Mixed ice is characterized by what feature?

Mixed ice is characterized by variation in drop sizes. In aviation weather phenomena, mixed ice occurs when supercooled liquid droplets collide with aircraft surfaces and freeze upon impact. This situation arises typically in cloud environments where there are both larger and smaller droplets present. The differences in droplet sizes lead to a mixture of ice types on the aircraft surfaces, which can affect the performance and handling characteristics of the aircraft.

Understanding this characteristic is crucial for pilots and air traffic controllers, as it helps them recognize potential icing conditions that may compromise safety. The presence of mixed ice indicates a complex interaction between the aircraft and the ambient weather conditions, necessitating careful monitoring and response.

The other choices do not accurately define mixed ice. Thickness pertains to the extent of ice accumulation but does not reflect the nature of the ice itself. A rough appearance relates more to the structural characteristics of the ice rather than its formation process. Instantaneous freezing would imply a rapid formation of ice, which is not a defining feature of mixed ice.