What is the primary consequence of icing on an airfoil?

The primary consequence of icing on an airfoil is that it increases stall speed. When ice accumulates on the wings and other surfaces of an aircraft, it disrupts the smooth airflow around the airfoil, leading to a significant change in aerodynamic properties. This disruption causes the airfoil to become less effective at generating lift, which means that a higher angle of attack is required to produce the same amount of lift. Consequently, as the aircraft approaches its critical angle of attack, the stall speed—the minimum speed required to maintain controlled flight—increases.

This increase in stall speed can lead to a greater risk of stalling, especially during critical phases of flight such as takeoff and landing, where maintaining adequate speed is essential for safety. Understanding the impact of icing is crucial for pilots as it directly influences their ability to fly safely and effectively. The other options do not accurately reflect the consequences of icing on an airfoil: improved lift is not achieved due to ice, drag typically increases rather than decreases, and icing does not lead to a shortened flight time.