Wake turbulence
Wingtip vortices from heavy aircraft: where they drift and how to avoid them.
10 min read · Airport operations and procedures
After this lesson you can
- Explain how a wingtip vortex is generated and why it is strongest behind a heavy, slow, clean airplane.
- Predict how a vortex sinks and drifts once it nears the ground, including in a crosswind and a quartering tailwind.
- Apply the FAA vortex avoidance procedures for landing and departing behind a larger aircraft on the same, a parallel, or a crossing runway.
- Explain why a light quartering tailwind is the worst-case wake encounter scenario.
Every airplane that produces lift also produces wake turbulence: a pair of counter-rotating vortices trailing from the wingtips. Encountering the wake of a much larger airplane can impose a rolling moment beyond what a light airplane ailerons can counter, and the turbulence inside the vortex core can damage an airframe at close range.
None of this is visible. A pilot has to build a mental model of where the vortex sits and how it moves, because by the time it is felt, avoiding it is no longer a choice.
The rest of this lesson
- 1.How a vortex is generated
- 2.How a vortex behaves
- 3.Vortex strength en route
- 4.Avoidance on landing
- 5.Avoidance on departure and en route
These 5 sections, their figures, the checks along the way and the end-of-lesson quiz come with the PPL track. Paid once, yours for good.
Key terms
Try to recall each definition before turning the card.