LED versus halogen runway lights
Two ways to make the same light: a glowing filament or a chip. Same circuit, same photometric job, very different life, power, heat and failure behaviour.
A halogen fixture burns a tungsten filament and filters the white light to the colour required. An LED fixture creates light directly in LEDs, shaped by an optic and powered by a driver. Both have to meet the same photometric requirements, in the same colours and brightness steps, on the same constant-current series circuit.
LED wins on life, power and colour efficiency, so there are far fewer lamp changes. Halogen wins on simplicity, purchase price and the waste heat that helps clear snow from inset fixtures. The choice is rarely about the light alone. It also depends on circuit loading, climate, vision systems and how the airport maintains its lights.
Long life, low power, colour built in. Needs a managed heat path and a compatible driver.
Simple filament lamp behind a lens and filter. Proven and cheap, but it wears out and runs hot.
| Aspect | LED | Halogen |
|---|---|---|
| Light source | LED board, one or more LEDs | Tungsten filament in halogen gas |
| Life | Tens of thousands of hours, with slow output loss | Limited: typically about 1,000 to 2,000 hours at full current, much longer at low steps |
| Power | A fraction of a lamp’s draw | Higher, close to a pure resistive load |
| Colour | Made by the LED, no filter loss | White light through a glass filter, which absorbs most of the output for coloured lights |
| Heat | Little at the lens; must be carried away from the LEDs | Plenty, which helps keep inset lenses clear of snow and ice |
| Response | Immediate to brightness steps; suits flashing and sequenced lights | Filament has thermal inertia, so it warms and cools more slowly |
| Circuit load | Driver electronics; check load, power factor and the CCR’s minimum load | Simple load, well understood |
| Failure | Gradual output loss, or sudden driver failure | Sudden burn-out; lamp replaced in service |
| Vision systems | Little infrared; check compatibility with cameras and enhanced vision | Broad spectrum including infrared |
| Maintenance | Routine lamp change largely disappears; cleaning, seals and photometric checks remain | Regular lamp replacement plus cleaning and checks |
| Purchase cost | Higher up front | Lower up front, higher over its life |
Checks when replacing halogen with LED
Circuit load
Re-calculate the series circuit load and power factor. A lighter load can change CCR loading and regulation, and may fall below the CCR’s minimum load.
Mixed technologies
Mixing LED and halogen fixtures within one lighting element can give uneven intensity and colour, and FAA AC 150/5340-30 (para 1.4) does not allow it: LED fixtures must not be interspersed with incandescent fixtures of the same type, and a failed halogen fixture must not be replaced by an LED one. Convert a whole lighting system at once, and check the rule that applies at your aerodrome.
Brightness steps
Confirm the fixtures follow every step of the CCR, with correct output at each and a steady light, with no flicker or stroboscopic effect, on the CCR type in use.
Photometrics
Check the new fixture meets the required intensity, colour and beam pattern for its position.
Snow and ice
Inset lights lose the lamp’s waste heat. Check heating options and the local snow-clearing method.
Cameras and vision systems
Confirm that aircraft and ground cameras and enhanced vision systems still see the lights.
Spares and training
Plan for driver and module spares, and change the maintenance routine from lamp changes to cleaning and photometric checks.
Runway Lighting LED Conversion
Before converting runway lights from halogen to LED, check the following:
- Circuit load. Re-calculate the series circuit load and power factor; a lighter load can change CCR loading and regulation, and may fall below the CCR’s minimum load.
- Mixed technologies. Mixing LED and halogen fixtures within one lighting element can give uneven intensity and colour, and FAA AC 150/5340-30 (para 1.4) does not allow it: LED fixtures must not be interspersed with incandescent fixtures of the same type, and a failed halogen fixture must not be replaced by an LED one. Convert a whole lighting system at once and check the rule that applies at your aerodrome.
- Brightness steps. Confirm the fixtures follow every step of the CCR, with correct output at each and a steady light, with no flicker or stroboscopic effect, on the CCR type in use.
- Photometrics. Check the new fixture meets the required intensity, colour and beam pattern for its position.
- Snow and ice. Inset lights lose the lamp’s waste heat, so check heating options and the local snow-clearing method.
- Cameras and vision systems. Confirm that aircraft and ground cameras and enhanced vision systems still see the lights.
- Spares and training. Plan for driver and module spares, and change the maintenance routine from lamp changes to cleaning and photometric checks.
Frequently Asked Questions
Q1What is the main difference between an LED and a halogen runway light?
A halogen fixture makes light by heating a tungsten filament in halogen gas, then uses a reflector, lens and colour filter to form the beam. An LED fixture makes light in LEDs on a board, shapes it with an optic and runs from a driver. The result is a very different life, power draw, heat output and failure pattern.
Q2Which lasts longer, LED or halogen?
LED. A halogen lamp has a limited life and is replaced in service, while an LED fixture is typically rated for tens of thousands of hours. LEDs still lose output slowly with age and their drivers can fail, so the rated life depends on the product and operating conditions. Check the manufacturer’s data.
Q3Do LED runway lights use less power than halogen?
Yes, typically a fraction of the power for the same photometric result, which reduces the load on the series circuit and the constant current regulator. The saving depends on the fixture type and on the brightness step in use.
Q4Why do some inset lights melt snow better with halogen?
A halogen lamp gives off a lot of waste heat, and in an inset fixture that heat helps keep the lens clear of snow and ice. An LED gives off far less heat at the lens, so some LED inset fixtures include heating or are used with other snow-clearing methods. Confirm behaviour for the climate in question.
Q5Can I replace a halogen lamp with an LED on the same series circuit?
LED fixtures are designed to run from the same constant-current series circuit and isolation transformer. Convert the whole lighting system rather than single fixtures, because FAA AC 150/5340-30 (para 1.4) does not allow LED and halogen fixtures of the same type to be mixed. Before changing, confirm the circuit load and power factor, the CCR compatibility, the brightness-step response, photometric compliance and any camera or vision-system compatibility. Do this with the manufacturer and the applicable standard.
Q6Is an LED fixture really maintenance-free?
No. There is no filament to burn out, but seals, lenses, connectors, drivers and the heat path still need inspection, cleaning and testing, and photometric checks remain part of maintenance. Only the routine lamp change largely goes away.
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