aerodromes are equipped with white single flash beacons operating at a frequency of 20 to 30 flashes per minute. Heliports with beacons exhibit the morse letter H (4 short flashes) at a rate of 3 to 4 groups per minute.[3]
See also
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- Index of aviation articles
- Instrument landing system, for the radio-frequency beacons used to locate aircraft.
Notes
edit- ^ a b c AJV-8, Air Traffic Procedures (2019-08-15). "Aeronautical Information Manual". Federal Aviation Administration. 2–1–10. Retrieved 2019-08-31.
{{cite web}}: CS1 maint: numeric names: authors list (link) - ^ AJV-8, Air Traffic Procedures (2019-08-15). "FAA JO 7110.65Y – Air Traffic Control". Federal Aviation Administration. 3–4–18. Retrieved 2019-08-31.
{{cite web}}: CS1 maint: numeric names: authors list (link) - ^ Transport Canada (23 October 2008). "TC AGA". Archived from the original on 17 June 2008.