During takeoff, ground effect may cause which of the following?

• A. Reduced airspeed
• B. Increased airspeed
• C. Increased drag
• D. Decreased lift

Answer: (A)

When the wing is close to the ground, the airflow around it changes in a way that makes the wing work more efficiently. The ground blocks some of the wingtip vortices and reduces the downwash behind the wing, which lowers induced drag. Because the wing can produce the needed lift more easily at a lower angle of attack, the airplane can reach liftoff at a lower airspeed. So, during takeoff in ground effect, the airspeed required to become airborne is reduced.

The other ideas don’t fit this situation: you don’t need more speed because lift is not harder to generate in ground effect; drag from induction decreases rather than increases; and lift is not decreased—in fact, it’s enhanced at the same angle of attack.