If you manage or operate an aerodrome in Auckland, understanding runway threshold lights colour is foundational to CAA compliance. If you’re nothing of the sort and are someone who’s just into aviation, airport runway lights are a good addition to your knowledge base.
Every light in an airfield ground lighting system carries a specific meaning standardised under ICAO Annex 14 and enforced in New Zealand through CAA Part 139. Get the system wrong, and you’re not just failing an audit. You’re compromising every aircraft that uses your runway.
Quick Reference: Airport Runway Light Colours at a Glance
| Colour | Light Type | Meaning |
|---|---|---|
| Green (inbound) / Red (outbound) | Threshold lights | Start and end of usable landing surface |
| White, yellow in the last 600m | Runway edge lights | Runway boundaries and caution zone |
| Red | Runway end lights | End of usable surface |
| Bidirectional | Green/Red combination | Threshold end marker, one fitting for both directions |
| Blue | Taxiway edge lights | Taxiway boundaries |
| White and red combination | PAPI lights | Glidepath indicator |
Runway Threshold Lights’ Colours (Green/Red)
The threshold marks the start of the usable landing surface. Airport runway lights begin here. It’s the first system pilots read on approach, so correct installation and reliable operation are non-negotiable for any Auckland aerodrome.
Green threshold lights face landing aircraft. The same fittings emit red in the opposite direction for departing aircraft. This bidirectional setup is standard at Auckland Airport and across Auckland-region aerodromes, including Ardmore, eliminating the need for two separate systems.
Displaced Thresholds
A displaced threshold is where the usable landing surface begins further along the runway than the physical pavement start. Red edge lights mark the non-landing section. Green runway end bars mark where the usable surface begins. Taxiing and takeoff are permitted on the displaced section, but landing is not. If your Auckland aerodrome has a displaced threshold, the lighting configuration must reflect this accurately under CAA Part 139.
RTILs and REILs (Flashing White Light)
RTILs (Runway Threshold Identification Lights) are two synchronised flashing white lights on either side of the threshold. They make the runway start visible at night and in low visibility. REILs (Runway End Identifier Lights) also flash white and identify the runway end on final approach. These are two distinct systems with different compliance requirements. RTILs mark where the landing surface begins. REILs mark where it ends.
Runway Edge Lights (White Turning Yellow)
Runway edge lights define the full lateral boundary of the runway. They’re white for most of the length, turning yellow for the final 600 metres as a caution zone that warns pilots the runway end is approaching.
Auckland Airport operates High Intensity Runway Lights (HIRL) with variable-intensity controls. Medium Intensity (MIRL) systems at regional aerodromes in the Auckland area also use variable controls. Low Intensity (LIRL) systems at smaller NZ airstrips operate at a fixed setting. The correct intensity classification is determined by your aerodrome’s CAA category. Installing the wrong system is a compliance issue, not just a technical one.
Need to know more about compliant airfield lighting systems for your Auckland aerodrome? Our team at Up N Atom Electrical installs and maintains AGL systems across New Zealand.
Runway Centreline Lights (White and Red)
On precision instrument runways at Auckland Airport, centreline airport runway lights are embedded into the surface at approximately 15-metre intervals. The colour sequence gives pilots a distance countdown that is readable under any visibility condition.
The lights are white until 900 metres remain. They alternate red and white for the next 600 metres. For the final 300 metres, all centreline lights are red. Smaller NZ aerodromes and private airstrips generally don’t require centreline lights. They’re a precision instrument runway specification.
Touchdown Zone Lights (White Light Bars)
Touchdown zone lights (TDZLs) are two rows of steady white light bars placed symmetrically across the runway centreline. These usually start approximately 30 metres beyond the landing threshold and extend to around 900 metres or the runway midpoint.
TDZLs are a precision approach runway requirement. They help pilots confirm the correct touchdown point and judge flare height in low visibility. If your aerodrome holds a precision instrument rating, they’re part of your compliance picture.
PAPI Lights: Glidepath Indicators (White and Red)
PAPI (Precision Approach Path Indicator) lights are four fittings positioned beside the runway and help check if the glidepath angle is good enough. Here’s what they mean:
- All white means too high.
- Two white and two red means on the correct glidepath.
- All red means too low.
Some Auckland-region aerodromes still run VASI (Visual Approach Slope Indicator), an older two-bar system that serves the same function. PAPI calibration and positioning must meet ICAO Annex 14 tolerances. Incorrect alignment directly affects the approach safety on your runway.
What happens if a glidepath angle is too high or too low?
Too high (above 3 degrees) – The pilot risks touching down too hard, too fast, or overshooting the touchdown zone. In a worst case, the aircraft lands long and runs out of runway during rollout.
Too low (below 3 degrees) – The aircraft may not clear obstacles or terrain on the approach path before reaching the runway. It also risks touching down short of the threshold, before the actual runway surface begins.
Taxiway Light Colours (Blue, Green, Amber, and Red)
Understanding airport runway lights means understanding what surrounds them, too.
Blue edge lights define taxiway boundaries and distinguish taxiway surfaces from runways at night.
Green centreline lights guide the aircraft’s path, which is essential in a complex layout like Auckland Airport’s multi-taxiway network. Lead-on and lead-off lights alternate between green and yellow at runway entry and exit points, warning that the aircraft is within the runway environment or the ILS critical area.
