When dicing or anti-icing equipment fails to reduce or control the icing hazard, how is the icing categorized?

When dicing or anti-icing equipment fails to reduce or control the icing hazard effectively, the icing is categorized as severe. This designation indicates a significant threat that not only poses a risk to flight safety but also typically requires immediate and serious attention by pilots and air traffic control. Severe icing conditions can lead to hazardous situations where aircraft performance is critically compromised, necessitating prompt action to avoid potentially dangerous outcomes.

In contrast, other categories such as light, moderate, or critical may describe varying levels of icing intensity, but they do not reflect the urgent implications posed when typical anti-icing methods are inadequate. In the aviation industry, accurate classification of icing severity is essential to ensuring safety during flight operations, and identifying conditions as severe allows for appropriate measures to be taken to safeguard the aircraft and its occupants.