Which condition increases the strength of wingtip vortices?

• A. Heavier and faster
• B. Heavier and slower
• C. Lighter and slower
• D. Lighter and faster

Answer: (B)

Wingtip vortices get stronger as the lift the wing must produce increases and as the flight condition requires a higher lift coefficient. Being heavier means more lift is needed, so the circulation around the wing increases, producing stronger vortices. Being slower forces a higher lift coefficient to support the same weight, which increases induced downwash and the strength of the trailing vortices. Put together, heavier and slower yields the strongest wingtip vortices. Lighter and faster reduce the needed lift and the induced effects, so the vortices are weaker. This aligns with the common aviation axiom: heavy, clean, and slow creates the strongest vortices.