LED Aviation Lighting

Company Dialight
Date 05.01.2011

LED Obstruction Lighting Systems Give Back
By Michael Schratz

Director of Marketing – Dialight Corporation

When considering all the many lighting applications that require a simple lamp change, the top of a wireless telecommunications or antenna tower stands out as one you may prefer to avoid. However, the extreme repercussions for a failed obstruction lighting system constantly haunt tower owners as they have civil responsibilities to warn pilots in order to avoid aeronautical accidents. With years of incandescent lamp failures, and the possibility of a future ban of this aging and energy-hungry lighting technology, tower owners are faced with expensive decisions to make.

Regulations set forth by the Federal Aviation Administration (FAA) force tower owners to modernize outdated lighting systems comprised of older technology such as incandescent bulbs and xenon tubes. The fines associated with light failures and the inherent safety risks involved outweigh the cost of maintaining existing lighting systems. If a tower owner has repeated failures and a history of non-compliance, the fines can sometimes be five times higher than those for the first-time offender.

Some may not realize that there has been a viable lighting alternative for marking aviation obstructions for almost ten years. Light emitting diodes, or LEDs, are the technology behind modern aviation obstruction lighting systems. For years, LEDs have been utilized in rugged applications such as traffic and railroad signals, where a failure can be catastrophic. Approximately 70% of traffic signals in the United States have been upgraded to LEDs as mandated by the Energy Policy Act of 2005 as the only technology approved for cities and municipalities to legally purchase moving forward.

LEDs are semiconductors which are solid-state devices that require little power and generate little heat. As they do not rely on a fragile filament for illumination, they are resistant to shock and vibration which gives them a long lifespan. Well able to handle extremes of climate, they utilize precise optical control to avoid light spill and contain no mercury or harmful materials.

A common misconception with LED systems is that the cost outweighs the benefits, and that these systems are too expensive. While the upfront cost of a new LED system may seem expensive, the actual lighting system hardware is only part of the total cost of ownership equation. Taking into consideration the reduced need for scheduled tower climbs, energy consumption, emergency repairs, replacement lamp costs and painting, LED lighting systems typically pay for themselves in as little as 2- 4 years. Even so, only 5% of the industry has made the switch to an all-LED system.

Current trends in the market
Tower owners nationwide are beginning to migrate away from type-A painted towers (which only require L-864 red lighting at night) toward type-C, D, E or F non-painted towers, which replace the “candy cane” paint style with an L-864/L-865 dual red/white lighting system for either night or day use. Since the introduction of an all-LED L-864/L- 865 dual red/white system in 2007, mass deployment has begun with some of the larger tower companies having made commitments to install only these systems going forward.

Prior to a legislative ban, towers primarily used lead-based paint for visual markings during the day. Now, tower owners are facing significant challenges for existing towers with this paint type. For environmental purposes, repainting a tower previously marked with lead paint means the added responsibility of ensuring that not one flake of paint chipped away touches the environment. Faced with the potential of re-painting the tower every 5 to 7 years, tower owners can expect to spend a whopping $20,000 for each of these environmentally-friendly facelifts. Meanwhile, an LED system will operate reliably throughout this time period, with no added maintenance costs. In these situations while a dual L-864/L-865 LED system may be deployed to establish compliance, the old paint may remain on the tower and the payback period for an LED system becomes even more attractive.

The cost of unreliable lighting technology
The repercussions for a failed obstruction lighting system can be quite costly, in some cases reaching $25,000 in fines. The FAA requires that a light failure be reported immediately so that a “NOTAM” (Notice to Airmen) can be issued advising aircrafts of the outage and location. The FAA routinely alerts Federal Communications Commission (FCC) field offices when tower owners fail to report that lighting outages have been repaired within the 15 day NOTAM window. Recent decisions by the FCC’s Enforcement Bureau state that failures for even a single day of non-operational tower lights will result in a fine.

