What is the primary reason for removing frost from the wings?

The primary reason for removing frost from the wings is that it degrades lift, adds drag, and increases stall speed. Frost can disrupt the smooth airflow over the wing's surface, which is critical for effective aerodynamic performance. When frost is present, it creates a rough surface that can significantly alter the wing's airflow characteristics, leading to a reduction in lift. This rough texture can also contribute to increased drag, which can further hinder the aircraft's performance during takeoff and flight.

Additionally, the presence of frost can raise the stall speed of the aircraft, meaning that the aircraft must reach a higher airspeed to maintain controlled flight. This increase in stall speed can be particularly dangerous during takeoff and landing phases, where flight safety is paramount. Therefore, removing frost is essential to ensure that the aircraft can perform safely and efficiently, maintaining the necessary aerodynamic properties for flight.

The other options don't address the fundamental aerodynamic issues caused by frost. Enhancing fuel efficiency and improving aesthetic appearance are secondary considerations, while maintaining weight distribution is not directly affected by frost. The critical factor remains the impact of frost on lift and drag, making its removal crucial for safe flight operations.