What effects does icing have on aircraft performance?

Icing has a significant impact on aircraft performance primarily by adding weight and disrupting the airflow over the wings and control surfaces. When ice accumulates on an aircraft, it not only increases the overall weight but also alters the aerodynamic shapes that are crucial for generating lift. This change in shape can lead to a premature stall by disrupting smooth airflow, which is necessary for efficient lift generation.

The added weight from the ice requires the aircraft to produce more lift, which can lead to higher stall speeds. Additionally, the disturbances in airflow increase drag significantly, making it more challenging for the aircraft to maintain its speed and climb. The combined effects of increased weight and disrupted airflow can severely decrease performance, especially in critical phases of flight such as takeoff and landing.

In contrast, the other choices incorrectly present the effects of icing; icing does not enhance lift or reduce drag, does not help in preventing engine overheating, and most certainly impacts performance beyond just visibility issues. Thus, the understanding of icing's detrimental effects is crucial for safe flight operations.