Refer to figure.
Wingtip vortex development begins during the phase of flight when an aircraft generates lift. This typically occurs during takeoff, landing, and cruising phases. When an aircraft generates lift, high-pressure air beneath the wing flows around the wingtip to the lower-pressure area above the wing. This creates a swirling motion at the wingtips, known as wingtip vortices. These vortices are particularly pronounced during slow flight, high angles of attack, and when the wings are generating maximum lift, such as during takeoff and landing.