Illuminating the way forward

posted on 26th June 2018

Airfield lighting is at the forefront of financial, environmental and safety considerations facing modern airports, despite or perhaps because of successive innovations in lighting technologies. Bernadeta Tendyra reports

Advances in halogen and particularly LED lighting (not to mention solar and other options) are giving airports increasing numbers of alternatives; however, technological progress is also placing them under pressure to modernise lighting infrastructure.

Conversely, the often low time between overha  ul (TBO) characteristic of existing halogen lights, as well as the innate and perhaps understandable conservatism of airport managements, which have to be convinced of the merits of costly and long-term lighting systems, can slow the pace of change.

Yet the airports that have embraced new lighting technology, or are in the process of doing so, have generally been satisfied with the results. Halifax Stanfield International in Nova Scotia, Canada, has exploited recent renovations to embrace LED and other lighting fixtures. “We have converted some of our signage, and we’ve also incorporated some LED taxiway lights,” says Jeff Macmillan, senior manager, airport facilities and airside services, Halifax International Airport Authority (HIAA). “So far we’ve had pretty good luck… as you drive towards a sign, it has a much crisper, cleaner presentation from each angle.”

As older lighting fails, Halifax Stanfield is also converting runway guard lights, which prevent incursions at the junction of taxiway and runway. Safety and superior presentation apart, LED lighting requires limited maintenance, is two to five times more efficient than halogen, and minimises costs across the board.

ADB Airfield Solutions has manufactured much of the new lighting at Halifax Stanfield, alongside Prosign, Youyang Airport Lighting Equipment Inc. and others. “We have a sound relationship with ADB, Macmillan informs. “They have a good product, they support it very well, they are very knowledgeable, and the price is comparable to other manufacturers’ in all cases.”

Nancy Majoulian, national sales manager for Canada at ADB Airfield Solutions, refers to ADB’s 65 years of “offering advanced, integrated and sustainable solutions for visual guidance”.

She also raises the “missing link” in ADB’s portfolio – a high-intensity, inset, elevated and recently certified runway edge light: “… a lot of airports have been enquiring about this product because it helps them complete upgrading to LEDs on their runway“.

LEDs increase safety, Majoulian argues, because they require less maintenance and fewer journeys on the airfield by repair vehicles, reducing the risk of incursions. LEDs also maintain their lumen for much longer than incandescent lighting.

“We have several reports showing that LED fixtures are more conspicuous and crisp,” she adds. “The photometrics have to meet the exact same standards as incandescent fixtures.”

Moreover, LED signs are also “more uniformly illuminated than conventional signs, providing optimal pilot visibility”, Majoulian asserts.

In September, ADB launched a new range of AD-lights at the Inter-Airport China 2012 exhibition in Beijing. The DTS/DTC taxiway lights and stopbar lights have very low energy consumption (typically 11 watts for a single-plug, bidirectional light and 9 watts per side for a dual-plug light, compared to 40 watts for halogen lights). They also promote traffic efficiency and availability of taxiways, thanks to a substantial reduction in maintenance.

Solar power

Halifax Stanfield is meanwhile hosting a JSF Technologies trial of solar-powered signage, involving 24-hour stop-sign flasher beacons located on crash response roads. This embraces both LED and solar-powered lighting, the latter involving Photovoltaic technology that converts sunlight into electricity using photovoltaic cells, with the ‘PV’ effect exhibited via semiconductors.

“Using solar lights minimises costs for everything,” says Jack Foster, president of JSF Technologies. “Because they are autonomous units, they do not require digging up pavements or tapping into the electrical grid. Installation is brief and needs no additional labour. Once installed, the LEDs have no electricity or labour costs.” The intensity of solar lights can be altered during manufacture.

In October, another Canadian gateway, Toronto Pearson International airport, purchased 16 units of the Solar Series JSF LED Beacons as 24/7 warning devices, together with stop signs located throughout the airfield independent of the electrical grid, reveals Aviation Renewables, the aviation consultant for JSF Technologies and for the Halifax Stanfield solar project.

