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Behind-the-Scenes: Aircraft Deicing


When the outside temperatures drop, our winter ops procedures kick into gear. Thanks to the hard work of Ramp Employees and Pilots across the system, Southwest and AirTran ensure that our planes are free from any snow, frost, or ice prior to takeoff as part of our deicing/anti-icing program. Onboard the aircraft, you typically only see the billowing clouds of steam that result from the application of the heated deicing/anti-icing fluid, but spraying the aircraft is actually a very calculated process. We use two types of propylene glycol-based fluids to keep our aircraft clean and safe: Type I aircraft deicing/anti-icing fluid and Type IV anti-icing fluid.
  • Type I helps us remove snow, frost, and ice. It is heated to between 160 to 200 degrees Fahrenheit, which is why it causes so much steam when it’s sprayed into the frigid air. The heat that is transferred from the fluid onto the aluminum aircraft surfaces protects the surfaces for FAA-prescribed minimum amounts of time from freezing precipitation while the aircraft is on the ground. Type I can be identified by its orange/amber color.
  • Type IV allows us to protect our planes from anticipated ice, snow, or frost build-up. Type IV has gel-like properties that allow it to adhere well to the aircraft. When it’s applied to a plane that has already been cleaned by deicing, it will absorb and melt falling snow. During takeoff, the movement of the plane causes Type IV to liquefy and flow off, which leaves behind a completely clean surface. Type IV is green in color.
Throughout the winter season, our Frontline Employees withstand the elements to ensure that we keep our planes free of contamination and our Customers safe. To see a Deicing Crew in action, check out the above video!