What does a complete taxiway lighting system look like?
No single light does the whole job. Blue edge lights define the pavement, green centreline lights give the path, exit lights and stop bars manage the way on and off the runway, and one control system ties the circuits together.
A taxiway lighting system is a set of different lights, each with its own colour, position and job, that together let a pilot find the pavement, follow a route and know where to stop. The pieces covered one by one in this section only make sense as a whole: what is lit, in which colour, and what is switched off at the same moment decides what the pilot sees.
1Define the pavement
Blue taxiway edge lights show the outline of the taxiway, with fixtures placed closer together on curves and at junctions so the shape stays readable. They are omnidirectional, so they can be seen from any approach.
2Guide the path
Green centreline lights run along the taxiway centreline and follow the curve into exits and junctions. On a runway-exit taxiway they alternate green and yellow near the runway and change to all green once an aircraft is clear of the protected area. Yellow tells the pilot the aircraft may still be inside it.
3Control entry and crossing
A red stop bar across the taxiway at a runway holding position means stop. It is switched off to clear an aircraft, and the centreline lights beyond it are lit instead. Yellow intermediate holding-position lights mark a stopping point short of another taxiway, and yellow runway guard lights warn that the taxiway is about to enter an active runway.
4One system behind the lights
Behind the fixtures, each light type is on its own series circuit fed by a constant current regulator. The airfield lighting control and monitoring system switches and dims those circuits, lights only the sections a route needs, interlocks stop bars with the centreline lights beyond them, and reports faults back to the operator.
| Light | Colour | Job |
|---|---|---|
| Taxiway edge lights | Blue | Show the pavement edge; omnidirectional |
| Taxiway centreline lights | Green | Guide aircraft along the taxiway centreline |
| Exit taxiway centreline lights | Alternating green and yellow, then green | Show the stretch of exit still within the protected area |
| Stop bar | Red | Stop at a runway holding position |
| Intermediate holding-position lights | Yellow | Mark a stopping point short of another taxiway |
| Runway guard lights | Yellow | Warn of an active runway ahead at a holding position |
| Signs | Yellow on black, black on yellow, white on red | Name, direct and mark mandatory stops |
Frequently Asked Questions
Q1What makes up a complete taxiway lighting system?
Blue edge lights, green centreline lights, alternating green and yellow exit lights, red stop bars, yellow holding-position lights and runway guard lights, plus the signs, the series circuits that feed them and the control system that switches them.
Q2Why do taxiway lights use different colours?
Colour tells the pilot what the light is for. Blue marks the pavement edge, green marks the centreline, red means stop, and yellow marks a holding position or the part of an exit taxiway that is still close to the runway.
Q3Does every taxiway need all of these lights?
No. Many taxiways use edge lights, centreline lights or both, depending on traffic, visibility conditions and the design standard in use. Stop bars, guard lights and holding-position lights are provided at the points where the standard or the aerodrome's operations call for them.
Q4How is the whole system controlled?
Each light type sits on its own series circuit fed by a constant current regulator in the vault. The airfield lighting control and monitoring system switches and dims the circuits, lights centreline sections for a cleared route, and interlocks stop bars with the centreline lights beyond them.
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