Why is frost considered hazardous to flight operations?

Frost is considered hazardous to flight operations primarily because it causes early airflow separation, which results in a loss of lift. When frost accumulates on the wings and other aerodynamic surfaces of an aircraft, it disrupts the smooth flow of air over these surfaces. This disruption occurs because frost alters the shape and smoothness of the wing's leading edges, causing the airflow to separate from the wing earlier than it would in ideal conditions.

The loss of lift is critical during flight, particularly during takeoff and landing phases, as it can lead to stalls and reduced control of the aircraft. Ensuring that the wings and control surfaces are free of frost is essential for maintaining the required aerodynamic properties for safe flight operations.

Other options highlight various concerns related to frost, but they do not directly address the primary and most dangerous effect that frost has on flight safety.