Toronto opted for the Solar Series FL-1412 Northern Model, which provides a 12” signal, large solar panels and additional battery capacity. It can operate 24/7 for four months without sunshine, and by using Solar Series FL-1412 beacons, the airport can illuminate all stop signs day and night independent of runway and taxiway lighting. The latter can be turned off when not in use, reducing energy, maintenance and operating costs.

In 2008, HIAA expanded its Liberty Airport Systems (LAS) Freedom Series ALCMS to accommodate Transport Canada requirements for Low Visibility Operations when Runway Visual Range (RVR) conditions drop below 2,600ft visibility, informs Don Gordon, LAS vice-president, Canadian sales.

Located on the Atlantic coast and frequented by heavy fog, the airport was mandated to install stopbar and taxiway lead-on/lead-off lights on the main runway. Liberty supplied SafeGate-brand individual lamp controllers for the stopbars and taxiway inset fixtures, and modified the ALCMS System to provide Stopbar Control and Monitoring displays for air traffic controllers. It also deployed microwave transceivers on the airfield to sense aircraft location in and around the stopbars.

Halifax controllers could thus safety manage multiple aircraft in CAT II conditions, keeping airport operations running and punctual in the worst weather conditions. With the PLC controllers and HMI touchscreens in situ, an expansion of the ALCMS System in 2010 and 2012 added new circuits at a fraction of the cost of the original infrastructure. Laptop PCs working with either the airport’s Wi-Fi network or on a dedicated ethernet now provide operations and maintenance personnel with mobile wireless airfield light monitoring and control.

Investment at Brisbane

Over the past 24 months, Australia’s Brisbane International airport has placed LED fittings in various new installations. “It’s an ongoing part of our maintenance programme progressively to replace halogen taxiway centreline lights with LED fittings and retrofit the Movement Area Guidance Signs (MAGS) with LED components,” says Krishan Tangri, general manager, assets, Brisbane Airport Corporation.

Inset taxiway centreline lights, installed on their own electric circuit in the same way as traditional halogen taxiway lights, are the airport’s main LED-type component. A standard 6.6A CCR runs the circuits, although some LED manufacturers use a much lower current that requires a specialised CCR and control.

Three lighting companies service different parts of the airport. ADB LED taxiway centreline fittings and ATG LED Movement Area Guidance Signs feature in front of the international terminal on the eastern side of the airfield. SafeGate LED taxiway centreline fittings and SafeGate LED MAGS are found in front of the domestic terminal on the eastern side. The western side of the airfield close to the maintenance hangers hosts ATG LED taxiway centreline fittings.

Brisbane Airport Corporation has also installed elevated taxiway edge lights on the newly constructed sections of the international and domestic terminal aprons. The airport has signalled its intention to convert existing MAGS to LED-type next year.

“State-of-the-art lighting and signalling systems increase safety at airports, with the addition of individual remote light monitoring, stopbars and visual telemetry, etc,” Tangri argues. Air Services Australia is currently installing the Advanced-Surface Movement Guidance Control System (ASMGCS), capable of monitoring the exact position of aircraft and vehicles on the movement area.

Brisbane airport uses solar-powered lights for non-permanent installations such as temporary taxiway edge lighting, and to mark unserviceable or closed taxiways and aprons. The Thorn Avilite AV70 2010 solar aviation light is fast and easy to deploy, has an integrated solar/battery system, dual internal high-performance solar modules angled to maximise solar collection, a tough LED, UV-stabilised LEXAN polycarbonate aviation lens with 0 to +10 degrees’ vertical divergence and light base, automatic night activation, a user-replaceable battery in a sealed compartment, a band of retro-reflective tape and ultra-high intensity LEDs.

It is deployed typically as a Solar Airstrip, Barricade, Caution, Taxiway (ICAO), Threshold and Obstruction Light. A hi-intensity version, the AV70-HI, is designed for use in areas receiving a minimum of 3.5 hours of sun per day. The AV70-RF is a radio-controlled version of the AV70.

