A Change in Store for Snow Fighters
Turners Falls Municipal Airport in Montague, Mass., has seen its winter patterns change in recent years and create challenges to keeping the airfield open.
Airport Manager Bryan Camden said only a few minor winter storms have hit the airport in the last couple of years. The only storm they got this season melted within a couple of hours of hitting the ground.
“Recently it has been more icing than snow,” he said. “A lot of these storms we have coming in are creating freezing rain and icing on the pavement versus snow. So far this year we’ve had more of that than actual snow events.”
The major issue for the Turners Falls Airport is ice packing and snow packing on the runway. Camden said snow drifting is common after New England storms, which creates this challenge.
“We try to plow in increments if we’re going to have a major snow storm,” he said. “That way we’re not doing all the heavy moving at once.”
At Sawyer International Airport in Gwinn, Mich., crews contented with heavy amounts of snow this past season. Duane DuRay, airport manager at Sawyer, said the area sees an average of 180 inches of snowfall during the winter season, but exceeded that amount before the end of February.
“There’s nothing average anymore,” he said. “Winters have changed drastically in the last few years.”
DuRay said part of the challenges lie in the FAA RCAM policies, which are difficult to meet in that region. The airport uses sand to increase friction for the surface condition, but RCAM doesn’t allow the use of sand to significantly increase the numbers.
They’re also using New Deal runway deicer, which he said has worked very well since its inception.
In late February, DuRay said Sawyer got hit with a massive snowstorm called a “cyclone bomb.” The region was hit with winds of up to 60 knots, coupled with a foot of snow and rain in the middle of the weather, to create about an eighth of an inch of ice.
“Rain in February is highly unusual and with the massive snow banks, there’s nowhere for it to go,” DuRay said.
“That has become the norm,” he said. “In previous years, we dealt with an average winter of 180 inches and that would be the high end, but the majority of it, dry snow.”
The Gunnison-Crested Butte Regional Airport in Gunnison, Colo., can see snowfall from October through May. Airport Manager Rick Lamport said the snow is typically wetter at the start and end of the season, but mostly dry snow during the course of the winter.
“From Dec. 1 to mid-March, our temperatures are well below sub-zero,” he said. “This year, we’ve had -30 degrees and during the daytimes, the temperatures might not go above seven or eight.”
The high altitude of Gunnison also creates challenges to combat ice. Lamport said despite the subzero temperatures, the infrared heat from the sun can cause melting and create ice issues on the runways and taxiways.
“Everything depends on pavement temperatures on how successful your runway performance is at the end of the day,” he said. “If your pavement temperatures are below zero and you get snow, then the snow is just going to fall on it and stay dry and it’s easy to remove.
“If your pavement temperatures are above freezing and you get snow and it melts, then it drops below freezing during the night, that’s when you start getting the freezing starting.”
The most challenging snowfall comes in the afternoons, Lamport said, because the asphalt on the airfield has been heated by the sun all morning, which means the surface temperature is above freezing despite the frigid ambient temperature.
“If it’s going to be an all-nighter, then we throw down anti-ice or deice material down because it keeps a blanket over it and then the next morning while it’s still subzero, you peel it up with steel bristle brooms rather than the poly steel brooms,” he said. “We found the poly polishes the ice, it doesn’t remove it, while all steel removes ice and tough ice.”
Mitigate Damage on the airfield
Brian Lawton, regional director of business development for Hi-Lite Airfield Services LLC, said glass beading inside markings can take a lot of damage during winter snow and ice removal operations. This can create issues with a new FAA circular issued at the end of 2018, which require remarkings to meet minimum reflectivity requirements outside of the initial installation of the paint.
Doing a reflectivity test before and after the winter can show a big decline in reflectivity of the markings, he said.
“Whether it’s brooming or plowing, it can do a lot of damage to the glass beads and therefore harm the reflectivity ,” Lawton said. “A lot of beads get dislodged with the brooming and the sweeping, the plowing, a lot of them get sheared off or break.”
Utilizing all steel brooms is effective on ice removal, but Lamport said it’s tough on markings and can create scour marks on the pavement. The airport has to paint or perform touchup work at least once per year.
“We paint as late as possible in the summer so the endurance of that paint is fresh from the onset of winter to at least the end of winter,” he said.
Camden said the new equipment ordered by Turners Falls includes a polypropylene edge as opposed to metal to minimize the impact on pavement and paint during snow removal operations.
Camden said the airport noticed metal edged plow blades can damage paint easier along with gouging in the asphalt.
