Definition
A form of structural icing that combines the characteristics of both rime and clear ice, formed when an aircraft flies through a cloud containing a mixture of small supercooled water droplets and larger ones, or supercooled droplets together with snow or ice particles. The result is a rough, opaque, and irregular accumulation that can build quickly and conform poorly to the airfoil shape.
Plain English
Ice that forms on the aircraft with a mix of features — partly milky and rough like rime ice, partly smooth and glassy like clear ice. It usually looks lumpy and uneven.
Context Anchor
Seen in weather and instrument flying discussions about in-flight icing, especially when describing the type of ice forming on wings, windshields, antennas, or other exposed aircraft surfaces.
Derivation
Mixed' derives from the Latin 'miscere' meaning to blend, describing the combination of clear and rime icing features from different droplet sizes.
Why Pilots Care
Mixed ice adds weight and drag faster than either clear or rime ice alone, quickly reducing lift and increasing stall speed.
Grounding Statement
Picture flying through a cold cloud where some moisture freezes into a smooth layer while other frozen material sticks on top as rough lumps.
Intuition Check
Mixed ice does not mean ice mixed with dirt or slush. In aviation, it means aircraft ice that combines the smooth qualities of clear ice with the rough qualities of rime ice.
Example Sentence 1
The pilot reported mixed ice between 6,000 and 8,000 feet and requested a climb to clearer air.
Example Sentence 2
The pilot diverted around the area after the briefing showed mixed ice potential at the planned cruising altitude.