Which factor is not listed as influencing wingtip vortex strength in the material?

• A. Heavier weight
• B. Slower speed
• C. High angle of attack
• D. Flap configuration

Answer: (D)

Wingtip vortex strength tracks the amount of lift the wing must produce. The more lift required, the stronger the vortices shed from the wingtips. Heavier weight means the wing must generate more lift, so the vortices strengthen. Slower speed typically requires a higher lift coefficient to maintain level flight, so lift increases and the vortices become stronger. A higher angle of attack increases lift as well, leading to stronger vortices. In the material you’re studying, flap configuration isn’t listed as a factor affecting wingtip vortex strength, so it isn’t considered in that list. (Keep in mind that, in real aerodynamics, flap settings do influence lift and can affect vortex strength, but this question is about the factors given in that material.)