“It’ll wear quicker, but you won’t have as much damage the asphalt surfaces,” he said about the rubber edges. “You won’t have paint chipping from it either.”
Gail Porritt, northeast representative for Asphalt Systems Inc., said age and load can cause stress to the aggregate on the airfield during snow removal.
“A healthy asphalt is going to be less susceptible to the damage than a less healthy asphalt pavement,” he said. “We would aggressively recommend preventive maintenance for all airfield pavements.”
Porritt said caster assemblies on the snow plows and brooms need to be adjusted so there’s not too much weight being put on them to the pavement. In an older pavement with more degradation of the binder, it needs to be adjusted to keep the aggregate in place.
“The thing we hate the most in the asphalt business are the steel bristle brooms,” he said. “We don’t mind the blades and the brooms sweeping off the top of the aggregate. What does the damage to the asphalt is when the broom gets down in where the binder is and scrapes that up, breaks the seal and makes it more porous and more susceptible to surface oxidation.”
Because of the high range of temperatures in Gunnison, Lamport said the airport has all asphalt surfaces on the airfield as it retains its heat better than concrete.
“Our commercial ramp is all concrete, but when it comes to snow removal, asphalt is far better in terms of mitigating that buildup of snow that occurs over the course of the day,” he said.
Gunnison is a Part 139 airport, so Lamport said they keep on top of regular inspections of the airfield in compliance with those standards. He said the state of Colorado is also very proactive in runway condition and pavement index assessments every few years.
“They come through and measure the cracks and they rate your pavements in terms of preventative maintenance requirements,” he said.
Steel blades and broom bristles can create more damage to the markings, so Lawton said it’s important for airports to consider alternatives, such as a combination of poly and steel bristles.
“The other thing to is operators really paying attention,” he said. “If you have a crew out there brooming and cleaning, and you’re laying idle in one position for a long period of time and you’re allowing the broom to be still moving when you’re sitting still on one marking, that will definitely be something that would hurt the marking.”
Lawton said the biggest step to prepare markings for winter is making sure they’re laid out correctly at installation.
“You’re using the correct materials, you’re calibrating your equipment, you’re preparing the surface and in your installation technique you’re putting the right amount of paint down and the right amount of beads down,” he said. “That’s really going to set you up the best to get those markings to last through winter.”
DuRay said mechanical methods of snow removal like brooms can damage pavement markings. Coupled with underbody plows with serrated and straight edges
“We have concrete taxiways and aprons, and an asphalt runway,” he said. “All of the surfaces are aggressively attacked with everything we have, so it’s hard on the surface.”
Sawyer will reassess its painted surfaces as spring progresses, DuRay said, to see what kinds of damage was incurred by the snow removal efforts during the harsh season.
“We schedule airfield painting once every three years, primarily because that’s when the FAA will allow us to paint with AIP funding,” he said. “Painting our surfaces can exceed $100,000 per event, so it’s not something that we can do randomly between winters.
“We’ll evaluate our surfaces to make sure they meet the FAA specs for coverage and reflectivity with the glass beads.”
DuRay said Sawyer will also reassess crack sealing as snow removal equipment can peel out tar sealers.
“We program this as well with our engineer and our annual project coordinating,” he said.
Porritt said after the winter season is over, you can go out and see the damage took place. Gouges and areas of cracked aggregate or scrapes are signs of damage. During the winter, you may also see asphalt binder appearing in brooms, meaning there may be issues with damage.
FAA Circular P-401 has a section that states any grinding on asphalt, the area needs to be treated with with a P-608 seal coat to tighten the area back up, Porritt said, and he recommends the same for areas damaged by plowing and sweeping.
“When you’ve got something like that, you need to reseal that pavement to tighten it back up, so there’s not environmental damage or surface oxidation” he said. “It will be less susceptible to that surface oxidation process when you seal those damaged areas back up.”
A standard emulsion needs to be at least 60 degrees to work properly. Porritt said P-608R is a solvent-based material and is more flexible to temperatures and can bind pavement earlier in the season.
“Our recommendation is the sooner the better,” he said. “The less you can expose that open area to water and UV, the better off you’re going to be.”
Asphalt-related FOD on the airfield during warmer seasons is a sign your surfaces may be susceptible to damage during winter snow removal. Porritt said checking the pavements for damage immediately in spring will give you an idea of what damaged occurred and binding efforts can take place in spring, summer and early fall, and it will be protected for winter.
