Sometimes the only saving grace for mariners at sea is a single beacon of light emanating from the shore, a signal that has changed over time and continues to transform as technology evolves. From coastal bonfires of earlier times to energy-efficient bulbs of today, light has always served as an onshore beacon guiding ships to safety and welcoming weary sailors home.
As keeper of the light, the Coast Guard consistently seeks new ways to improve existing systems of navigation. In 2007, an initiative was introduced to enhance the reliability of current navigation aids and reduce environmental impact, notably, through reduced maintenance and solar power generation.
Nationwide the Coast Guard maintains roughly 50,000 coastal aids to navigation.
Hawaii has a unique relationship to the sea and its own share of navigation aids marking the ports and waterways around the state. Ensuring those aids remain visible is the job of six Coast Guardsmen who comprise the Aids to Navigation Team, Honolulu. ANT Honolulu is responsible for maintaining all fixed navigation aids for Hawaii. To them, the new initiative means less maintenance, more dependability. The ANT crew regularly travels to eight of the Hawaiian Islands conducting routine maintenance and conversions for 99 lighted land-based navigation aids. Recently, several of those aids were converted to new light-emitting diodes, more commonly known as LED.
Reliability of navigation aids is especially important in Hawaii where 75 percent of America’s coral reef is located. Aids not only protect mariners, their cargo and vessels, they also ensure navigation routes are clearly marked around Hawaii’s delicate reef ecosystems.The self-contained LED lanterns encase a battery, solar panel and light in one unit. These units reduce the amount of time required for maintenance and minimize the occurrence of personnel errors associated with servicing them. They also eliminate the potential for weather erosion due to the casing in which the components are housed.
In traditional incandescent lanterns, an automatic light-changing device rotates a series of six bulbs into place as each burns out. These bulbs contain filaments, a separate solar panel recharging the battery packs and exterior wiring exposed to outside elements. Instead of servicing the bulbs, changer, filaments and wiring, the entire system is removed as part of the maintenance process.
“LED conversion is good because it saves power, saves money on maintenance and saves time,” said Petty Officer 2nd Class Chad Dunlap, an electrician’s mate with ANT Honolulu.
The way the LED units work, explained Dunlap, is when the lighted aid is taken off commercial power a battery is installed. That battery powers the light and solar panels recharge the battery. The batteries have a longer life cycle, the units are self-reliant and protected from the elements, and they consist of fewer components, cutting down on the cost of maintenance.
LEDs last 100 times longer than incandescent lamps and use a fraction of the power to emit similar light intensity.
Another reason why the Coast Guard chose to convert incandescent lamps to LED bulbs while utilizing solar energy as a power source is an issue of reliability.
Captain Ed Enos has been bringing ships into port for nearly 20 years with the Hawaii Pilots Association and he is all too familiar with the importance of reliability in regard to navigation. His livelihood depends on it.
LED lights are far brighter, far more intense and far more visible, said Enos. Those are all good things that we as mariners want.
When an earthquake occurred on Big Island a few years ago it knocked out all power on Oahu including the inbound range light all mariners depend on for safe navigation into Honolulu Harbor. Enos was working with an inbound Horizon container ship that night when the lights went out.
“The entrance range is the most critical land aid,” Enos noted. “While the channel itself is lit by buoys, we don’t always rely on boating [navigation] aids. We visually key in on that lighted range and that night, due to power failure, we had no range. Nobody knew when we were going to get power back.”
After calling the Coast Guard Command Center, Enos was surprised to learn that there was no way of lighting the range with auxiliary power. “I think we all sort of assume there’s backup for everything and that’s not the case,” he continued.
As it happened, luck played a significant hand for Enos and his inbound container ship that night. “I was prepared to tell the captain of the ship that we’d have to wait a couple of hours, but the lights came on as I walked onto the bridge of the ship,” he said. “The situation resolved itself in that moment.”
Having dependable lighted aids is essential not only for the mariner but for island residents who rely heavily on commercial shipment of transported goods in the Hawaiian Islands.
Without calculable navigation aids, commercial ships would be unable to deliver essential supplies to the islands. “If we, as pilots, chose not to bring an inbound cargo ship from [the] mainland because of safety issues, that’s food and supplies for all Hawaii residents throughout the entire state,” said Enos. “Everybody is impacted by that. One small, little, seemingly trivial item in a grand transportation logistics scheme has a monumental impact on every single person living in this state.”
The Honolulu Harbor inbound range light has since been converted to LED, but that isn’t an option for some aids.
Reliability is just as important to the Coast Guard as it is to the mariners. For some navigation aids, the light needs to be so intense that it can be seen across vast distances. Because technology and industry haven’t developed lights that meet the full requirements for that light intensity, some navigational aids remain on commercial power until a viable alternative can be found.
As part of the decision to convert to LED, the Coast Guard determined that professional mariners prefer LED lighting over traditional lights when making night transits, said Cmdr. Peter Niles of the Visual Aids to Navigation Office at Coast Guard Headquarters in Washington, D.C. We are moving in the direction of making ranges lit with LED lights, but each range must be looked at individually to determine if LED lighting provides the best signal to the navigator. In some cases, it doesn’t.
The technology is evolving and the future is optimistic for LED lighting.
The Coast Guard continues its initiative to improve navigation aids just as ANT Honolulu works diligently to ensure the most efficient, reliable aids continue lighting the islands.