Between January 2008 and August 2010, there have been 27 fines imposed for failed lighting systems, improper monitoring of lighting systems and/or improperly painted towers, resulting in nearly $300,000 in fines–all of which could have been avoided with a reliable LED lighting system. (http://www.fcc.gov/eb/broadcast/asml.html)

Long life – The key to a quick payback term
LEDs will last a long time, but only if the product design is engineered correctly. The key is to manage heat dissipation: keep the LEDs running cool and they will last for years. Unlike other lighting technologies, LEDs love cold weather. Most LED-based obstruction lighting systems ship with a standard 5-year warranty, but will most often last upwards of 10 years. Since LEDs are semiconductor technology, they can be managed easily, networked with GPS, making the monitoring of units quite simple.

Energy savings
Compared to wasteful L-864 incandescent beacons that consume 1400 Watts, the latest LED beacon equivalent consumes only 20 Watts, or roughly 98% less energy. L-864/L-865 Xenon dual beacon systems consume up to 390 Watts for day mode (white), and 490 Watts for night mode (red). This is reduced with an LED system to 90 Watts for day mode and 35 Watts for night mode. Meanwhile, the L-810 side marker lights reduce consumption from 116 Watts to 8.5 Watts. 

Recent LED product improvements
With recent efficiency improvements for both red and white LED technology, the products are becoming significantly smaller, which means a significant reduction in wind load. For example, the recently introduced Dialight Vigilant Series L-864/L-865 LED Red/White Dual Beacon stands at only 7”, where the typical xenon / incandescent units installed in field are roughly 28”.

Photo caption: Dialight’s latest Vigilant Series LED L-864/L-865 LED dual red/white beacon is 75% smaller, 10 lbs. lighter and up to 95% more energy efficient than traditional Xenon based dual beacons.

Photo caption: Dialight’s progression of LED technology from 2001 to present with LED L-864 red beacons. With the improvements of red LEDs over the years, the product size has been reduced by more than half and energy consumption has dropped from 200 Watts to 20 Watts to help tower owners benefit from a faster payback.

Photo caption: The quickly evolving white LED technology has enabled Dialight’s latest Vigilant Series L-864/L-865 LED dual red/white beacon to significantly reduce the number of LEDs per unit, allowing for a smaller mechanical design, less thermal management and even further reduction in energy consumption.

The future of the technology
High-brightness white LED technology has grown by leaps and bounds over the past few years, but the industry is on the cusp of something extraordinary. The most efficient
LED on the market today is 130 lumens per watt, but recent announcements suggest that in 2011, 160 lumens per watt LEDs will be commercially available. So what does that mean for tower owners and LED obstruction lighting?

The current state of LED product development makes this technology available only for certain towers, leaving non-painted towers above 500’ unable to reap the same benefits. However, with the recent improvements in LED lighting technology, an L-856 high-intensity lighting system is almost a reality. Towers utilizing this type of lighting system can soar up to 2200’—a very difficult height to reach in order to change out a lamp.

FAA Tower Lighting Requirements

Typical A1 Tower
(150’ – 300’, painted)
Lighting Requirements:

(1) L-864 Red Beacon, 50% “on” time

(2) or (3) L-810 Red Side Marker Lights, 50% “on” time

Typical A2 Tower
(351’-700’, painted)
Lighting Requirements: 

(3) L-864 Red Beacon, 50% “on” time

(6) L-810 Red Side Marker Lights, 50% “on” time

Typical D1 Tower
(200’-350’, non-painted)
Lighting Requirements: 

(1) L-865 White Beacon, 50% “on” time

Typical D2 Tower
(351’-500’, non-painted) Lighting Requirements:

(3) L-865 White Beacon, 50% “on” time

Typical E1 Tower
(200’-350’, non-painted) Lighting Requirements:

(1) L-864 / L-865 Dual Red / White Beacon, 50% “on” time

(2) or (3) L-810 Red Side Marker Lights, 50% “on” time

Typical E2 Tower
(351’-500’, non-painted)
Lighting Requirements:

(3) L-864 / L-865 Dual Red / White Beacon, 50% “on” time

(6) L-810 Red Side Marker Lights, 50% “on” time

Notes:

  • All payback calculations are based on an energy rate of $0.11 kWh.
  • No calculations take into consideration scheduled tower painting,which may cost upwards of $20,000 and would drive the payback down even further.

Contact

Dialight
Exning Road
Newmarket
Suffolk
UK
CB8 0AX
  • + 44 1638 665 161