Learn what runway lights mean, how edge, threshold and centreline systems work, and how pilots use them during landing, take-off and rollout.
In real-world aviation, runway lights identify the usable runway, its edges, threshold, centreline, touchdown zone and end. Pilots read their colours and patterns to confirm alignment, see where landing pavement begins, maintain directional control and judge runway remaining. Approach and glidepath lights support the approach but are separate systems.
What do the different runway light colours mean?
White generally defines the runway, green marks its landing threshold and red marks its end. The precise installation depends on the runway category and national standard, so not every runway has centreline, touchdown-zone or colour-coded distance-remaining lights.
| Lighting system | Normal appearance | Meaning to the pilot |
|---|---|---|
| Runway edge lights | Steady white along both edges | Define the runway's lateral limits. On many instrument runways, the final approximately 600 m (2,000 ft), or a shorter prescribed fraction, appears yellow to warn that the end is approaching. |
| Threshold lights | Green when viewed from the approach | Mark the beginning of pavement available for landing. At a displaced threshold, the green line is farther down the physical pavement. |
| Runway end lights | Red when viewed from the runway | Mark the end of usable runway. A bi-directional fitting can show green from the approach side and red from the opposite direction. |
| Runway centreline lights | White, followed by alternating red and white, then red | Provide alignment and runway-remaining information. A common pattern changes to alternating red and white for the final approximately 900 to 300 m (3,000 to 1,000 ft), then all red for the last 300 m (1,000 ft). |
| Touchdown-zone lights | Rows of white bars on each side of the centreline | Identify the normal touchdown region, usually extending from the threshold to approximately 900 m (3,000 ft) or the runway midpoint, whichever comes first. |
The yellow edge-light caution zone and red centreline lights do not mean the aircraft is off course or below the glidepath. They mean the runway end is getting close.
Which lights guide the approach rather than the runway?
Approach, threshold-identification and visual glidepath lights help pilots find and approach the runway, but they perform different jobs from runway lighting.
- Approach lighting systems are patterned arrays extending out from the threshold. They help pilots acquire the runway environment and transition from instrument references to visual alignment.
- Runway end identifier lights are synchronised flashing white lights on either side of the threshold. They make the landing threshold easier to locate among surrounding lights.
- PAPI, VASI and T-VASIS provide vertical-path guidance. With a four-light PAPI, two white and two red normally indicate the correct path; more white means high and more red means low.
A PAPI indication is meaningful near the extended runway centreline and does not replace the published approach or obstacle-clearance requirements. PAPI and an ILS glidepath can also differ slightly because they use different equipment positions and reference points.
How are runway lights different from taxiway lights?
The easiest night-time distinction is white runway edge lighting versus blue taxiway edges and green taxiway centreline lighting. Confusing a green taxiway centreline with a green runway threshold is a serious wrong-surface warning sign.
- Blue lights mark taxiway edges.
- Green in-pavement lights normally mark a taxiway centreline.
- Flashing yellow runway guard lights identify a runway holding position.
- Red stop-bar lights mean stop; if a clearance conflicts with an illuminated stop bar, the pilot should hold and clarify the instruction.
The red, green and white lamps fitted to an aeroplane have another purpose entirely; our explanation of how aircraft navigation-light colours identify direction covers that distinction.
How do pilots use runway lights during landing and take-off?
Pilots use runway lights as cross-checks throughout the operation, not as a substitute for charts, clearance or flight instruments.
- Brief the lighting: Before arrival or departure, check the aerodrome chart, notices, displaced thresholds, available approach system and reported outages. Lighting does not choose the runway; wind, traffic, length, surface and procedures are among the factors used to select a landing runway.
- Identify the correct runway: Match the runway number and approximate magnetic heading, then cross-check the threshold, edge-light pattern and instruments. A lit runway is not necessarily assigned, open or cleared for use.
- Control the approach: Use the approach-light array to acquire alignment and PAPI or VASI as a visual glidepath reference. Under instrument rules, continue only when the required visual references and applicable minima are satisfied.
- Cross the threshold correctly: The green threshold lights mark where landing pavement begins, not the aiming point. The aiming point and touchdown zone are farther along the runway.
- Maintain alignment: During flare, landing roll or take-off, use the centreline and edge lights to detect drift. Centreline colour changes, yellow edge lights and red end lights provide increasingly urgent runway-remaining cues.
Can pilots land using runway lights alone?
Runway lights can provide the main external references for a visual night landing, but they do not replace weather minima, runway clearance, performance calculations or an authorised instrument procedure. Seeing approach lights also does not automatically permit descent all the way to the runway; the required visual references depend on the jurisdiction and operation.
An unserviceable lighting component can raise approach minima or make an operation unavailable. Pilots therefore use published outage information and instructions rather than deciding that a runway is safe merely because some lights remain visible.
Can pilots turn runway lights on themselves?
At controlled aerodromes, the tower normally controls runway-light intensity. Some non-towered airports, especially in the United States, use pilot-controlled lighting activated by a series of microphone transmissions on a published radio frequency.
A common US arrangement uses seven transmissions within five seconds for high intensity, five for medium and three for low. This is not a worldwide rule, and some installations use different arrangements or no radio control at all. Pilots must check the published aerodrome information rather than sending microphone clicks speculatively.
Excessive intensity can create glare in rain, fog or a dark cockpit. Pilots may request a lower setting from ATC when conditions permit, while still retaining enough light to identify the runway and maintain alignment.
What runway-light mistakes cause trouble?
- Confusing red indications: Red PAPI lights indicate a low approach, while red runway centreline or end lights indicate little runway remains.
- Aiming at the threshold lights: Trying to touch down on the green lights reduces threshold-crossing height and increases undershoot risk.
- Following the brightest pavement: A well-lit taxiway, road or parallel runway can look more prominent than the assigned runway. Runway number, heading and instruments must agree.
- Assuming every runway has every system: The absence of centreline or touchdown-zone lights can be normal for that runway.
- Treating lights as proof of availability: Lighting can remain on at a closed, occupied or unsuitable runway. Clearance and published status still govern its use.
Why do runway lights look wrong in a flight simulator?
Flight simulators reproduce the same colour meanings, but individual airport scenery can omit lights, place them incorrectly or render their intensity poorly. If only one airport is affected, suspect its scenery data or conflicting add-ons; if every airport is affected, check night brightness, exposure, display calibration and lighting-related graphics settings.
Missing centreline lights are not always a piloting mistake. An airport-specific centreline-light correction for Indira Gandhi International illustrates how scenery can require a local fix. Pilot-controlled microphone activation is also not modelled consistently, so some simulators or add-on airports require their own lighting command.