When a computer screen started to dim in the tower at Bangor International Airport (BGR) in early 2017, staff discovered something in the airfield lighting system, which required some proactive measures.
Controllers were also having issues using the touch screen system to control airfield lighting, so BGR looked into the issue and found the Windows XP system controlling the airfield lighting was at the end of life for Microsoft support.
“It also left it vulnerable to viruses and malware,” said Amy Quam, assistant operations manager at BGR. “At that point, we realized we didn’t have probably much longer with the system in order to keep it operational, so we decided to upgrade the computer system.”
Quam said BGR upgraded the computers, monitors and radios used in the system. The upgrade was an easier fix than full replacement of the system. It cost $34,000 as opposed to about $500,000 to replace the entire system.
“We contacted the manufacturer and discussed it with them and we also have an engineering consultant who looked into it as well,” she said. “We realized at that point that we could get away with just doing the computer upgrades and then in the future in a little bit of time, we’re going to look at replacing the entire system.”
The biggest challenge for BGR during the upgrade was making sure the runway remained operational, Quam said. The upgrade took two days and was completed May 4.
“We did the work during daylight hours but we always have the potential for bad weather or fog to move in and at that point we’d need the airfield lighting,” she said. “So in order to combat that challenge, we had one of our electricians in the tower along with the installer and the other one was at the lighting vault so he had the ability to manually turn on the lighting if needed.
An upgrade to the airfield
Guthrie-Edmond Regional Airport (GOK) in Guthrie, Oklahoma, completed an upgrade to its runway lighting system in December.
Schellon Stanley, airport director at GOK, said the $343,060 project included upgrading runway lighting from incandescent to LED lights, replacing the airfield wind cone, replacing the rotating beacon on the airfield and adding exit taxiway signage adjacent to the runway.
The FAA provided 90 percent of the funding for the project, with the remaining 10 percent split between the cities of Edmond, Oklahoma and Guthrie.
The GOK runway has five taxiways off of the runway with blue lights indicating the exits prior to the light up signage.
“Before the project, the lights came one when they were cued up by the pilots,” Stanley said. “Now it’s really neat because they come on at dusk. They’re operated by a photocell and stay on low intensity all night long. When the pilots come in, they can keep them on low or dial up the intensity five to seven clicks.”
Stanley said the airport wanted to replace the old stake-mounted runway lights in favor of base-mounted LED fixtures to tackle maintenance issues.
“If we had a light go out and it wasn’t just a light bulb, we had to dig up this light fixture and figure out if it was the transformer and plug it in and unplug it,” she said. “And if we couldn’t find it there, then we had to call in an electrician and track it up and down the runway.
“Once you found it and it was just that light, it was easy and just a matter of manual labor, but we’d get to the point where we’d have a section of lighting out and we’d have to call someone in to do that.”
A couple of weeks before the 45 day project commenced, Stanley said the entire lighting system for the airfield went down. At that time, leaders opted to not fix the lights because it wasn’t prudent to spend thousands of dollars to make them operational for 10 to 15 days.
“Before this was happening, we spent quite a bit of money on repairing the lights,” she said. “The project would also replace all the direct-bury circuit with a new power circuit in conduit. And we also replaced the wind cone with an LED fixture.”
Stanley said the project came in three days ahead of schedule despite a couple of weather days and challenges with the project.
Workers on the project stuck a large gas line during one phase of construction and on another day, a pilot came in with no engine while trucks were parked on the runway as it was closed at the time. No one was hurt in the incident.
Stanley said the biggest challenge during the project was keeping the runway open as long as possible during three phases of work. The airport kept 3,000 feet of runway operational during each phase of the project. When the middle section of the runway was under construction, workers did partial closures of the runway using chevrons and temporary thresholds.
“The two phases where this concept was used allowed the contractor a safe and efficient work area inside those safety areas,” Stanley said. “While at the same time, we were able to maintain a usable runway length of at least 3,000 feet.
“Using this method, the runway was only completely closed 10 days of the 45 working day project.”
Tupelo Regional Airport (TUP) in Tupelo, Mississippi has undertaken airfield lighting replacement after the old units with maintenance issues made it more cost effective to replace the units.
Cliff Nash, executive director, for TUP, said replacing the lights also played into a proposal to move to LED lighting and upgrade the taxiway lighting.
“The bulk of our lights are direct buried on stakes,” he said. “One of the things we’re trying to do is get everything into conduit and cans to help with servicing and maintaining the lights later.”
Nash said one taxiway at TUP and the southeast corner of the commercial apron have LED lighting. They were placed on the apron as a test to see how they performed in operation.
