What does ground effect refer to?

Ground effect refers to the phenomenon that occurs when an aircraft is flying close to the ground, typically within one wingspan of the surface. In this zone, the airflow around the aircraft is influenced by the presence of the ground, which alters the aerodynamic characteristics of the wings.

When an aircraft approaches the ground, the air pressure beneath the wings increases due to the limited space for airflow. This increase in pressure leads to a reduction of induced drag, allowing the aircraft to maintain lift more efficiently at lower speeds. Consequently, this means that during takeoff and landing, an aircraft experiences a higher level of lift and a lower amount of drag when in close proximity to the ground.

This effect can significantly reduce the amount of power needed for a takeoff and can also contribute to a smoother landing. Understanding ground effect is crucial for pilots to manage their approach and landing techniques effectively.