“If you’re seeing that we’re going to recommend before winter comes, applying P-608 material to rebind that surface aggregate to tighten it up,” Porritt said. “That will protect it against the snow removal process.”
Get the right equipment in place
Jeremy Bernard, senior director of snow products for Oshkosh Airport Products, said climate is becoming more challenging on the micro level and becoming a lot more dynamic, which creates swings in temperature extremes. This can lead to the frequency and severity of weather events becoming much greater, particularly when it comes to snow events.
He said there’s also a major challenge with operator availability to tackle these events.
“What that means for us and what we think it means for the industry is ease of operation is becoming key for equipment and product development,” Bernard said. “We’re using very specific development processes and tools to generate intuitive vehicle layouts, intuitive cab layouts, intuitive vehicle controls and I’d even say intuitive vehicle operation.”
Bernard said Oshkosh developed an intuitive automatic locking transfer case, so operators don’t have to worry about switching the drivetrain on or off or locking and unlocking the transfer case. It also developed a system to automatically lift blowers when vehicles are placed in reverse as to not damage surfaces.
“It not only improves the operation of the vehicle, but it also improves the safety of the vehicle as well,” he said.
Bernard said ease of operation mitigates potential damage to airports by taking some of the unknown variables out of usage of snow removal equipment. He said technology allows the operations manager to set up the parameters in which a machine can be operated, lessening the chances of operation error.
“They’re able to set the parameters of the attachment, they can also set intervals in which it can be adjusted the frequency, he said. “With that ability, the vehicle goes out for its mission and is set up as to how it can operate. Having that control in place is key for not only optimizing operation, but for that interaction between the equipment and the attachment and the environment.”
DuRay said Sawyer primarily uses snow plows with underbodies and snow blowers. The airport is working to acquire a new 22-foot wide snow broom with a mixture of poly and steel bristles to combat compacted contaminants and whisk off other contaminants with the transition from freeze to thaw.
DuRay said the airport has also applied for AIP funding for a new snow plow. The plow will be 22-feet wide with an underbody, coupled with a combined sand and liquid spreader.
“Quite honestly, we’ve pulled out all the stops,” he said. “This is probably more common at some of the larger airports that have a larger SRE budget than we do.”
Camden said the airport purchased a Western Star 4900 Vocational Series truck with a 16-foot power angle snowplow. This was part of a grant awarded for snow removal equipment in April 2018.
He said the airport opted for the Western Star because of the durability of the truck and ability to customize the entire vehicle.
“We got to build ours from the frame up,” Camden said. “It’s not a cookie cutter, so everything we have coming with that truck is designed specifically for our needs: tighter turning radius, specialty tires, operator controls, everything about it we were able to customize to our specific needs.”
The airport also purchased a new 10-foot pusher box and 9-foot sweeping attachment, which Camden said will be used with a John Deere tractor.
Because of the Gunnison’s isolated location in the mountains and the difficulty of getting spare parts for equipment in the winter months, Lamport said the airport has invested in multiple pieces of the same equipment to ensure operations keep going in case of a breakdown.
Since he came to the airport, Gunnison has gone from one to three brooms; one to three plows; and Lamport said they currently have a second snow blower on order.
“Winter’s our busiest time. We get a lot of flights, wide body aircraft coming here in the winter,” he said. “Unfortunately, in the past, they had to shut the runway down because of low braking conditions.”
Bernard said to consider total cost of ownership when looking at new pieces of snow removal equipment. He said this includes a total fleet look as well as individual equipment and unit basis. Then the airport should have a primary focus on up time of the equipment, which includes part availability and serviceability.
“One thing that we’ve done using the technology and our resources is we’ve driven more than 80 percent commonality at a component level across all of our family of vehicles,” he said. “You have one radiator, one fan, one clutch for all broom trucks, plow trucks, blower trucks and also between the driving engine and the attachment engine. We also have drivetrain commonality across our entire fleet of airport products for our customers.”
He said airports should also focus on purpose built equipment for snow removal and focus on products built for the future.
“The technology trends are increasing and the rate of when technology is becoming available and being developed into the equipment is rapidly increasing,” Bernard said. “It’s key to look for equipment that has the appropriate base for the future. Things like telematics are coming, vehicle electrification is coming and other things are coming, so make sure your product has the right architecture for that.”
Bernard said airport managers should consider an operational assessment at the end of the winter season, so they can plan ahead and determine what they want the next winter season to look like when addressing snow removal.
“It’s absolutely critical that if a machines down, that they understand what it takes to replenish and repair that item to be ready for the next snow season,” he said.
