What is a critical effect of structural icing on an aircraft?

Structural icing has a significant impact on an aircraft's performance, particularly in how it affects aerodynamic properties. When ice accumulates on the wings, tail, and other surfaces, it alters the shape and smoothness of those surfaces, which can lead to a loss of lift and changes in drag. This change in aerodynamic properties can result in reduced stability and control of the aircraft.

Understanding that icing changes the airflow around the aircraft is essential. As ice builds up, it can create rough surfaces that disrupt the laminar flow, a smooth airflow that is critical for maintaining lift. Moreover, the additional weight of the ice increases the overall mass that the aircraft has to lift, which can severely impact its performance during takeoff, cruising, and landing. As a result, the aircraft may behave differently than expected, which can make handling more difficult and increase the risk of an incident if not addressed promptly.

In contrast, improved stability during flight, increased fuel efficiency, and better control response are not likely outcomes of structural icing. These factors are critical for safe and efficient flight operations and are adversely affected by icing conditions instead.