What does an increase in angle of attack primarily increase?

An increase in the angle of attack primarily increases induced drag. As the angle of attack increases, the aerodynamic lift generated by the wings also increases, up until the point of stall. However, as the angle of attack becomes greater, the airflow over the wings begins to separate, which increases the amount of induced drag. This phenomenon occurs because induced drag is directly related to the lift being produced; as lift increases due to a higher angle of attack, the induced drag also increases because the vortices formed at the wing tips become stronger and more pronounced.

In contrast, parasitic drag is associated with the shape, surface roughness, and other factors unrelated to lift or angle of attack. It remains relatively constant within a certain range of angles and is not significantly impacted by the angle of attack in the same way that induced drag is. Therefore, while both parasitic and induced drag contribute to the total drag acting on an aircraft, it is the induced drag that is significantly affected by changes in angle of attack.

Understanding this relationship is crucial for pilots, particularly when managing aircraft performance during maneuvers, as it affects flight efficiency, fuel consumption, and handling characteristics.