What happens to induced drag as the speed of the aircraft decreases?

As the speed of the aircraft decreases, induced drag actually increases. This is rooted in the principles of aerodynamics. Induced drag is a result of lift generation; as an aircraft generates lift, it disrupts airflow, creating vortices that result in drag.

At lower speeds, an aircraft must increase its angle of attack to maintain the required lift. This higher angle of attack leads to stronger vortices and, subsequently, increased induced drag. Conversely, at higher speeds, the aircraft can produce sufficient lift (due to both increased airspeed and more effective wing performance) with a lower angle of attack, which reduces the induced drag.

This understanding highlights the relationship between lift, angle of attack, and induced drag and explains why induced drag behaves the way it does with changes in speed.