What is the ground effect in aviation?

The ground effect in aviation refers to the increased performance of an aircraft when it is near the surface of the Earth, typically within the range of one wingspan from the ground. This phenomenon occurs because the presence of the ground affects the airflow around the wings, reducing induced drag and effectively increasing lift at lower speeds.

When an aircraft gets close to the ground, the air pressure differences that produce lift are utilized more efficiently, which allows the aircraft to achieve takeoff with less required speed and power. This plays a crucial role during takeoff and landing phases, where pilots can benefit from this improved lift-to-drag ratio, enabling smoother and safer operations close to the ground.

The other choices do not accurately reflect the nature of ground effect. Improved performance at high altitudes is the result of different aerodynamic principles, fuel consumption is influenced by various factors but is not directly tied to ground effect, and stall speeds are not inherently decreased due to ground effect when flying at high speeds.