Steady Burning – Continuous Non-Flashing Light (Airport Lighting)

What is a Steady Burning Light?

A steady burning light is a type of aviation and airport lighting that emits a continuous, non-flashing beam. Unlike flashing or pulsing lights, steady burning lights remain illuminated at all times while powered, providing an uninterrupted visual signal. This makes them essential for marking the edges of runways, taxiways, and airport obstacles, as well as for delineating approach paths and ensuring the visibility of critical infrastructure.

Steady burning lights are mandated by international and national aviation authorities, including the International Civil Aviation Organization (ICAO) and the Federal Aviation Administration (FAA), for specific uses in civil aviation. Their deployment enhances operational safety, particularly in environments with complex layouts, low visibility, or high traffic.

Why Steady Burning Lights Matter

• Constant Visibility: Steady burning lights provide a reliable, always-on visual reference for pilots and ground personnel, reducing confusion and improving situational awareness.
• Compliance: International and national regulations (ICAO Annex 14, FAA AC 70/7460-1M) specify where and how steady burning lights must be used, especially for marking obstacles and airfield boundaries.
• Safety: By continuously outlining hazards and operational zones, steady burning lights play a crucial role in preventing collisions and runway incursions, especially at night or during adverse weather.
• Technology: Modern steady burning lights use efficient LED technology, offer low maintenance, and are engineered for durability in extreme environments.

Applications of Steady Burning Lights

1. Obstruction Lighting

Obstruction lights are installed on or near objects that could pose a hazard to aircraft, such as communication towers, buildings, wind turbines, and bridges. For structures up to 150 feet (45.72 meters) above ground level (AGL), low-intensity steady burning red lights (most commonly L-810) are used. For taller or more prominent structures, a combination of steady burning and flashing lights may be required.

Key Features:

• Color: Red (standard for low-intensity).
• Visibility: Must be visible from all directions (360°) and meet minimum intensity requirements (e.g., 32.5 candela for L-810).
• Placement: Top of the structure and at intermediate levels for tall or irregular obstacles.
• Regulatory Basis: ICAO Annex 14, FAA AC 70/7460-1M.

2. Runway Edge and Threshold Lighting

Steady burning white lights outline the edges of runways, while green lights mark the threshold (beginning) and red lights mark the end of the usable runway. These provide pilots with clear visual cues during approach, landing, takeoff, and taxiing.

Specifications:

• Runway Edge Lights: White, variable or fixed intensity, spaced typically every 60 meters (200 feet).
• Threshold Lights: Green (approach direction), red (departure direction).
• Durability: Weatherproof, impact-resistant, and suitable for all operational conditions.
• Power: Series circuits with backup systems for reliability.

3. Taxiway Edge and Centerline Lighting

• Edge Lights: Steady burning blue lights mark the edges of taxiways, helping pilots navigate between runways and terminals.
• Centerline Lights: Green, flush-mounted lights embedded in taxiway centerlines, used primarily at major airports and in low-visibility operations.

Regulatory Guidance:

• Spacing: 60 meters (200 feet) or less for edge lights; 15 meters (50 feet) or less for centerline lights.
• Color: Blue (edge), green (centerline).
• Integration: Forms part of the Surface Movement Guidance and Control System (SMGCS).

4. Approach Lighting Systems (ALS)

An Approach Lighting System uses both steady burning and flashing lights to create a “light path” extending from the runway threshold into the approach area. Steady burning white lights make up the primary visual reference, while flashing sequences enhance conspicuity.

• Purpose: Guide pilots to the runway during the final stages of approach, particularly in poor visibility.
• Coverage: Typically extends 420–900 meters (1,400–3,000 feet) from the runway.
• Regulation: ICAO and FAA prescribe specific configurations (e.g., ALSF-1, ALSF-2, MALSR).

Technical Standards and Compliance

ICAO Annex 14

ICAO’s Annex 14 – Aerodromes sets the international standard for airport lighting, including specifications for:

• Placement, color, and intensity of steady burning lights.
• Photometric and durability requirements.
• Maintenance and inspection protocols.

FAA Advisory Circulars

Key FAA documents include:

• AC 70/7460-1M: Obstruction marking and lighting requirements.
• AC 150/5345-43: Specification for obstruction lighting equipment (including L-810).
• AC 150/5345-46: Specification for runway and taxiway lighting fixtures.

L-810 Light: The Standard in Obstruction Lighting

The L-810 light is the industry standard for low-intensity, steady burning red obstruction lights on structures up to 150 feet AGL. It must:

• Emit at least 32.5 candela.
• Be visible from all directions.
• Use robust, weatherproof construction (IP65+).
• Be available in both AC and DC, with solar options for remote sites.
• Feature fail-safe monitoring and surge protection.

Failure to maintain operational L-810 lights can result in regulatory fines, NOTAMs, and operational restrictions.

Maintenance and Monitoring

Proper operation of steady burning lights is critical. Key best practices include:

• Routine Inspections: Check all fixtures for functionality, alignment, and cleanliness.
• Prompt Repairs: Immediately address any outages or malfunctions—regulatory authorities require NOTAMs for unserviceable lighting.
• Remote Monitoring: Increasingly, automated systems report failures in real-time.
• Record Keeping: Maintain detailed maintenance logs for compliance and audit purposes.

Power and Technology

• LEDs: Preferred for efficiency, lifespan (50,000+ hours), and low maintenance.
• Power Options: AC, DC, and solar-powered units are available.
• Environmental Protection: All fixtures must be resistant to water, dust, corrosion, and temperature extremes.
• Backup Systems: Generators or UPS ensure continuous operation during power failures.

Integration with Other Visual Aids

Steady burning lights are coordinated with:

• Flashing lights (for high-intensity warnings).
• Paint markings and signage.
• Spherical markers for cables and lines.
• Surface Movement Guidance Systems (SMGCS).

Regulatory Authorities

ICAO (International Civil Aviation Organization)

An agency of the United Nations that sets global aviation standards, including those for airport lighting. ICAO’s Annex 14 is the primary reference for steady burning light requirements worldwide.

FAA (Federal Aviation Administration)

The U.S. authority responsible for enforcing compliance with ICAO and national standards. FAA documents govern the design, placement, and maintenance of all steady burning lights in the U.S. airspace.

NOTAM (Notice to Airmen)

Any inoperative steady burning light (such as on a tower or runway) must be reported via a NOTAM to inform pilots and airspace users, ensuring continued safety.

Summary Table: Key Steady Burning Light Applications

Best Practices for Steady Burning Light Management

• Always use ICAO/FAA-compliant fixtures.
• Schedule regular inspections and cleaning.
• Implement remote monitoring for critical lights.
• Immediately report outages via NOTAM.
• Keep up-to-date maintenance and compliance records.
• Prioritize LED upgrades for efficiency and reliability.

Conclusion

Steady burning lights are a foundational element of airport and airspace safety. Their constant illumination ensures that runways, taxiways, and obstructions remain visible to pilots at all times, supporting safe aircraft operations under all conditions. Compliance with ICAO and FAA requirements is mandatory, and investing in reliable, efficient steady burning lighting systems is essential for any airport, heliport, or obstruction operator committed to safety and operational excellence.