Type IV Anti-Icing Fluid Subjected to Light Freezing Rain: Visual and Thermal Analysis

Deicing the aircraft using fluid, prior takeoff is mandatory; since a thin layer of ice or snow can compromise the safety. With the same idea, to use anti-icing fluid during a frozen precipitation to protect the aircraft is also essential. Commercialized anti-icing fluids all pass the process of qualification as described in the SAE documents. One of these documents specifies a set of tests that reproduce freezing precipitation to obtain endurance time and then the holdover timetables. The endurance time is determined by visual inspection: when 30% of the plate is covered with frozen contaminants. With the evolution of technology and the venue of new tools, it may simplify the process, and at least confirm the observations. This paper proposed a thermal and visual analysis of the behavior of a Type IV fluid subjected to light freezing rain. During the precipitation, the plate temperature is measured with thermocouples and recorded using a visual camera and an IR camera. The use the visual camera in conjunction with the IR camera allowed to understand how the water drops interacted with the fluid and also to confirm the presence of frozen contaminants. The use of IR camera can be useful for the industry; however experimentation needs to be done before.