FAA Ground School Practice Test

What is the definition of ground effect?

1. The increase in lift when flying at high altitudes

2. The result of the interference of the surface of the Earth with the airflow patterns about an airplane

3. The reduction of drag when flying in a jet stream

4. The turbulence created by an aircraft during takeoff

The correct answer is: The result of the interference of the surface of the Earth with the airflow patterns about an airplane

Ground effect refers to the phenomenon where the presence of the ground influences the airflow around an aircraft, particularly when it is close to the surface. When an aircraft flies at a low altitude, typically within one wingspan of the ground, the airflow patterns around the wings and the surrounding environment change. This interaction causes an increase in lift and a reduction in induced drag, which can enhance the aircraft's performance during takeoff and landing. The correct definition underscores how the proximity to the ground alters the airflow, creating additional lift that makes it easier for the aircraft to become airborne or maintain flight close to the surface. Understanding ground effect is crucial for pilots as it impacts their approach to landing and takeoff, allowing for safer and more efficient operations near the ground.