Upwash is defined as which of the following?

• A. air flowing upward into the wing from the front
• B. air flowing downward toward the wing from above
• C. air flowing along the wing surface toward the tip
• D. air flowing away from the wing in a horizontal plane

Answer: (A)

Upwash is the vertical component of the oncoming air that flows upward into the wing as it approaches the leading edge. This upward deflection occurs as the wing meets the air, setting up the flow that eventually travels over the upper surface. Behind the wing, the air is deflected downward, which is called downwash. The other descriptions describe flow along the surface toward the wingtip or flow horizontally away from the wing, which do not capture the upward approach of air toward the leading edge.