What type of icing results from the instantaneous freezing of small water droplets?

Rime ice occurs when small, supercooled water droplets freeze instantly upon striking a surface, typically leading to a frost-like appearance. This process primarily happens in conditions where the air is cold enough to keep the droplets in a supercooled state, and they freeze upon contact with an object, such as an aircraft wing. The ice crystals formed are typically opaque and have a white or milky appearance, distinguishing rime ice from other types of ice that may form under different atmospheric conditions.

While clear ice forms from larger supercooled droplets that spread and freeze slowly, structural ice can refer to any ice that impacts the structure of an object, and mixed ice includes characteristics of both clear and rime ice, rime specifically addresses the instantaneous freezing mechanism of small droplets, which is a key characteristic that defines it. Understanding these differences is essential for assessing icing conditions effectively and for the safety management of aircraft operations.