Induced drag increases when airspeed is:

Induced drag is a type of aerodynamic drag that occurs due to the generation of lift. It is particularly influenced by the angle of attack and the airspeed of the aircraft. As airspeed decreases, the angle of attack must increase to maintain the same lift. This increase in the angle of attack leads to a corresponding rise in induced drag.

When the aircraft is flying at a lower speed, the wings are operating at a higher angle of attack to sustain lift, which increases the formation of vortices at the wingtips. These vortices are what create induced drag. Therefore, as the airspeed decreases, the induced drag increases because the aircraft requires a larger angle of attack to compensate for the reduced airflow over the wings, thus producing more lift and more induced drag.

Understanding this relationship is critical for pilots, as managing airspeed during various phases of flight is essential for optimizing performance and efficiency.