Why is frost considered hazardous to flight?

Frost is considered hazardous to flight primarily because it disrupts the smooth airflow over the wings, which is essential for maintaining lift. When frost accumulates on the surfaces of the airfoil, it creates an irregular surface that leads to increased turbulence and a significant loss of lift. The presence of frost affects the wing's ability to generate the necessary aerodynamic forces needed for flight, making takeoff and landing especially dangerous, as the aircraft may be unable to achieve the required lift to safely operate.

Additionally, the adverse effects of frost on airflow result in reduced control of the aircraft, which can compromise maneuverability and response in critical flight phases. Unlike polished surfaces that promote smooth airflow, frost creates roughness that hinders performance. Thus, it is crucial for pilots to ensure that their aircraft is free of frost before flight to maintain safe operational capabilities.