The Peru Municipal Airport in Peru, Indiana, is in a multiphase project to upgrade its airfield electrical system, which includes the installation of LED lighting.
Mark McIver, president of the Peru Board of Aviation, said upgrades began in 2013 with the replacement of the electrical vault.
“It was quite antiquated,” he said. “I believe it was constructed around 1986.”
McIver said the airport put a precast structure in with lightening arrest equipment to protect the sensitive systems.
The airport planned the next phase for the current fiscal year, which McIver said includes duct banks, a rotating beacon, guidance signs and LED equipment.
Peru has issues with older wires, insulation issues, grounding issues and safety concerns with the electrical system breaking down.
“Our final phase will be basically completed in 2020, which will consist of replacement of the runway edge lighting and markers of the perimeter of the runway pavement,” McIver said. “Basically, our challenge with this project has been limited funding and keeping our lights on and the cost of electricity lower.”
McIver said the airport worked with NGC Corp. on its electrical costs. As they continue to rise, the airport keeps looking for more efficient equipment to keep costs down.
“We wanted to reduce electrical costs and do that through better technology involved with the LED and also make it safer,” he said. “NGC Corp. is designing lightening arrestors at multiple locations in case of electrical strikes. That will mean less replacements and longer lifetime bulbs with the LED.”
Changing approach with LEDs
Corey Stutz, marketing manager, for the Americas for ADB Safegate, said the switch from incandescent lights to LED lights on the airfield creates new challenges for airports when it comes to putting together a regular maintenance plan.
Old lights would last about 500 hours, so almost every quarter airport maintenance staff would be replacing a bulb in a fixture. When LED lights are put into the airfield, the bulb replacement goes down, so other maintenance procedures like torqueing might get overlooked because staff performed them while replacing bulbs.
“I’m talking about cleaning out the prism windows. I’m talking about doing photometric assessments, it’s the torqueing of the light fixtures,” Stutz said. “As your airport lighting fixture sits in the field, they’re getting hit by aircraft, especially in certain areas of touchdown zones GDC, centerline lights.”
Runway light torqueing became a major issue after a high profile case in 2014 where a Delta Air Lines 747 was impaled by a loose light while taking off from John F. Kennedy International Airport (JFK).
Stutz said it’s important for airports to put a program in place to make sure staffs are validating the torque on a regular basis and making sure it meets the requirements set forth by the Federal Aviation Administration (FAA).
Airfield lights can also take damage from the elements and during runway maintenance, which can create some issues with the quality of the light being produced.
“I can’t let a light sit in the field for seven years and not really know what the degradation is of the light output,” Stutz said. “It’s stuff on the prism, it’s muck caking on the light window because some of these fixtures have negative slope, so you have water and debris and dirt going into the prism and then you get this film on the light prism.”
Stutz said airports can use photometric airfield testing equipment on a regular basis to check the quality of the light output from each unit. The equipment can be pulled down a runway and light output measures from each unit and compared to FAA standards.
“Ground airfield lighting maintenance has evolved from replacing a light to now I have to do much more different things that are requiring a little more technology,” he said.
Stutz said airports can also consider an asset management system for tracking airfield lighting repairs. After workers perform maintenance and torqueing on a light fixture, the job is logged and sent to a database. The information allows staff to look at trending data and verify assets are being inspected on a regular basis and placed in spec with their manufacturer recommendations.
“It’s about knowing what’s out there and making sure the tool is as simple as possible to use and it’s not adding a huge workload to my already strapped maintenance team,” Stutz said.
Keeping all of the torqueing information in one database helps with FAA Part 139 inspections, Stutz said, because it provides all the information the agency requires from airports.
“Torqueing of light fixtures is not an easy, simple task, especially if they are having to do it every three months or so,” Stutz said.
Photometric calibration equipment
Preparing for maintenance with an LED lighting field requires education about the regulations before getting equipment, Stutz said. Once an airport learns what will be expected of it to maintain its airfield lighting systems, it helps leaders determine the type of equipment it needs to meet the standards.
Utilizing the equipment also requires staff to learn how to use it even though some might only touch it a couple of times per year, Stutz said. Companies like ADB Safegate do offer the testing as a service and will send teams to work with airport maintenance officials to perform the inspections so the airport doesn’t need to provide highly specialized training to a handful of workers.
“It’s not something that if you aren’t experienced with doing it then you almost have to have someone whose gone to specialized training or you have to hire someone as a service level agreement to do that for you.
“The next part is you’re asking me then to learn a new tool; something I don’t have experience with and for something like the photometric one that I may only touch twice a year. Now I have to have a team that does photometric testing of airfield lighting, so is it a purchase decision or do I do it as a service,” Stutz said. “