Clearance bar lights are amber at holding positions and intersections, signalling pilots to stop and wait for ATC clearance. Stop bar lights are red at runway crossings and extinguish when clearance is given, with green centreline lights ahead illuminating to confirm the aircraft can proceed.
Runway guard lights flash amber on both sides of any taxiway crossing a runway. Each has specific installation and maintenance requirements under CAA Part 139.
Lighting at Smaller Auckland-Region and NZ Aerodromes
CAA NZ Part 139 sets minimum lighting standards by aerodrome class. A smaller Auckland-region airstrip may only require basic threshold markers and low-intensity edge lights, but those requirements are still mandatory.
Many smaller, unattended NZ aerodromes use Pilot Controlled Lighting (PCL), where pilots activate runway lights by keying their radio mic to the correct frequency. PCL systems still need regular testing and compliance documentation like any other AGL component.
If you manage an aerodrome in the Auckland region and aren’t confident your lighting meets current CAA requirements, we can help. Up N Atom Electrical specialises in aerodrome electrical services across Auckland and the wider New Zealand aviation network.
Frequently Asked Questions
In New Zealand (including Auckland), what do runway light colours mean?
Airport runway lights act as a visual language for pilots to ensure safe takeoffs and landings. In New Zealand, these colours are standardised to provide critical information about the runway’s boundaries and remaining distance. Green generally indicates the start of a runway (threshold), white marks the main runway edges, and red signifies the end of the usable surface. These standardised signals are essential for maintaining safety at all NZ aerodromes, from major hubs like Auckland to smaller regional strips.
What colour are runway edge lights supposed to be, and what do they indicate?
Runway edge lights are typically white. Their primary purpose is to outline the lateral limits of the runway during periods of darkness or restricted visibility. On instrument runways in New Zealand, the white lights may change to yellow for the final 600 metres (or the last third of the runway) to provide a caution warning to pilots that they are approaching the end of the runway.
What are runway threshold lights and threshold identification lights (and what colours are they)?
Runway threshold lights colour plays a key role in helping pilots identify the touchdown point. Threshold lights are a row of green lights that mark the beginning of the portion of the runway usable for landing. These are accompanied by Runway Threshold Identification Lights (RTILs), which are two synchronised flashing white lights positioned on either side of the runway threshold. Together, these green and flashing white lights help pilots quickly identify the touchdown point when approaching a runway at night.
Why do some approach lighting systems use combinations of white, red, and yellow at major airports?
Complex airport runway lights systems use different colours to guide pilots from the approach path to the runway touchdown zone. White lights are generally used for the main approach, “carpet”, and crossbars. Red lights are often used on “side row bars” to alert pilots that they are outside the lateral confines of the touchdown zone or reaching the overrun area. These colour combinations provide the necessary depth perception and alignment cues required for safe landings in low visibility.
What is the difference between runway edge lights and centreline lights for NZ aerodromes?
The main difference lies in their placement and the specific guidance they provide. Runway edge lights are located along the sides of the runway to define its width. In contrast, runway centreline lights are embedded into the actual runway surface along the middle. At many NZ aerodromes, centreline lights are white until the last 900 metres, where they alternate red and white, eventually turning all red for the final 300 metres to indicate the runway end is imminent.
How do pilots use runway lights in low visibility and night operations at NZ airports?
Pilots rely on airport runway lights for spatial orientation and distance awareness when the natural horizon is not visible. The specific patterns and colours allow pilots to verify their alignment with the runway, judge their height above the ground via PAPI lights, and determine how much runway remains for braking or takeoff. High-intensity lighting is particularly crucial at busy airports like Auckland to maintain operational flow during fog or heavy rain.
Who maintains runway and aerodrome lighting systems in New Zealand?
Maintenance of airport runway lights is performed by specialised electrical contractors, like Up N Atom Electrical, who have the training to work in high-security airside environments. Maintenance involves:
- Cleaning and Levelling: Ensuring light beams are aimed correctly and lenses are clear.
- Insulation Resistance Testing: Checking cables for leaks or faults to prevent circuit failure.
- Component Replacement: Replacing lamps and transformers to ensure 100% uptime.
- Compliance Checks: Verifying the system meets CAA NZ and ICAO standards.
Running An Auckland Aerodrome And Need A Compliance Check?
Every airport runway light on your aerodrome is subject to a compliance requirement. A miscalibrated PAPI, an incorrect intensity classification, or an undocumented PCL system can put your CAA certification at risk and compromise the safety of every approach made to your runway. Getting it right isn’t a one-time install job. It requires regular testing, accurate documentation, and an electrician who understands the airside environment.
There are many more lights at an airfield, but we’ve touched upon the most common ones. At Up N Atom Electrical, we specialise in a wide range of services for the aviation industry, including the installation and maintenance of an airport runway lighting system. As expert electricians, you can count on us to provide exceptional solutions, delivered at the highest of standards – we can ensure that your airport runways are ICAO and CAA compliant.
Our licensed aviation electricians install, maintain, and certify airfield ground lighting to NZ’s legal standards. Call us on 021 0240 3992 or request a quote today.
