What does the term “ground effect” signify in aviation?

The term “ground effect” in aviation refers to the aerodynamic phenomenon where an aircraft experiences increased lift and reduced drag when it is flying close to the surface. This occurs because the presence of the ground interferes with the airflow around the aircraft's wings. When an aircraft is within one wing span of the ground, the position causes the air pressure below the wings to increase, resulting in additional lift. At the same time, the interference with the downwash of the wings reduces induced drag, allowing the aircraft to achieve more efficient performance during takeoff and landing.

This phenomenon is particularly significant during the landing phase, as pilots often notice that the aircraft feels "floaty" or that it requires less power to maintain altitude when very close to the runway. Understanding ground effect is vital for pilots, as it influences how they manage their approach and landing techniques, especially in small aircraft. The other options, such as increased drag during takeoff, reduced noise during landing, and enhanced fuel efficiency during flight, do not accurately capture the specific nature of ground effect.