Which temperature range is associated with clear ice formation?

Clear ice formation typically occurs when supercooled water droplets come into contact with a surface that is at or below freezing temperatures. The temperature range most commonly associated with this phenomenon is between 0º to -10º Celsius. In this range, supercooled water can remain in its liquid state despite being below freezing. When these droplets strike an aircraft's surface, they freeze instantly, forming clear ice.

This type of ice is particularly hazardous because it is hard and transparent, making it difficult for pilots to detect and assess the ice accumulation visually. As temperatures drop further below -10º, the likelihood of ice formation tends to transition to mixed or rime ice due to changes in the properties of the water droplets and how they freeze upon contact. Understanding this temperature range is crucial for pilots to effectively manage icing hazards during flight.