Private Pilot Private Exam

Why is frost considered hazardous to flight?

1. It increases the overall weight of the aircraft

2. It spoils the smooth flow of air over the wings

3. It causes the engine to malfunction

4. It obstructs the pilot's view

The correct answer is: It spoils the smooth flow of air over the wings

Frost is considered particularly hazardous to flight primarily because it disrupts the smooth flow of air over the wings, which is crucial for maintaining lift. When the wings have frost on their surface, they cannot produce the required lift efficiently since the irregular surface caused by frost alters the laminar flow of air. This can lead to a reduction in aerodynamic efficiency, making it more difficult for the aircraft to take off, climb, and maintain controlled flight. The presence of frost impacts the airflow patterns over the wing's shape, leading to increased drag and potentially causing an early stall due to insufficient lift. This is why proper de-icing procedures are essential before flying in conditions where frost is likely to accumulate on the aircraft's surfaces, particularly on the wings and control surfaces.