“BAC is committed to an active response to the long-term impacts of climate change and minimising adverse environmental impacts on aviation and property development activities,” Tangri states.

Preliminary plans are also being laid for a major expansion of Brisbane airport, and Mike Fisher of Airport Lighting Specialists, UK-based ATG’s supplier in Australia, anticipates offering ATG’s new IRIS lights, which he describes as an “exciting innovation in the field of airfield ground lighting.”

According to an ATG Airports spokesperson: “The new ATG Airports IRIS LED Runway and Taxiway fitting is a third-generation LED airfield lighting fixture. It has a number of unique design elements, ranging from the low-protrusion profile to the extremely efficient, low-energy consumption electronic technology used to maintain the correct light output at all times.

“The innovative design uses common components across the entire IRIS inset range, thus reducing the number of individual spare parts required to be held in stock by airport maintenance. This reduction in numbers of spares, along with the optimised power consumption of the electronic circuitry, helps to prolong the lifespan of the LED’s in the IRIS fittings, offering longer maintenance intervals, fewer spare parts and reduced lifecycle costs.

“When the IRIS range of inset fittings is rolled out into the airport environment in early 2013, we expect airfield LED technology to be raised to a new level,” the spokesperson adds.

Chopin considers the alternatives

Poland’s Warsaw Chopin International airport is also open to new technologies, reducing carbon dioxide emissions and electricity consumption. However, the low TBO of existing halogen lights at runways and taxiways means that the “simultaneous replacement of all existing fixtures with LED technology is not planned”, says Przemysław Przybylski, Warsaw Chopin airport spokesman.

ERNI of Switzerland, ADB, NKI of the Netherlands, Finland-based OBELUX (LED obstruction lights) and Airfield Signs (now owned by SafeGate, Sweden) supply lighting to the airport. “We’ve been a strong partner for Warsaw Chopin airport, a long-time supplier of LED signs, and we’ve been testing LED runway centre and elevated lights,” Sergei Loukianov, ADB’s sales manager for the region, asserts.

“It’s a very advanced, technological airport and we are pleased to contribute to increasing its safety and efficiency.”

New airport projects planned for 2013-15 include incorporating LED technology in all navigational lighting systems. “Thanks to their pure, monochromatic colours, LEDs meet intensity and colour requirements while consuming less power,” Przybylski observes. “A greater challenge is the application of LED technology to high-intensity lighting systems at runways, such as centreline, touchdown and approach lights.”

He points out that LEDs need expensive spare parts, and due to their lower temperature, they do not melt snow/ice in front of the prism in cold conditions, requiring immediate and precise removal of deposits from inset lights. Given the low number of sunny days per annum at Chopin airport, Przbylski believes that solar-powered, illuminated signs and obstacle lights, and particularly navigation lights, have no justification, although such fixtures cannot be completely ruled out in the future.

He also sees no correlation between the use of LED lights and improvements in operational safety, as the LEDs must meet the same requirements of Annex 14 in respect of colour, beam distribution and intensity as halogen lights; however, due to the monochromatic feature of LED lights in low visibility conditions, LEDs’ colour is clearer than for halogen equivalents in the same conditions.

Advances in technology, increasing demands on air transport, and the search for solutions to some of aviation’s biggest safety and eco-challenges are undoubtedly pushing airfield lighting forward. However, the often low TBO of existing halogen lights, the cost of replacement with LED and other options, and the caution of airport authorities facing significant, long-term financial outlay on new products, will mean that change will be gradual.

Flex-O-Lite marks the way

Flex-O-Lite, Inc – a St Louis, US-based division of Potters Industries Inc – is a leading manufacturer of reflective glass beads and is best known in the aviation industry for its Type III airport glass bead.

Aiming to reduce numbers of runway incursions by providing the best possible runway and taxiway markings, Flex-O-Lite notes that Type III beads provide up to seven times the reflectivity of their Type I counterparts.

According to the company: “Type III airport bead efficiency saves time and money, while providing the brightest and safest airfield markings available”.