Wingtip vortices reach maximum strength during which flight phases?

• A. Takeoff, climb, and landing phases of flight
• B. Cruise
• C. Descent
• D. Approach

Answer: (A)

Wingtip vortices are created by the lift a wing generates. Their strength is tied to how much lift the wing is producing relative to the airplane’s speed. The lift is greatest when the aircraft is heavy and using a high lift configuration, with a higher angle of attack and often extended flaps—conditions that occur most during takeoff, the climb out, and landing. In these phases the wing is generating a lot of lift to get airborne, climb, and then settle onto the runway, so the vortices are strongest and persist longer.

During cruise, descent, or approach, the aircraft is typically flying faster with a lower lift coefficient, so the generated vortices are weaker and dissipate more quickly.