← All explained questions · Aerodynamics and Principles of Flight
What is the primary aerodynamic effect of flying within about one wingspan of the ground?
Choices
✓ A reduction in induced dragcorrect
Ground effect reduces induced drag by interfering with wingtip vortices and downwash.
A large increase in parasite drag
Ground effect reduces induced drag; it does not raise parasite drag.
A loss of all lift
Lift is not lost in ground effect; the airplane can fly at a lower speed.
An increase in the critical angle of attack
Ground effect does not change the critical angle of attack.
Why
Ground effect is a reduction in induced drag near the surface, which can let the airplane lift off below normal flying speed.
FAA source: Airplane Flying Handbook FAA-H-8083-3browse the reference library →
Original study question written for this course — representative of FAA knowledge-test topics, not an actual current FAA exam question.