Managing Slippery Runways, Taxiways & Ramps At GA Airports
by Pete Vercouteren
Winter operations at general aviation (GA) airports can cause many challenges compared to the larger commercial airports. The challenges include availability of operations personnel, training, equipment, and budget. While many GA airports can simply shut down due to slippery runway conditions, those that accommodate corporate aircraft do not have that option.
Proper management of snow and ice at airports is essential for on-time winter operations. This is true for aircraft safety and the people moving within airside areas. Delays and employee injuries resulting from ineffective snow and ice control can cost airports and their customers precious time and revenues.
Equipment is the first consideration in controlling slippery conditions. Effective plows and especially mechanical brooms are essential to keeping surfaces clean and safe. Mechanical means also reduce the amount of chemical needed for control. Mechanical removal is typically preferred at low temperatures, below 15 degrees Fahrenheit, when snow is dry and does not bond to the surface.
When plows and brooms are not sufficient, chemical deicers must be used.
The use of chemical deicers is regulated by SAE AMS 1431 for solid materials and SAE AMS 1435 for liquids. To meet these certification standards, the deicers must pass airframe material compatibility, corrosion, storage stability, concrete, paint, and other standards. Further, suppliers must be able to supply proof of certification for their runway deicing products.
When deciding what chemical deicer(s) to use, one of the first considerations should be whether to be “proactive” (anti-icing) or “reactive” (de-icing). Liquid deicers are typically used as a “proactive” measure. They are applied before frost, ice, or snow accumulates. This technique requires less product to be used as it prevents frozen deposits from adhering to the surface and allows the remaining snow and ice to be removed easily with plows and brooms.
The first anti-icing application is made just before the event starts and again as needed during the storm (following mechanical removal to prevent bonding).
GA airports that I work with prefer to use Cryotech E36® Liquid Runway Deicer (LRD) as an anti-icer, because of ease of storage, ability to accurately apply the material, and cost. This clear liquid doesn’t settle, is very cost effective, and works at low temperatures. Its freezing point is -76 degrees Fahrenheit and throughout its temperature range, it flows like water.
Cryotech E36 LRD can take a lot of dilution before it refreezes. It can be stored in the spray equipment without causing corrosion.
Personnel or conditions may dictate that we use a “reactive” approach. Solid material is generally used in this approach. If there is a strong bond between the snow/ice pack and the surface, solid material will be more effective. Other important considerations in determining whether to use liquid or solid materials include pavement temperatures and current and forecast weather conditions. These conditions would include air temperature, winds, potential snow, sleet, or freezing rain.
Cryotech NAAC® Solid Runway Deicer (SRD) is preferred at the GA airports that I work with due to the application equipment or personal preference. NAAC is especially effective after a freezing rain or sleet event when there is ice bonded to the surface.
Sand and urea are two other commonly used solids. Sand may cause friction levels to improve in the short term; however, it has little long-term value in an on-going storm. There is also the concern of damage to propellers, brakes, and ingestion into airplane engines, as well as associated clean-up costs.
Urea has an effective working temperature of 28 degrees Fahrenheit, so it is not effective at cold temperatures. The Environmental Protection Agency (EPA) currently regulates urea due to its damaging environmental effect. When using urea, be sure to obtain the required certification papers.
Cryotech E36 and Cryotech NAAC meet the SAE AMS standards mentioned above. Their ability to work at low temperatures, and also their safety to aircraft, equipment, personnel, and the environment, make them the product of choice. These acetate deicers biodegrade and thus have little or no environmental impact.
Costs can be contained at GA airports by treating only 15 to 20 feet on either side of the centerline, and only in critical areas of the taxiways, such as turns and hold short areas. There is no need to treat the entire width of runways or taxiways, only the areas that would affect braking or steering control.
Costs can also be contained by the use of equipment that is already available, or can be easily and inexpensively converted. Most airports have dry spreading equipment. A grain drill is an innovative way that the Fond du Lac, Wisconsin airport is accurately applying NAAC. It is pulled by a pickup truck. Some GA airports are applying E36 LRD using a converted agricultural sprayer. The Sheboygan, Wisconsin airport uses a 300-gallon trailer sprayer that was designed for them. A sprayer installed in the back of a pickup truck works too, and this is the equipment used at the DeKalb, Illinois airport. All of these delivery methods have proven to be very effective.
The management of ice conditions can be made easy with the proper tools and training. To maintain safe operation areas and keep GA airports open during trying winter weather conditions, choose the proper equipment and chemicals. The cost does not have to be prohibitive.
EDITOR’S NOTE: Pete Vercouteren is president of V&Associates, Inc. in Fond du Lac, Wisconsin, representing Cryotech airport deicing products. He has a Master of Science Degree in Chemistry. His thesis dealt with deicers. A private pilot since 1984, Vercouteren has Instrument, and Single and Multi-Engine Land Ratings. V & Associates has been representing Cryotech for more than 25 years. For additional information call 920-923-4077 or 414-379-0601.