What are runway end lights, and what do their colours mean?

Runway end lights are a transverse row of steady red lights marking the far end of the runway as seen by an aircraft on it. At the reciprocal approach, fittings at the same extremity may show steady green as threshold lights. Runway End Identifier Lights are different: they flash white beside the approach threshold.

In Aviation & Real-World Flying, viewing direction is the key detail. The fitting does not change colour as an aircraft passes; directional optics present the appropriate colour to traffic on the runway or approaching the threshold. From an off-axis viewpoint, those lights may look faint or disappear entirely.

What colour are runway end lights?

Runway end lights are steady red when viewed from the runway towards its far extremity.

The lights at the end of the runway are not a landing clearance, nor does green mean that the runway is safe to enter. Pilots must still follow ATC instructions, published procedures and runway occupancy checks. Our guide to runway-light colours and patterns explains how end lights fit with threshold, centreline and touchdown-zone lighting.

Why can one runway end light look red from one direction and green from the other?

The same runway extremity can serve as the end for one direction and the landing threshold for the reciprocal direction.

Consider Runway 09/27. On final for Runway 09, the near threshold row appears green and the far Runway 09 end appears red. Approaching from the opposite side for Runway 27, that former far extremity is now the near threshold and its approach-facing optics appear green.

This does not require a lamp to change colour. Combined threshold/end fittings contain directional optics: red faces aircraft travelling towards the runway end, while green faces aircraft approaching the reciprocal threshold.

A displaced threshold is an important exception to the simple same-row explanation. Its green threshold lights sit inboard from the pavement extremity, so they may not coincide with the reciprocal runway-end row.

What colour are Runway End Identifier Lights?

Runway End Identifier Lights, or REILs, flash white. They are normally installed as a synchronised pair, one on each side of the approach threshold.

Despite their name, REILs identify the approach end of the runway; they do not mark the far end encountered during the landing roll or take-off. Informal descriptions sometimes call them runway end identification lights, while some standards use the equivalent term runway threshold identification lights.

The distinction is easy to remember: a full steady red row means runway end, a full steady green row means threshold, and two flashing white lights identify the threshold. Our explanation of approach-light and threshold systems covers where REILs sit relative to the wider approach lighting.

What colour are runway edge lights?

Runway edge lights are normally steady white, with yellow lights used on many instrument runways as a caution that the far end is approaching.

The exact caution-zone length depends on the governing standard and airport installation. Under US conventions it is generally the last 2,000 feet or half the runway, whichever is less. ICAO-style installations use a comparable section of up to 600 metres or one-third of the runway, whichever is less. Yellow is also commonly described as amber.

At some displaced-threshold installations, edge lights bordering the pavement before the landing threshold show red towards an approaching aircraft. The green transverse threshold row, threshold markings and published runway layout remain the decisive cues.

Position separates these indications. Edge lights form two parallel lines along the sides; runway end lighting forms a transverse red row across the far end. Yellow edge lights warn that little runway remains, but pilots must not use lamp counts as a substitute for published distances.

Which airport lights are commonly mistaken for end-of-runway lights?

Pattern, location and whether a light is steady or flashing matter as much as its colour.

PAPI colours are especially easy to confuse with red runway lighting when viewed from a distance. Our practical guide to reading PAPI indications in a flight simulator explains the normal two-white, two-red on-slope indication.

Do red runway end lights always mark the end of the pavement?

No. Red runway end lights mark the operational runway boundary, but paved or prepared surface may continue beyond them.

A stopway, blast pad or other overrun area can lie beyond the red row. A stopway may be included in the accelerate-stop distance available for a rejected take-off, but it is not extra runway for a normal take-off or landing. A blast pad is not intended for normal aircraft movement.

A displaced threshold creates the opposite situation at the approach end: pavement exists before the green threshold, but touchdown from that direction must occur beyond it. Depending on the published layout, the preceding pavement may remain available for taxiing, take-off or operations in the reciprocal direction.

Runway end lights also do not mean that a runway is closed. Closure crosses, holding-position markings, signs and operational notices are separate cues; see our guide to runway signs and surface markings for those distinctions. Published LDA, TORA and other declared distances remain authoritative for performance planning.

Do all runways have runway end lighting?

No. Unlit runways and some small aerodromes have no runway end lights, while other systems operate only during specified hours or after pilot activation.

If no red end row is visible, do not assume that the pavement remains usable or that the runway is closed. Check the published lighting information and any ATC instruction. Weather, low intensity, terrain, viewing angle and a displaced threshold can all make a working installation difficult to recognise.

How should you identify runway end lights in a flight simulator?

Use the cockpit view on the runway centreline and look for the near-green, far-red relationship.

This method applies to Microsoft Flight Simulator 2020 and 2024, FSX, Prepar3D and X-Plane, although individual airport scenery can simplify or misplace the lighting.

1. Confirm the runway direction. Match the runway number in the clearance or flight plan to the end being approached. Looking at the reciprocal end reverses the red-and-green relationship.
2. Find the threshold. Use the green transverse row and runway threshold markings rather than assuming that the first pavement is available for touchdown.
3. Look towards the far end. The steady red transverse row is the runway-end indication. White or yellow lights running lengthways are edge lights.
4. Separate steady and flashing lights. A pair of flashing white units near the threshold is a REIL installation, not the red runway-end row.
5. Check from the intended viewing angle. Directional lights may vanish from a drone, tower or side-on camera even when they display correctly from final approach or the runway centreline.

Why do runway light colours look wrong or disappear in a simulator?

The symptom usually reveals whether the problem is directional lighting, a global graphics issue or faulty airport scenery.

During a landing roll or rejected take-off, treat the steady red transverse row as the firm visual runway limit. Simulator scenery scale and light placement are not substitutes for calculated landing, take-off or stopping-distance requirements.