All Lit Up
Consistency is the hallmark of any light, be it in a bedside lamp or at 30,000 feet, but the technology behind lighting has gone through a handful of iterations. Halogen, xenon and fluorescent are all giving way to what is becoming the norm — LED.
“LED is probably the most widespread technology that you'll see being used for the next decade,” said Bob Lenz, product line director for aerospace lighting at Honeywell.
Honeywell, who Lenz said were one of the first companies to start developing and selling LED lighting, are now on their fifth generation of LED lights. First developing and selling their LEDs in 2001, Lenz said that each new generation of lights since has increased LED’s benefits, making them an increasingly attractive lighting solution. “What's different about the fifth generation than our previous generations? I'd characterize it by three different things: Number one is improved LED power and efficiency. Number two is integrated power supplies and number three is reduced weight. With each successive generation of LEDs, they get better and better,” Lenz explained.
The greatest benefit of LEDs, Lenz said, is the cost savings. “The most obvious benefit is the reduced operational and maintenance costs. In an LED lighting solution, you can get anywhere from 10 to 100 times the increase in service life over a comparable legacy technology. You also get improved pilot and aircraft visibility, reduced power consumption, reduced size and weight. And with that reduced size and weight, you can sometimes get to — and this is like one of the hallmarks of our fifth-generation — up to a 50 percent reduction in size and weight with the smaller LED packaging and our integrated power supplies,” Lenz described.
Looking at the market, Philip Odackal, vice president and general manager of lighting solutions for Collins Aerospace, said that the industry is focused primarily on power, weight and reliability — all advantages of LED. “As we've completely shifted into LED, we're drastically reducing the power draw that lights take on. The reliability goes up because the longevity, as you've seen on the ground for LED lighting, continues into the air. Then the weight also comes down as you take out some of the mechanical complexity that you have with a traditional light,” Odackal said.
Steve Scover, general manager of lighting solutions, interiors for Collins Aerospace, said that their business started primarily as a fluorescent lighting provider in serving the business jet market. “As technology has evolved, fluorescent became something of the past and we've been developing LED systems both for interior, as well as exterior. From an interior perspective, I think LEDs have certainly become the norm. That is, what every aircraft is rolling off the assembly line with right now. Much of the retrofit community has also adapted LED technology,” Scover pointed out. “I think when an operator or an airline is looking to differentiate themselves in a cost effective manner, they turn to lighting.”
For the 15 years that Scover has been at Collins, he said the company has done nothing but LED design, though they still offer other types of lighting in a support role. For Honeywell, Lenz echoed that statement. “All of our new lights that we develop are LED, but we still ship an extraordinary number of halogen lighting solutions. And when we're talking about anti-collision lights, that’s mostly xenon lighting solutions. So, those are still present in many aircraft worldwide and we support those throughout the life of the aircraft,” Lenz explained.
Making the switch from halogen or xenon lights to LED can range, Lenz said, from very easy to requiring some aircraft modification. “The installation will depend on the design of the LED lights. So, a good example is we have a new Boeing 737 fuselage collision light that we’re now selling through one of our authorized distributors, Aviall. That is a light that we've designed to be a complete drop in replacement for the existing fuselage anti-collision lights on the 737s, and we can say that with certainty because we produce the existing halogen xenon 737 anti-collision light. We’ve designed it so you literally can pull one out and then install the new one,” Lenz said.
In this case, Lenz noted, the only difference is the existing light has a separate power supply, whereas the LED has an integrated one. Honeywell sells what they call a Cable Interface Adapter, that the existing cabling plugs into and connects to the light. No new cabling is required and the entire LED light installation process takes 15 minutes
Odackal said that making the switch to LED can be complicated due to the differences in technology, but they do their best to minimize the differences, and thus downtime. “You're typically having a degree of switching here that you recoup through the payback of the enhanced product, either in performance or operational costs. It's similar to if you're in your home and you do a re-lamping project. The state will give you a number of incentives. The individual LED bulb is slightly more expensive, but the operating cost is lower. So, the net benefit to you over time certainly encourages you to transition to LED for both quality and durability,” he explained. “Generally speaking, you're not talking about a large overhaul if you're going to upgrade your lighting solution. This is something that can be done with a degree of relative ease.”
The Full Spectrum
LED’s industry dominance isn’t merely limited to the commercial side. It has grown into the go-to for business and general aviation operators, for many of the same reasons.
“Most of our King Air customers are seeking to minimize power draw from incandescent lights,” explained Eric Dahlinger, outside sales manager for PWI. “If you're not using the power, you're not running the generators run by the motors, causing higher fuel consumption. It's this cascade effect. If you've got bulbs that require more power, that requires more output from the generator, which requires more input from the motors running the generators.”
Another key aspect for PWI’s customers making the switch to LED is the reduced heat of light compared to the fluorescent lights most of their customers have. Though largely, Dahlinger said, it is the reduced maintenance time and costs that LEDs incur that’s their most attractive aspect. “There's just the ongoing maintenance of it. Regardless of what light product it is, whether it's fluorescent or something else, eventually you're going to have some sort of failure there. The tube is going to go out. The power supply may go out over time,” Dahlinger described. “The LED industry has defined a LED failure when the brightness drops 30 percent. That's a failure. I might know people that would not, over the course of 10 or 15 years, notice only a 30 percent drop. LEDs don't burn out like a bulb does; the filament burns through them, that's it. No more light. LEDs will slowly, just ridiculously slowly, glacially slowly, fade over time until you turn them on and you just don't get any light at all. But that's years and years — 100,000 hours of service.”
And, while those benefits of LEDs are shared between the commercial and general aviation side, the creative potential of the lights can be fully realized by private aircraft owners who use LED technology to endow their planes with their own unique style.
The ability to control the color of their cabin is exactly what Elliot Technologies is offering in it’s new lighting solution — PRIZM Cabin Lighting — which harnesses the power of LED technology to offer millions of color combinations, instantly changeable at a flyer’s fingertips through the lighting’s app. “What makes the lights extremely unique is the ability to control them from any kind of carry on device. You can still have your hard switches, and they'll work with existing momentary ground, momentary relays and they'll work with existing switches on the airplane,” described Tim Lockerby, product sales manager for Elliot Technologies. “But what makes us really unique is the full color; it has millions of colors. It's full RGBW, so it's full red, green, blue and white.”
PRIZM has been available for three years and is a fully scalable lighting solution. “It'll work in anything. We have it in King Airs, Hawkers and Citations. And, because we're still newer, we're quoting it out right now for some Globals, Gulf Streams and Challengers,” noted Lockerby.
Like other LED installs, the process to installing PRIZM will depend on the aircraft and what the operator is looking to have done. “We've had a few customers that want to keep the floor lighting and they just want to do some downwash up top. So, it's going to be different for every airplane,” Lockerby explained. Though, he said that the time to have lighting work done is the same time as other interior work.
“When the interior's opened up, it's pretty straight forward, just putting the LED light strips in. Another advantage of this is our LED light strips come in up to 16 feet of length, so you could avoid some of those little gaps of lights. If you have the whole interior removed and you got a fuselage length, you need about 14 feet of run length, you could do that in one continuous strip. So, you wouldn't have to use three six foot strips or something like that,” Lockerby said.