What is the effect on induced drag of mass and speed changes?

Induced drag is primarily generated by the generation of lift, which is a byproduct of an aircraft's wings interacting with the airflow. A key relationship is that induced drag is inversely proportional to the square of the airspeed and directly proportional to the weight of the aircraft.

As speed increases, the lift is generated more efficiently, requiring less angle of attack to maintain level flight, thereby reducing induced drag. At higher speeds, the aircraft experiences lower induced drag because the total lift can be achieved with a lesser amount of induced drag being produced due to the reduction in angle of attack.

When it comes to mass, decreasing the aircraft's weight reduces the amount of lift that must be produced for level flight. With less lift required, the angle of attack can also be decreased, which contributes to a further reduction in induced drag.

Thus, as speed increases and mass decreases, the combined effect is a notable decrease in induced drag, which aligns with the understanding that both higher speeds and lower mass lead to a more streamlined and efficient flow over the wings. This relationship is crucial for pilots in managing their aircraft's performance and fuel efficiency during flight.