Private Pilot License (PPL) Aerodynamics Practice Exam

What is the result of sinkage related to wingtip vortices from large aircraft?

1. The turbulence disperses evenly

2. The vortices dissipate immediately

3. The vortices sink below the generating aircraft

4. The vortices rise to upper altitudes

The correct answer is: The vortices sink below the generating aircraft

Sinkage related to wingtip vortices from large aircraft occurs because the airflow over the wing creates rotating vortices at the wingtips, which spiral downward into the wake of the aircraft. As these vortices are formed, they have a tendency to sink below the level of the generating aircraft. This phenomenon is a direct result of the air pressure differences created by the aircraft's wings during flight. Understanding how these vortices behave is crucial for smaller aircraft flying in the vicinity of larger ones, as these vortices can have a significant impact on safety and stability. The vortices do not dissipate immediately; rather, they can linger in the air for a while, making it important for pilots to be aware of the risk of encountering them. Furthermore, the behavior of these vortices is not characterized by even dispersion or rising to upper altitudes. Instead, they maintain a tendency to descend, which is critical for pilots when planning their flight paths and takeoff/landing procedures. Being aware of the specific nature of wingtip vortices can aid in preventing potential wake turbulence encounters, ensuring safer operations near larger aircraft.