Which type of structural icing is considered the most dangerous?

Clear icing is regarded as the most dangerous type of structural icing due to its characteristics and formation process. It occurs when supercooled water droplets freeze upon contact with an aircraft’s surface, creating a transparent layer of ice that closely adheres to the structure. This type of icing can form rapidly in severe icing conditions and can build up to significant thickness, significantly affecting the aerodynamic performance of an aircraft.

In particular, clear ice is heavy and can cause increased weight on the wings and control surfaces, altering the aircraft's center of gravity and overall handling. The smooth surface of clear ice makes it particularly hard to detect and can lead to reduced lift and increased drag, which may not become apparent until it is too late for effective recovery.

Additionally, the removal of clear ice usually requires the use of de-icing or anti-icing systems, which can consume time and resources, further complicating pilot response in critical situations. This combination of factors contributes to clear icing being viewed as exceptionally hazardous in aviation contexts.

Understanding the risks associated with different types of icing is crucial for pilots and aviation personnel, allowing them to make informed decisions about flight safety and manage the operational risks posed by icing conditions.