Instrument Rating Checkride Practice Test

What happens to an aircraft's drag when icing occurs?

1. It decreases

2. It increases

3. It remains constant

4. It fluctuates randomly

The correct answer is: It increases

When icing occurs on an aircraft, the drag typically increases. This increase in drag is primarily due to the impact of ice accumulation on the airfoil surfaces, which disrupts the smooth flow of air over the wings and other critical surfaces. As ice forms, it alters the aerodynamic shape of the wings, increasing the boundary layer thickness and generating more turbulent flow. This disruption leads to a higher drag coefficient. Consequently, pilots may notice a decline in performance, requiring more power to maintain altitude or a specific airspeed. It's also important to understand that while other options imply a reduction or stability in drag, they do not reflect the real aerodynamic changes caused by ice. Icing can lead to more significant lift loss as well; hence, managing drag becomes crucial for maintaining control of the aircraft in adverse weather conditions.