How does a beacon flash with nothing turning?
White and green LED modules ring the beacon body, and a controller flashes the white group and then the green group, so there is no motor, gearbox or turning lens.
An LED beacon makes its flash electronically. LED modules sit all the way round the beacon body, white and coloured ones side by side, and a driver and controller flash the white group, then the coloured group, in turn. The pilot sees white and coloured flashes alternate, as with a rotating beacon, but nothing turns, so there is no motor, gearbox, bearings or lens carrier to wear out.
The flash rate is set by the controller and not by a motor speed. The colour usually comes from the LED itself, so there is normally no filter to fade. LEDs reach full output at once, draw less power and last longer than a lamp, and the controller can report status to the ALCMS. The beacon still has to meet the same colour, flash-rate and intensity rules as any aerodrome beacon, so check that the model is certified to the standard the aerodrome is designed to. Typical faults are in the driver, the controller or individual LED modules.
Frequently Asked Questions
Q1What is an LED beacon?
A beacon that uses LED modules as its light source and makes the flash pattern electronically. A controller switches the LEDs on and off, so there is no motor, gearbox or turning lens.
Q2How does an LED beacon make its flashes without turning?
LED modules sit all the way round the beacon body, white ones and coloured ones. The controller flashes the white group and then the coloured group at the required rate, and the pilot sees white and coloured flashes alternate, just as with a rotating beacon.
Q3What are the advantages over a rotating beacon?
No moving parts to wear out, so less maintenance. The flash rate is set by the controller and not by motor speed. LEDs reach full output at once, use less power and last longer than a lamp. The colour usually comes from the LED, so there is normally no filter to fade.
Q4Do LED beacons have to meet the same rules?
Yes. An aerodrome beacon still has to meet the colour, flash-rate and intensity requirements that apply, whatever technology makes the light. Check that the model is certified to the standard the aerodrome is designed to.
Q5What fails in an LED beacon?
Typically the driver or controller, or individual LED modules. A good design keeps the beacon working when one module fails and raises an alarm so the module can be replaced.
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